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In the Name of the Most High
New Trends in Network Management
Need for new management technologies Since late ’80s
Networks have evolved Management needs have changed Management technologies have evolved
Mismatch in speed of evolution of networks and management requirements vis a vis management technology
Evolution of networks
In the mid-late ’80s Devices simple, resource constrained Capabilities were limited
Today Increased functional complexity Increased complexity in configuration Increased intelligence and programmability of
devices Networks that provide a wide range of services NGNs: Packet based networks for all services Providing unfettered access for users to networks
and to competing service providers for services of their choice
Source: ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005
Source: ITU-T Workshop on NGN (jointly organized with IETF) Geneva, 1-2 May 2005
Changes in operator needs Management of large backbone networks requires
powerful configuration management Move from device management approach to system
management Service centric view of network
VoIP (residential and business), multimedia streaming, IP TV, fast data connectivity, triple play
Increased speed of service delivery Automation of business processes
Consequences for management
Rethinking management principles – integration of independent developments
Management support for delivering quality service Changes resulting from “user” focus as opposed to
“network” focus Importance of developing standardized management
software for easy maintenance and extensibility
Traditional approaches - Datacomm
SNMP based Aim was to have simple small footprint protocol Kept self contained and independent of other network
services Catered to fault, performance monitoring, simple
configuration management Soon after release, shortcomings were exposed
Key revisions in SNMP v2, v3
Revised OBJECT definitions counter64 type
Improved tables unambiguous row selection procedures for creation and deletion of rows augmenting of tables
Notification definition Manager-manager communication SNMP v3 - Security
Drawbacks of SNMP
Inadequate information modeling – simple data structures and protocol operations
Object based rather than object oriented No inheritance – so no information re-use Inadequate primitive for bulk information retrieval UDP transport restricts size of data that can be sent Limited configuration management support Low level semantics
Configuration management needs Need to apply configuration changes to several network
devices simultaneously Download bulk configuration changes on many devices Schedule configuration operations on devices at
particular times Roll back support Co-ordinated activation of downloaded configurations
Overcoming SNMP shortcomings
Evolutionary efforts were made to address shortcomings Improving SMI Improving SNMP protocol Enhancing configuration management
capability
Evolutionary efforts - I
Internet Research Task Force (IRTF) and Network Management Research Group (NMRG) developed SMIng Allows arbitrarily nested data structures Facilitates re-usability of complex data structures Extensible mechanisms
IETF was to develop a standards track for above in 2000 Phase 1: requirements drawn up Phase 2: 2 strong proposals emerged
Efforts to merge these failed, in 2003, group was wound up
Evolutionary efforts - II
Attempt to improve protocol shortcomings Efforts to reduce overhead due to OID redundancy
Compression Suppression of redundant OID fragments Effect bulk transfer at MIB level instead of OID
Use of TCP as transport protocol Did not meet with success because of industry
reluctance to accept new technology
Evolutionary efforts - III
COPS PR for improving Configuration Management capability
Resource Allocation Protocol (RAP) –WG for policy based configuration and provisioning
Specification language: Structure of Policy Provisioning Information (SPPI)
TCP is transport protocol Intends to make configuration changes based on PBMS
Selecting a management technology Information model
Defines how the management information is represented, data structures, objects etc. Eg., SNMP/UDP/IP is management protocol and SMI for definition of data
Communication model Defines protocol for exchange of management information,
structure of PDU, protocol operations Specifies how units of management information can be
addressed Organizational model
Actors, roles and principles of co-operation whether manager-agent, management by delegation, mobile agents, policy based etc.
Selecting a management technology
Efficiency and timeliness Simplicity Cost of development and maintenance Maturity Security Overhead on managed equipment (CPU,
memory footprint etc.) Bandwidth overhead
Characteristics of management data
MFA Realtime Bulk Read/Write
Fault Yes Yes Read
Performance Yes Yes Read
Configuration No Yes Read/Write
Security Yes Yes Read
Alternative management approaches Web based management embedded web server in device Browser can connect to to the URL of the device and
html pages with management information Provides graphical displays of management
information Improved configuration facility, detailed device
management Drawbacks
More an EMS-like approach – no end to end view High level management functions such as map based
view, root cause analysis, trend analysis not supported
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Web Interface
NMS
SNMP Manager
Managed Objects SNMP Agent
Web Server
Web Browser
NMS Console
Desktop PC
Figure 14.1 SNMP NMS with Web Interface
SNMP
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Proxy Server
Proxy Server
ManagerApplications
Managed Objects SNMP / OtherAgent
Web Server
Web Browser
Desktop PC
Figure 14.2 Proxy Server with Web Interface
SNMP/Other
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Embedded WBM
ManagerApplications
Managed Objects Web Server
Web Browser
Workstation/PC
Figure 14.3 Embedded WBM Configuration
HTTP
Web based & SNMP Devices have an embedded web server as well as
SNMP agent (dual interface) Combines the advantages of both approaches
Manager agent paradigm Efficient Fault and Performance monitoring capability offered by
SNMP Detailed configuration Map based end-to-end view
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Desktop Management Interface
Service Layer (SL)
Management Interface (MI)
Component Interface (CI) MIF DataBase
MIF: Management Information Format
Desktop ResidentManagement Applications
Hardware/Software Components
API
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Desktop Management Interface (DMI)
Industry standard generated by - Desktop Management Task Force (DMTF)
Started in 1992 to manage PCs Manages both hardware and software Two standards
Management information format (MIF), similar to MIB
Program interface with two APIs
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DMI Service Layer
Synchronization and Flow Control
Management Interface
Component Interface
MIF Access
MIF Set
MIF Install MIF DataBase
Request/Confirms
Response/Confirms Events/Response
Indications
CommandProcessing
EventProcessing
MIF Processing
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DMI Functions
DMI Service Provider SP/MIFDatabase
Management Interface Server
RPC Support
MI InterfaceClient
IndicationServer
RPC Support
MI InterfaceClient
IndicationServerLocal Block
InterfaceApplication
Data Block MgmtInterface
RPC SUPPORT
Indication Client
Data Block ComponentInterface
Procedural Component Interface
Block CIComponent(HW/SW)
Procedural CIHardware
Component
Procedural CISoftware
Component
Procedural CIFirmware
Component
RPC to/fromRemote Systems
Figure 14.6 DMI Functional Block Diagram
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DMI MIB
enterprises(1)
dmtf(412)
dmiMIB(1)
dmtfStdMifs(2)
dmtfDynOids(3)
dmiConformance(3)
dmiNotification(2)
private{1 3 6 1.4}
dmiObjects(1)
Figure 14.7 DMI MIB
• MIF specified using ASN.1 syntax• Can be managed by an SNMP manager• DMTF task expanded to specify WBEM -
Web-based enterprise management• DMTF
- Distributed Management Task Force
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Web-Based Enterprise Management Web Client
SNMPManaged Objects
DMI Managed Objects
DMI ProviderSNMP Provider
CIMObject Manager
(CIMOM)CIM
Schema
ManagementApplications
Web Browser
Desktop PC
HTTP HTTP
HTTP
SNMP RPC
CIM Managed Objects
HTTP
Figure 14.8 WBEM Architecture
SNMP Agent
DMI Agent
CIM Agent
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Web-Based Enterprise Management
WBEM based on Common Information Module
CIM is information-modeling framework intended to accommodate all protocols and frameworks
Object-oriented Five components:
Web client CIM object manager (CIMOM) CIM schema Management protocol Managed objects with specific protocol
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Microsoft WMI
CIM Object Manager RepositoryMOF Language
COM/DCOM API
Object Providers
WMIObjects
WMI
SNMPObjects
SNMP
DMIObjects
RPC
Win 32Objects
Win 32
OtherObjects
COM/DCOMIWbemServices
ManagementApplications
Snap-inSnap-in
COM/DCOMIWbemServices
Figure 14.10 WMI Architecture
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Microsoft WMI
• WMI is Microsoft infrastructure to support WBEM CIM
• WMI comprises management infrastructure, applications, and agents
• CIMOM has plug-in management applications• COM/DCOM API specifies interface to CIMOM• CIM is the CIM schema• Object providers are management agents (e.g.
SNMP agent)
New Management Technologies
TeleManagement Forum(TMF) Interfaces MTNM
NML-EMS interface based on CORBA MTOSI
OS-OS interface based on XML
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