Generic AAA* basedBandwidth on Demand

* Authentication Authorization & Accounting

EVL at UIC meetingChicago 18/10/2002

Leon GommansAdvanced Internet Research Group

University of Amsterdamlgommans@science.uva.nl

Content- Goals and basic list of requirements.

- Lightpath and Lightpath control concepts

- Generic AAA concepts

- High level design and operation of proof of concept.

- Example of a simple request message and policy.

- Next work items

Goal- Allow a provisioned Lightpath to by-pass a regular internet connection. Internet connection becomes control channel.

Motivation:- Routed networks are too expensive if requested bandwidth is in the order of the traffic generated by a nations NRN -TCP stack & transport channel needs tailored behavior to make optimal use of a high speed ( GB ), high delay (>100ms) channel- Modifications generates Internet “unfriendly” TCP traffic.- Firewalls do (not yet) statefully inspect 10 GB/S streams without delays or performance implications.- Single Packet drop causes severe performance hits.- Memory buffers in routers/switches are a concern when the road gets smaller.

Rough requirements list.- Allow lightpath usage in a “demand driven” fashion.- Allow “hard” or “soft” pre-allocation.- Must support allocation and usage across multiple domains.- Must be integrated into middleware e.g. by allowing provisioned by-pass model to be supported by GridFTP. Raised this with GGF Data Transport RG (Bill Allcock).- Allow authorized VO’s or individual users to discover available lightpaths (e.g. via a OGSA/WS style interface).- Allow authorized users (with a certain role within the VO) to pre-allocate and use bypass for a limited amount of time and with limits on the allocated bandwidth.- Must integrate with existing authentication & user (role based) authorization system: Looking into EDG VOMS.

Rough requirements list.- Must hide complexity from user. Conceptually the

user must perform the process in 3 basic steps after login:1) Pre-allocate either manually or automatically thru

a scheduling system -> system issues an authorization.

2) Allow the job to allocate the network resource whereby it uses the authorization.

3) Once the job is finished, the authorization is handed back so resources can be freed.

- User (or scheduling system) must be allowed to change the reservation if the process flow so dictates.

- Allocating user may be different from ultimate user.- Allocating user may subdivide capacity amongst

users.- Must ultimately support Grid Economic Services

Architecture features to allow ad hoc creation.- Must ultimately provide Grid Accounting records for

billing in contract situations.

Design considerations. - Group in Amsterdam does focus on deploying Generic

AAA (RFC2903/RFC2904) concepts to handle authorization of lightpath. Group members were authors.

- Best suited to handle policy based authorization in a dynamic fashion either to build AuthZ tokens or process requests which contain AuthZ tokens. Note AuthZ may itself also contain policies.

- Authorizations between administrative domains must be done at a fairly high-level.

- Don’t want to address low level networking problems (path finding/setup) as vendors and researchers like ICAIR are already active in this area

- Need to identify role, messages and policies that are handled by Generic AAA components as part of the overall “workflow”.

Lightpath

Def*: Any uni-directional point to point connection with effective guaranteed bandwidth

Examples of LightPaths:* Analog wavelength on a CWDM or DWDM system* STS channel on a SONET or SDH circuit* ATM CBR circuit* Diff serv “gold” service on a packet based network* Gigabit Ethernet over dedicated fiber strand

* Definition by Bill St. Arnoud of Canarie

Onion Lightpath modelSelectorSwitch

DistributorSwitch

SelectorSwitch

DistributorSwitch

Domain X

Domain Y

Domain XDomainY

Daisy Chain Lightpath model

Domain B Domain C

Domain A

Domain D

Daisy Chain & Onion

Domain B Domain C

Domain A

Domain D

Domain X Domain X

Domain X

DomainY

Onion control modelSeectorSwitch

DistributorSwitchDomain X

Domain Y

AAA

Domain AAA engine must controlboth selector and distributor switch andInterconnecting network

Daisy chain control modelSelectorSwitch

DistributorSwitchDomain A Domain B

AAA

Domain AAA engine must control the selectoror distributor switch and one of the AAA Serversmust control intermediate network

AAA

Generic AAAo 5 years ago a AAA server was known as a server supporting dail-in boxes thru the RADIUS protocol (at IETF).o IETF42 (in same hotel as GGF6) held first AAA BOF as it wasrecognized AAA could be used in other type of applications.o Amsterdam group has been participating on defining concepts for Generic AAA since march 1999 when AAA WG was formed at IETF-44o Work became IRTF subject end of 1999 (AAA ARCH RG).o ID’s that became RFC’s 2903 – 2906 were submitted after the Adelaide IETF march 2000. RFC’s describe framework, architecture, example applications and requirements.o Optical Networking within grid environment is a research application for Generic AAA.

RFC 2904 Generic AAA Framework basic principles

3 fundamentally different user initiated authorization sequences. Note: RFC2904 does not show step 5 – service access.

Service

AAA

User

Service

AAA

User

Service

AAA

User

Pull sequence

NAS (remote access)RSVP (network QoS)

Agent sequence

Agents, Brokers,Proxy’s.

Push sequence.

Tokens, Tickets,AC’s etc.

1

11

2 2

2

33 3

4

4

4

Generic AAA Framework

Separating the User Awareness from the Serviceyield Roaming Models: Example roaming pull model.

Service

AAA

User1 2 5

6

AAA

3 4

User HomeOrganization

ServiceProvider

Generic AAA Framework

Distributed Services Models allow many typesand combination of authorization sequences ..

Service

AAA

User

AAAUser HomeOrganization

ServiceProvider A

Service

AAA

ServiceProvider B

AAAClient

Generic AAA Architecture – RFC2903

PolicyDecision

Point

PolicyEnforcement

Point

Fundamental idea’s inspired bywork of the IETF RAP WG thatin RFC 2753 describes a framework for Policy-basedAdmission Control.

Foundation for COPS

The point where policy

decisions are made.

The point where the policy

decisions are actually enforced.

RequestDecision

PolicyRepository

Basic Goal Generic AAA: Allow policy decisions to be made by multiple PDP’s belonging to different administrative domains.

Generic AAA Architecture – RFC2903

ApplicationSpecificModule

PolicyEnforcement

Point

Archieve goal by by separatingthe logical decision process fromthe application specific partswithin the PDP.

RequestDecision

RuleBasedEngine

PolicyRepository

PDP

Example of Generic AAA Architecture – RFC2903

ApplicationSpecificModule

BandwidthBroker

RuleBasedEngine

PolicyRepository

ApplicationSpecificModule

RuleBasedEngine

PolicyRepository

Users

ApplicationSpecificModule

RuleBasedEngine

PolicyRepository

ContractsBudgets

Registration Dept.Purchase Dept.

Bandwidth Provider

AAAServer

AAAServer

AAAServer

(Virtual) User Organization

QoS EnabledNetwork

Use

r

Service

Service Organization

802.1QVLANSwitch

EnterasysMatrix E5

A

B

C

D

802.1QVLANSwitch

EnterasysMatrix E5

1 GB SX

AAA

192.168.1.5

iGrid2002

Policy DBAAARequest

192.168.1.6

192.168.2.3

192.168.2.4

Generic AAA (RFC2903) based Bandwidth on Demand

802.1QVLANSwitch

EnterasysMatrix E5

A

B

C

D

802.1QVLANSwitch

EnterasysMatrix E5

1 GB SX

AAA

192.168.1.5

iGrid2002

Policy DBAAARequest

192.168.1.6

192.168.2.3

192.168.2.4

Generic AAA (RFC2903) based Bandwidth on Demand

Next Setup using vendor provided network provisioning system

802.1QVLANSwitch

EnterasysSS6000

A

B

C

D

802.1QVLANSwitch

EnterasysSS6000

Managed Optical Connection Service

AAA BoDServ

IP A

IP B

IP C

IP DCisco CTM

Example XML Lightpath request<AAARequest version="0.1" type="BoD" >  <Authorization>      <credential>         <credential_type>simple</credential_type>         <credential_ID>JanJansen</credential_ID>         <credential_secret>#f034d</credential_secret>      </credential>  </Authorization>  <BodData>      <Source>192.168.1.5</Source>      <Destination>192.168.1.6</Destination>      <Bandwidth>1000</Bandwidth>      <StartTime>now</StartTime>      <Duration>20</Duration>  </BodData></AAARequest>

Policy (significant part) executed by AAA Rule Based Engineif( ( ASM::RM.CheckConnection( Request::BodData.Source, Request::BodData.Destination ) &&

( Request::BodData.Bandwidth <= 1000 ) ))then( ASM::RM.RequestConnection( Request::BodData.Source, Request::BodData.Destination, Request::BodData.Bandwidth, Request::BodData.StartTime, Request::BodData.Duration ) ; Reply::Answer.Message = "Request successful")else( Reply::Error.Message = "Request failed")

Design Detailso Onion model was chosen for first implementation.o Single AAA engine controls both ingress and egress switch by creating 802.1Q VLAN’s using the dot1Q Bridge MIB extentions via SNMP.o 1 GB channel between switches carry 802.1Q tagged ethernet frames. An 802.1Q trunk can carry up to 4096 VLAN’s.o End stations register with AAA engine and subsequently send request to reach other stations (pointed to via its public IP address).o By-pass communication channel uses a private IP address space. Destinations are identified by main IP address.

Technical Implementationo XML/SOAP messages for request/reply (to prepare for a future web services interface)

o RBE: JAVA code running as Servlet. Uses Apache Axis to handle SOAP messages.

o ASM: JAVA code currently running in Java context of RBE. Currently investigating how it could run separately e.g. as Java Bean or using CORBA.

o More technical details: Bas van Oudenaarde: oudenaar@science.uva.nl and Arie Taal: taal@science.uva.nl

Upcomming work:

1) Separate ASM and RBE and allow ASM’s to be loaded/unloaded dynamically.

2) Implement pre-allocation mechanisms (based on GARA – collaboration with Volker Sander).

3) Create ASM for other B/W manager (e.g. Alcatel BonD, Cisco CTM, Level-3 Ontap)

4) Create ASM to talk to other domain: OMNInet5) Allow RBE’s to talk to each other (define

messages).6) Integrate BoD AAA client into middleware eg by

allowing integration with GridFTP and integration with VOMS authentication and user authorization system.

7) Build WS interface abstraction for pre-allocation and subsequent usage.

Thank you !

Lgommans@science.uva.nl