z/OS Communications ServerVersion 2 Release 3

SNA Network Implementation Guide

IBM

SC27-3672-30

Note:

Before using this information and the product it supports, be sure to read the general information under“Notices” on page 643.

This edition applies to Version 2 Release 3 of z/OS® (5650-ZOS), and to subsequent releases and modifications untilotherwise indicated in new editions.

Last updated: 2019-07-03© Copyright International Business Machines Corporation 2000, 2019.US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract withIBM Corp.

Contents

Figures................................................................................................................ xv

Tables...............................................................................................................xxiii

About this document........................................................................................ xxviiWho should read this document.............................................................................................................xxviiHow this document is organized............................................................................................................ xxviiHow to use this document..................................................................................................................... xxviii

How to contact IBM service............................................................................................................. xxviiiConventions and terminology that are used in this information.......................................................... xxviiiHow to read a syntax diagram................................................................................................................. xxixPrerequisite and related information...................................................................................................... xxxi

Summary of changes for SNA Network Implementation Guide......................... xxxviiChanges made in z/OS Communications Server Version 2 Release 3.................................................xxxviiChanges made in z/OS Communications Server Version 2 Release 2, as updated June 2017.........xxxviiiChanges made in z/OS Version 2 Release 2, as updated September 2016.......................................xxxviiiChanges made in z/OS Version 2 Release 2, as updated March 2016...............................................xxxviiiChanges made in z/OS Version 2 Release 2..........................................................................................xxxixChanges made in z/OS Version 2 Release 1, as updated September 2014.........................................xxxixz/OS Version 2 Release 1 summary of changes....................................................................................xxxix

Chapter 1. Post-installation considerations for z/OS Communications Server.......... 1Defining Communications Server SNA to z/OS........................................................................................... 1Using automatic restart manager................................................................................................................ 1Starting z/OS Communications Server SNA................................................................................................ 2

Chapter 2. VTAM networking concepts................................................................... 5VTAM functions............................................................................................................................................ 5VTAM nodes..................................................................................................................................................5

Nodes with APPN function only............................................................................................................. 5Nodes with subarea function only..........................................................................................................8Nodes with both subarea and APPN function........................................................................................9

Network accessible units...........................................................................................................................11Physical unit......................................................................................................................................... 11Logical unit............................................................................................................................................11

Network control sessions.......................................................................................................................... 12SSCP-SSCP sessions............................................................................................................................ 12CP-CP sessions.....................................................................................................................................12

User sessions............................................................................................................................................. 13How VTAM locates resources.................................................................................................................... 14

Locating resources in a subarea network............................................................................................ 14Locating resources in an APPN network..............................................................................................15

Route selection.......................................................................................................................................... 15Routing in a subarea network.............................................................................................................. 15Routing in an APPN network................................................................................................................ 16

Addressing................................................................................................................................................. 18Subarea addressing..............................................................................................................................18APPN addressing.................................................................................................................................. 18

iii

Controlling network data flow using pacing..............................................................................................18Pacing concepts................................................................................................................................... 19Pacing window......................................................................................................................................19

Chapter 3. Implementing a VTAM network............................................................21Using start options and configuration lists................................................................................................22

Start options......................................................................................................................................... 23Configuration lists.................................................................................................................................30

Identifying resources to VTAM.................................................................................................................. 31Coding concepts................................................................................................................................... 31Sift-down effect....................................................................................................................................32Using MVS system symbols..................................................................................................................32

Verifying a VTAM network..........................................................................................................................38Verifying a multiple-domain subarea network.................................................................................... 39Verifying a multiple-network environment..........................................................................................39Verifying a VTAM APPN network.......................................................................................................... 39

Chapter 4. Connecting an APPN node to VTAM......................................................41Connections through boundary function-based transmission groups.....................................................41Multiple connections with parallel transmission groups.......................................................................... 42Channel connections between APPN nodes.............................................................................................42

Multipath channel connections............................................................................................................42Composite network node channel connections.................................................................................. 49

Leased connections between APPN nodes...............................................................................................50IBM 3172 Nways Interconnect Controller connections between APPN nodes...................................... 51

Examples.............................................................................................................................................. 51Using a connection network.................................................................................................................52IBM Open Systems Adapter connections between APPN nodes....................................................... 57

APPN multiple network connectivity.........................................................................................................78Peripheral subnetwork boundaries......................................................................................................80Extended subnetwork boundaries.......................................................................................................80APPN multiple network connectivity support..................................................................................... 80

Virtual-route-based transmission groups.................................................................................................83Defining a VR-based TG........................................................................................................................85VR-based TG recommendations.......................................................................................................... 86

Selecting the network node server for end nodes.................................................................................... 88Creating a network node server list..................................................................................................... 88Activating, replacing, and displaying a network node server list........................................................89Using the NNSPREF start option..........................................................................................................89

Chapter 5. Connecting a subarea node to VTAM.................................................... 91Connecting two VTAMs using channels.....................................................................................................91

Channel-to-channel adapter connection.............................................................................................91Multipath channel connections............................................................................................................93

Connecting two VTAMs using an external communication adapter......................................................... 93Sample configuration with Ethernet or Ethernet-type LAN................................................................ 94Sample configuration with a token-ring local area network............................................................... 95

Chapter 6. Using Enterprise Extender (EE)............................................................ 99Overview.................................................................................................................................................. 100

Benefits of Enterprise Extender.........................................................................................................100Availability of Enterprise Extender.................................................................................................... 100Hardware requirements.....................................................................................................................100EE reliability and strategy.................................................................................................................. 101Using EE and extended border node (EBN) as a replacement for SNI............................................. 102EE implementation considerations....................................................................................................102

Designing the EE network........................................................................................................................103

iv

Distinctions between an EE network and an EE connection network.............................................. 103Characteristics of EE connections..................................................................................................... 103Static VIPA considerations.................................................................................................................104IP multipath considerations ..............................................................................................................105Class of Service preservation dependencies.....................................................................................105Comparing host name and IP address definitions............................................................................ 106

Configuring the EE network..................................................................................................................... 107Preservation of SNA transmission priority........................................................................................ 109Network address translation (NAT) considerations ......................................................................... 109Steps for configuring and activating an EE network..........................................................................109

Configuring the EE connection network..................................................................................................124Connection network concepts........................................................................................................... 129EE connection network rules............................................................................................................. 130Contrasting local and global networks.............................................................................................. 130Benefits of defining multiple Enterprise Extender virtual routing nodes......................................... 130Defining an EE connection network in the EE XCA major node ....................................................... 133

EE security considerations...................................................................................................................... 135SNA session level encryption (SLE) .................................................................................................. 135IP security (IPSec)............................................................................................................................. 135Using EE with network address translation (NAT)............................................................................ 136IP filtering...........................................................................................................................................137IDS for Enterprise Extender...............................................................................................................137OEM security products - EE proxy solutions..................................................................................... 138

Tuning the EE network.............................................................................................................................138Tuning Enterprise Extender-specific buffer pools ............................................................................138Timers.................................................................................................................................................139HPR ALIVE timer optimization for Enterprise Extender....................................................................142Enterprise Extender LDLC keep-alive reduction............................................................................... 142Enterprise Extender improved packet loss tolerance.......................................................................143Disconnect and inactivity summary...................................................................................................143Customizing IP type of service.......................................................................................................... 144

Advanced coding considerations for EE..................................................................................................145EE connection network reachability awareness ...............................................................................145TCP/IP MTU size for EE ..................................................................................................................... 152Running EE in constrained or virtualized environments................................................................... 153RTP transmission stall operator awareness and recovery support.................................................. 154Load balancing................................................................................................................................... 155Transmission group profiles...............................................................................................................155Dynamic reconfiguration....................................................................................................................156Dial usability - DWACT, DWINOP, KEEPACT, REDIAL, and REDDELAY............................................. 156Customization for EE connection network PUs................................................................................. 157Cross-subnet routing with global VRNs.............................................................................................158

Troubleshooting EE problems................................................................................................................. 160

Chapter 7. OSA-Express.....................................................................................167OSA-Express overview............................................................................................................................ 167Defining an OSA-Express device to z/OS Communications Server using QDIO.................................... 169OSA routing.............................................................................................................................................. 171

OSA-Express virtual MAC (VMAC) routing ........................................................................................ 171Primary and secondary routing..........................................................................................................173

Outbound priorities..................................................................................................................................174MTU.......................................................................................................................................................... 175

Chapter 8. Defining resources dynamically......................................................... 177Defining switched resources dynamically...............................................................................................177

Dynamic PU definition (DYNPU operand).......................................................................................... 177Dynamic switched definitions............................................................................................................177

v

Dynamic configuration of channel-attached devices............................................................................. 180Installation and preparation.............................................................................................................. 181Defining your configuration................................................................................................................182Building resource definitions............................................................................................................. 182Using the default naming convention................................................................................................ 183Customizing the command lists.........................................................................................................183

Dynamic reconfiguration and change of operands................................................................................. 184Dynamic reconfiguration and dynamic change requirements.......................................................... 185Using the VARY ACT,UPDATE technique............................................................................................186Using the VARY DRDS technique....................................................................................................... 188Using the MODIFY DR technique....................................................................................................... 190Dynamic reconfiguration of independent LUs................................................................................... 190

Chapter 9. Defining peripheral nodes................................................................. 193Defining type 2.1 peripheral nodes.........................................................................................................193

Nonnative network type 2.1 connections..........................................................................................194Attaching peripheral nodes to VTAM.......................................................................................................195

Local non-SNA connection.................................................................................................................195Local SNA connection........................................................................................................................ 196Loop-adapter-attached connection...................................................................................................197External communication adapter (XCA) connections....................................................................... 197

Chapter 10. Defining LUs....................................................................................201Independent LUs..................................................................................................................................... 201

Characteristics of independent LUs...................................................................................................201Defining independent LUs..................................................................................................................202Multiple connections between a type 2.1 node and a subarea node...............................................206Dynamic selection of session connections........................................................................................207Authorized transmission priority for LEN connections..................................................................... 208Restrictions on using independent LUs............................................................................................. 208Dependent logical units..................................................................................................................... 208

Chapter 11. Establishing and controlling SNA sessions....................................... 211Multicultural support............................................................................................................................... 211

Multicultural support for user USS messages and commands.........................................................212Defining USS tables for use with the LANGTAB operand ................................................................. 212Defining USS messages to the MVS message service.......................................................................212Multicultural support for the language passed to application programs......................................... 213

Model name table.................................................................................................................................... 213Associated LU table................................................................................................................................. 214Selecting session parameters for the logon mode table........................................................................215Automatic logons.....................................................................................................................................221

Coding for automatic logon................................................................................................................222Operator commands for automatic logon......................................................................................... 224Reallocation of autologon sessions................................................................................................... 224

Session management exits......................................................................................................................227Session authorization.........................................................................................................................228Session accounting............................................................................................................................ 229

Session-level pacing................................................................................................................................229Fixed session-level pacing.................................................................................................................230Adaptive session-level pacing........................................................................................................... 230Setting initial pacing values............................................................................................................... 231Sample configurations....................................................................................................................... 236

Logon and logoff requests from dependent logical units....................................................................... 245Unformatted logon requests using mixed-case passwords...................................................................245

Chapter 12. Network routing..............................................................................247

vi

Network routing and resource location for APPN nodes........................................................................247Types of searches...............................................................................................................................248Minimizing broadcast searches......................................................................................................... 250Network search overhead caused by duplicate resource definitions...............................................253Avoiding congestion........................................................................................................................... 253Checkpointing of the TRS database and the directory database..................................................... 254APPN Class of Service........................................................................................................................ 254APPN network routing through a composite network node (CNN)...................................................262Using the SAMAP table...................................................................................................................... 265

Network routing for subarea nodes........................................................................................................ 268Physical paths.................................................................................................................................... 269Logical paths...................................................................................................................................... 271How session traffic is assigned to a specific route............................................................................272How to plan routes in your network...................................................................................................276How VTAM handles network and subarea addressing......................................................................279Virtual route pacing............................................................................................................................282Parallel sessions using parallel transmission groups....................................................................... 285Dynamic path update......................................................................................................................... 286

Chapter 13. Application programs...................................................................... 289Naming an application program.............................................................................................................. 289Model application program definitions................................................................................................... 290

Overview.............................................................................................................................................290Coding guidelines...............................................................................................................................291How VTAM finds the best match........................................................................................................293Example of using model application program definitions................................................................ 294Resource state requirements............................................................................................................ 295

Authorizing application facilities.............................................................................................................295Passing and validating logon requests.............................................................................................. 295Overriding dial number digits for dial or token-ring connections..................................................... 295Acquiring LU sessions........................................................................................................................ 296Enabling parallel sessions................................................................................................................. 296Authorizing privileged paths.............................................................................................................. 296

Data compression....................................................................................................................................296Types of compression........................................................................................................................ 296Implementing data compression...................................................................................................... 297Compression level negotiation.......................................................................................................... 298Summary of data compression..........................................................................................................300

Security features......................................................................................................................................300Cryptography facility.......................................................................................................................... 301Message authentication.....................................................................................................................309SLU authentication............................................................................................................................. 310VTAM application security................................................................................................................. 310Confidential data................................................................................................................................ 3103270 Intrusion Detection Services....................................................................................................311

Logon mode parameters......................................................................................................................... 330Using user variables (USERVAR)............................................................................................................. 331

Application workload balancing with USERVAR................................................................................331Classes of USERVARs.........................................................................................................................331Types of USERVARs............................................................................................................................332Processing USERVARs........................................................................................................................333USERVAR propagation and routing....................................................................................................334Defining your network with USERVARs............................................................................................. 335Dynamic USERVAR update session failure........................................................................................335

Generic resources function..................................................................................................................... 336High availability using extended recovery facility...................................................................................337

Security features in an XRF environment.......................................................................................... 337

vii

LU 6.2 in an XRF Environment........................................................................................................... 338Persistent LU-LU sessions....................................................................................................................... 338Single node persistent sessions..............................................................................................................339VTAM common network services............................................................................................................ 341Cross-memory application programming interface (API)...................................................................... 341Allocating private storage........................................................................................................................341Communicating with start-stop devices................................................................................................. 342LU 6.2 application programs................................................................................................................... 342

Enabling LU 6.2 support.....................................................................................................................342LU 6.2 sessions...................................................................................................................................342LU 6.2 session limits.......................................................................................................................... 344Managing LU 6.2 sessions with operator commands........................................................................345LU 6.2 security....................................................................................................................................346LU 6.2 sync point services................................................................................................................. 347Selective termination of idle LU 6.2 sessions....................................................................................347Selective termination of idle network management sessions..........................................................348APING support................................................................................................................................... 349High-performance data transfer (HPDT)........................................................................................... 351

Communications storage manager (CSM)...............................................................................................352

Chapter 14. CMIP application programs............................................................. 353VTAM topology agent CMIP application program...................................................................................353Implementing CMIP services.................................................................................................................. 353What the topology agent does................................................................................................................ 354How data flows between the topology manager and the topology agent............................................. 355Associations and using the directory definition file for CMIP services.................................................. 355

Controlling associations.....................................................................................................................355Determining security for associations............................................................................................... 356Updating the directory definition file.................................................................................................357

Chapter 15. Functions provided by VTAM in a sysplex......................................... 359Setting up the sysplex environment for VTAM and TCP/IP functions.................................................... 359

Sysplex subplexing.............................................................................................................................359Considerations................................................................................................................................... 361Coupling facility structure attributes.................................................................................................362Determining the size of the coupling facility structure..................................................................... 364Sample CFRM coding......................................................................................................................... 364Connecting to and allocating storage for coupling facility structures.............................................. 366Structure rebuild................................................................................................................................ 366Coupling facility duplexing.................................................................................................................367Coupling facility storage shortages................................................................................................... 367Dynamic altering of structures...........................................................................................................367

Dynamic definition of VTAM-to-VTAM connections................................................................................368Generic resources....................................................................................................................................370

Generic resources requirements....................................................................................................... 370Generic resource mapping.................................................................................................................371Partner LU mapping............................................................................................................................372Initiating sessions with generic resource members......................................................................... 375Implementation considerations........................................................................................................ 376Coupling facility failures for generic resource configuration............................................................ 377Removing a generic resource.............................................................................................................378Routine maintenance for VTAM nodes.............................................................................................. 383

Multinode persistent sessions................................................................................................................ 384Multinode persistent session configuration requirements............................................................... 386Using multiple coupling facility structures for multinode persistent sessions................................ 387Establishing multinode persistent sessions......................................................................................388Coupling facility failures for multinode persistent session configuration........................................ 391

viii

Failure recovery processing............................................................................................................... 392MNPS planned and forced takeover processing............................................................................... 394What to do if recovery does not occur or complete.......................................................................... 397

TSO generic resources.............................................................................................................................398Sysplex-wide security associations........................................................................................................ 399

Coupling facility failures for sysplex-wide security associations..................................................... 399Failure of a TCP/IP stack.................................................................................................................... 399Failure of a VTAM node...................................................................................................................... 399Rebuild of the sysplex-wide security associations structure (EZBDVIPA)....................................... 399Disconnect from the EZBDVIPA structure.........................................................................................400Modifying the number of lists............................................................................................................ 400

Sysplexports............................................................................................................................................ 401Coupling facility failures for Sysplexports.........................................................................................401Failure of a TCP/IP stack.................................................................................................................... 401Failure of a VTAM node...................................................................................................................... 401Rebuild of the Sysplexports structure (EZBEPORT)..........................................................................401Disconnect from the EZBEPORT structure........................................................................................ 402

Chapter 16. Implementing an APPN network......................................................403Coding considerations for APPN resources............................................................................................ 403Maximum APPN Locate size considerations...........................................................................................405Enabling control sessions........................................................................................................................405

CP-CP sessions between two VTAM nodes....................................................................................... 405Defining adjacent APPN nodes.......................................................................................................... 405Defining the logon mode for CP-CP sessions.................................................................................... 406

High-Performance Routing (HPR)........................................................................................................... 406What is High-Performance Routing?..................................................................................................406What is Rapid Transport Protocol?.................................................................................................... 407What is automatic network routing?..................................................................................................408How does HPR switch paths?............................................................................................................ 409HPR implementation overview.......................................................................................................... 409Setting session paths using HPRNCPBF............................................................................................417

Chapter 17. Implementing a combined APPN and subarea network.................... 419Start options defining a combined subarea and APPN environment..................................................... 422

SORDER start option.......................................................................................................................... 422SSEARCH start option........................................................................................................................ 422CDRSCTI start option......................................................................................................................... 422IOPURGE start option........................................................................................................................ 423

Dependent LUs........................................................................................................................................ 423Dependent LU server..........................................................................................................................423Dependent LU server support across subnetwork boundaries........................................................ 426

Defining CDRSCs......................................................................................................................................428SSCP takeover..........................................................................................................................................428Establishing and controlling sessions..................................................................................................... 431Controlling searches................................................................................................................................431

Using SORDER to control network search order............................................................................... 431Using SSEARCH to limit subarea network searches......................................................................... 432Using the CDRSCTI start option to reduce broadcast searches of APPN.........................................432Using the DISJOINT operand to define disjoint subarea networks..................................................432

APPN and subarea Class of Service resolution.......................................................................................434Resolving logon mode names to subarea and APPN Classes of Service..........................................435Defining APPN and subarea Classes of Service in logon mode tables............................................. 437Defining APPNTOSA and SATOAPPN class of service mapping tables.............................................438

Adding and moving nodes....................................................................................................................... 438

Chapter 18. Implementing a subarea network.................................................... 439

ix

Start options defining other domains......................................................................................................440Defining the location of cross-domain resource managers by coding adjacent SSCP tables..........440Defining the location of cross-domain resource managers dynamically......................................... 441Specifying timeout values for locating cross-domain resources......................................................441

Identifying VTAMs in other domains (CDRMs)........................................................................................441Identifying resources in other domains.................................................................................................. 443

Dynamic definition of cross-domain resources.................................................................................443Static definition of cross-domain resources..................................................................................... 445Model definition of cross-domain resources.....................................................................................446Adjacent SSCPs.................................................................................................................................. 449CDRM owner verification for cross-domain resources......................................................................455Changing ownership of cross-domain resources.............................................................................. 456Shadow resources..............................................................................................................................456

Chapter 19. Connecting multiple subarea networks............................................ 457Defining a multiple-network environment..............................................................................................457SNI configurations................................................................................................................................... 459Start options defining other networks.................................................................................................... 460

Start options for gateway VTAMs.......................................................................................................460GWSSCP start option for nongateway VTAMs................................................................................... 460Configuration lists for gateway VTAMs.............................................................................................. 461

Connecting networks...............................................................................................................................461Defining a gateway VTAM........................................................................................................................ 462Defining cross-domain resource managers............................................................................................ 463Defining cross-domain resources........................................................................................................... 465

Session initiation request...................................................................................................................466Name assumption.............................................................................................................................. 467Predefined cross-domain resources without network specification................................................468Predefined cross-domain resources with network specification..................................................... 469Dynamic cross-domain resources..................................................................................................... 470

Defining adjacent SSCPs..........................................................................................................................472Types of adjacent SSCP tables...........................................................................................................472Deciding whether to code adjacent SSCP tables.............................................................................. 472Sample of adjacent SSCP tables for a multiple-network environment............................................ 472Request routing..................................................................................................................................475Dynamically defined CDRSCs and adjacent SSCP tables..................................................................476Alias name translation and adjacent SSCP tables............................................................................ 476

Cross-network routing.............................................................................................................................476Network address structures.............................................................................................................. 476Network naming conventions............................................................................................................ 477Controlling paths for interconnected networks................................................................................ 478Handling class of service tables........................................................................................................ 479Address translation............................................................................................................................481Resource name translation................................................................................................................483Alias selection function of the session management exit routine....................................................484NetView alias name translation facility............................................................................................. 484

Establishing and controlling SNA sessions............................................................................................. 490Nonnative network type 2.1 connections..........................................................................................490Automatic logon................................................................................................................................. 491

Operating VTAM....................................................................................................................................... 492Using the NetView program for network management.....................................................................492

Application programs.............................................................................................................................. 492Defining the NetView program................................................................................................................ 492

Chapter 20. Operating VTAM.............................................................................. 495Starting the domain................................................................................................................................. 495

Configuration restart.......................................................................................................................... 495

x

Information recorded by configuration restart................................................................................. 499Activating resources................................................................................................................................ 499

Order of activation..............................................................................................................................500Resources automatically activated by VTAM.................................................................................... 501Activating application programs........................................................................................................503

Monitoring the domain............................................................................................................................ 504Using the DISPLAY command............................................................................................................504Monitoring I/O problems....................................................................................................................504Suppressing messages...................................................................................................................... 504Message flooding prevention.............................................................................................................505Other methods of controlling messages........................................................................................... 505Displaying and testing routes............................................................................................................ 505Defining operator messages and commands....................................................................................506Multiple console support (MCS) in VTAM.......................................................................................... 506

Controlling the domain............................................................................................................................ 507Establishing and terminating sessions with operator commands....................................................507Dynamic table replacement...............................................................................................................507

Deactivating resources............................................................................................................................ 508Order of deactivation......................................................................................................................... 508Automatic deactivation...................................................................................................................... 508Normal deactivation...........................................................................................................................509Immediate deactivation.....................................................................................................................509Forced deactivation............................................................................................................................509Forced reactivation............................................................................................................................ 509

Halting VTAM............................................................................................................................................509Canceling VTAM....................................................................................................................................... 510Automatic operations.............................................................................................................................. 511

Program operators............................................................................................................................. 511CNM application programs................................................................................................................ 511Collecting session awareness (SAW) data........................................................................................ 512

Operating VTAM in a multiple-domain subarea network....................................................................... 513Links and link stations........................................................................................................................514Discontiguous domains......................................................................................................................516Backing up resource owners..............................................................................................................517

Chapter 21. Tuning VTAM for your environment.................................................. 519Introduction to tuning............................................................................................................................. 519

Tuning tools........................................................................................................................................ 519Estimating active sessions.................................................................................................................520Common storage areas...................................................................................................................... 520Buffer pools........................................................................................................................................ 520Coattailing.......................................................................................................................................... 520

Tuning tools..............................................................................................................................................520Monitoring common storage areas.................................................................................................... 520Analyzing slowdown...........................................................................................................................522Gathering tuning information with the performance monitor interface........................................... 523Gathering tuning statistics.................................................................................................................523Analyzing tuning statistics................................................................................................................. 540Determining the amount of coattailing in your system..................................................................... 541Migrating from user-replaceable constants...................................................................................... 541

Estimating the number of active sessions.............................................................................................. 541EAS operand for application programs..............................................................................................541EAS operand for independent logical units....................................................................................... 542

Common storage areas............................................................................................................................542Common service area limit................................................................................................................ 542Common service area 24-bit............................................................................................................. 542

DISPLAY STORUSE pools.........................................................................................................................542

xi

Buffer pools............................................................................................................................................. 549Types of buffer pools..........................................................................................................................550Buffer pool allocation.........................................................................................................................552HOT I/O detection/termination......................................................................................................... 559

Maximizing coattailing............................................................................................................................. 560Controlling outbound coattailing....................................................................................................... 561Controlling inbound coattailing..........................................................................................................561Coattailing for SNA controllers.......................................................................................................... 562Coattailing for channel-to-channel operations................................................................................. 568

Session-level pacing tuning considerations........................................................................................... 569Input/output buffers.......................................................................................................................... 570Application program data space........................................................................................................570CSM storage........................................................................................................................................570

Appendix A. TSO/VTAM......................................................................................571Defining TSO to VTAM..............................................................................................................................571

Defining the TCAS application to VTAM.............................................................................................571Defining TSO/VTAM session parameters...........................................................................................575Defining an interpret table for compatible logons............................................................................ 580

Defining TSO to MVS................................................................................................................................ 580Writing a procedure to start TSO/VTAM time sharing....................................................................... 580Creating a TSOKEY00 PARMLIB member..........................................................................................580Defining TCAS program properties.................................................................................................... 580

Implementing TSO/VTAM........................................................................................................................580Translation tables...............................................................................................................................581Coding TSO/VTAM exit routines.........................................................................................................581Security...............................................................................................................................................581Performance.......................................................................................................................................5813270 large screen considerations..................................................................................................... 582TSO considerations............................................................................................................................ 582Multicultural support for TSO/VTAM user messages........................................................................ 582Operating VTAM under TSO............................................................................................................... 583

Appendix B. Storage estimate worksheets..........................................................585General information.................................................................................................................................586APPN interchange node or network node...............................................................................................586APPN migration data host and end node................................................................................................ 589Subarea data host....................................................................................................................................590Subarea communication management configuration............................................................................ 591APPL EAS storage estimates................................................................................................................... 593

Appendix C. Communications storage manager.................................................. 595CSM installation and definition................................................................................................................595Initializing CSM........................................................................................................................................ 596Monitoring CSM........................................................................................................................................596CSM problem diagnosis........................................................................................................................... 597

Appendix D. Logon manager...............................................................................599How the logon manager operates........................................................................................................... 599Installing the logon manager.................................................................................................................. 599Starting the logon manager..................................................................................................................... 600Defining the logon manager.................................................................................................................... 600

Sample logon manager configuration................................................................................................600Defining the logon manager and TPF applications to VTAM............................................................. 602Defining the logon manager configuration........................................................................................ 602

Monitoring logon manager resources..................................................................................................... 606Halting the logon manager...................................................................................................................... 606

xii

Appendix E. Cryptographic keys......................................................................... 607Filing SLU keys for single-domain cryptographic sessions.................................................................... 607

Single-domain cryptographic sessions that use PCF/CUSP............................................................. 607Single-domain cryptographic sessions that use ICSF/MVS..............................................................608

Filing CDRM keys for cross-domain cryptographic sessions..................................................................609Cross-domain cryptographic sessions in which both hosts use PCF/CUSP..................................... 609Cross-domain cryptographic sessions in which both hosts use ICSF/MVS..................................... 610Cross-domain cryptographic sessions in which the hosts use different cryptographic services....612Changing the cryptographic capability of a logical unit.................................................................... 614

Appendix F. Command lists: Dynamic configuration of channel-attached devices 615ISTDINFO: VTAM device information services....................................................................................... 615

Dependencies and restrictions.......................................................................................................... 615Output variable...................................................................................................................................615Output tokens.....................................................................................................................................616

ISTDEFIN: VTAM device information services........................................................................................619Dependencies and restrictions.......................................................................................................... 619Output variable...................................................................................................................................620Output tokens.....................................................................................................................................620

Appendix G. Message translation using the MVS Message Service....................... 623Overview of MMS support........................................................................................................................623Internal translation..................................................................................................................................623

Selecting internal translation.............................................................................................................623Defining messages for internal translation....................................................................................... 623

External translation................................................................................................................................. 624Selecting external translation............................................................................................................624Defining messages for external translation.......................................................................................624

Skeleton file use...................................................................................................................................... 625

Appendix H. Forcing an APPN route in a VTAM network.......................................627

Appendix I. Border node connection types......................................................... 631

Appendix J. VTAM restricted materials............................................................... 635

Appendix K. Architectural specifications............................................................ 637

Appendix L. Accessibility................................................................................... 639

Notices..............................................................................................................643Terms and conditions for product documentation................................................................................. 644IBM Online Privacy Statement................................................................................................................ 645Policy for unsupported hardware............................................................................................................645Minimum supported hardware................................................................................................................645Policy for unsupported hardware............................................................................................................646Trademarks.............................................................................................................................................. 646

Bibliography...................................................................................................... 647

Index................................................................................................................ 653

Communicating your comments to IBM.............................................................. 673

xiii

xiv

Figures

1. Pacing flow – outbound pacing...................................................................................................................19

2. Pacing flow – inbound pacing..................................................................................................................... 20

3. Pacing flow – receiving early pacing response...........................................................................................20

4. VTAM network............................................................................................................................................. 22

5. Configuration list......................................................................................................................................... 30

6. MPC connection between two VTAM network nodes.................................................................................45

7. Type 2.1 channel connection between a composite network node and a network node.........................49

8. Leased connection between two composite network nodes.....................................................................50

9. Two network nodes connected using an IBM 3172 Nways Interconnect Controller............................... 51

10. VTAM attachment to a LAN—No meshed connection definitions............................................................53

11. VTAM attachment to a LAN—Meshed connection definitions provide optimal route calculation.......... 54

12. VTAM attachment to a connection network reduces required connection definitions (token ring).......55

13. VTAM attachment to a connection network also enables optimal route calculation (token ring)..........56

14. Basic ATM configuration........................................................................................................................... 59

15. VTAM connection to the IBM Open Systems Adapter..............................................................................60

16. Definition of VTAM connection to the IBM Open Systems Adapter.........................................................61

17. Port on the IBM Open Systems Adapter through which the ATM network is accessed..........................62

18. Definition of port on the IBM Open Systems Adapter through which the ATM network is accessed.....63

19. TGs that route data across the ATM network........................................................................................... 63

20. Definition of a TG over a PVC.................................................................................................................... 64

21. TG over an SVC.......................................................................................................................................... 65

22. Definition of a TG over an SVC.................................................................................................................. 67

23. Multiple nodes communicating across an ATM network......................................................................... 70

xv

24. ATM configuration with a connection network.........................................................................................70

25. Definitions in VTAMLST for the VTAM in HOST1.......................................................................................72

26. Definitions in VTAMLST for the VTAM in HOST2.......................................................................................73

27. Definitions in VTAMLST for the VTAM in HOST3.......................................................................................74

28. APPN subnetworks through APPN multiple network connectivity support............................................ 79

29. VR-based TG between composite network nodes...................................................................................84

30. Multiple contiguous VR-based TGs...........................................................................................................85

31. VR-based TGs in a communication management configuration............................................................. 87

32. Parallel transmission groups in multiple domain environment with NCP............................................... 92

33. XCA multiple domain configuration with Ethernet or Ethernet-type LAN...............................................94

34. XCA multiple domain configuration..........................................................................................................96

35. Comparison between an EE network and a SNA network..................................................................... 101

36. How EE and EBN work together............................................................................................................. 102

37. How ToS settings affect IP traffic........................................................................................................... 106

38. Four types of EE connectivity................................................................................................................. 108

39. VRN connectivity.....................................................................................................................................125

40. VTAM routing with an SATF.....................................................................................................................126

41. VTAM routing meshed connections........................................................................................................127

42. VTAM attachment to a connection network...........................................................................................128

43. VTAM optimal route calculations............................................................................................................129

44. Defining multiple EE VRNs......................................................................................................................131

45. EE connection network reachability awareness in a mixed-release environment............................... 148

46. Connection network reachability example 1......................................................................................... 151

47. Connection network reachability example 2......................................................................................... 151

48. Global VRN with extended border nodes...............................................................................................158

xvi

49. OSA-Express virtual MAC routing........................................................................................................... 172

50. QDIO primary and secondary routing.................................................................................................... 174

51. Creating resources in dynamic switched major node............................................................................178

52. Dynamic configuration of channel-attached device.............................................................................. 181

53. Nonnative network type 2.1 connection................................................................................................ 194

54. Local SNA devices...................................................................................................................................196

55. XCA connection in a single-domain environment..................................................................................198

56. Independent LU with multiple connections to VTAM............................................................................ 206

57. Definition building for dynamically defined dependent LUs..................................................................210

58. Macroinstructions for logon mode table................................................................................................ 217

59. How session parameters are obtained from a logon mode table..........................................................221

60. Automatic logon to A50ACCTS application program............................................................................. 223

61. Automatic logon reallocation................................................................................................................. 225

62. Fixed-session pacing (one- and two-stage)...........................................................................................230

63. Adaptive session pacing......................................................................................................................... 231

64. Pacing windows for SNA LUs.................................................................................................................. 234

65. Pacing windows for non-SNA LUs...........................................................................................................234

66. Same domain application program-to-application program session....................................................237

67. Same domain application program-to-local device session................................................................. 238

68. Application program-to-application program over APPN host-to-host connection.............................240

69. Application program-to-application program over CTCA connection...................................................241

70. Application program-to-local SNA device over CTCA connection.........................................................242

71. Application program-to-local SNA device over AHHC connection........................................................243

72. Applicat