In the Name of the Most High
New Trends in Network Management
by
Behzad Akbari
Fall 2011
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Need for new management technologies
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Since late ’80s
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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
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Devices simple, resource constrained
Capabilities were limited
Today
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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
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Management of large backbone networks requires
powerful configuration management
Move from device management approach to system
management
Service centric view of network

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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
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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
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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
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Revised OBJECT definitions
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Improved tables
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counter64 type
unambiguous row selection
procedures for creation and deletion of rows
augmenting of tables
Notification definition
Manager-manager communication
SNMP v3 - Security
Drawbacks of SNMP
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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
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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
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Improving SMI
Improving SNMP protocol
Enhancing configuration management
capability
Evolutionary efforts - I
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Internet Research Task Force (IRTF) and Network
Management Research Group (NMRG) developed
SMIng
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IETF was to develop a standards track for above in 2000
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Allows arbitrarily nested data structures
Facilitates re-usability of complex data structures
Extensible mechanisms
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
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Attempt to improve protocol shortcomings
Efforts to reduce overhead due to OID redundancy
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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
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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
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Communication model
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Defines how the management information is represented,
data structures, objects etc. Eg., SNMP/UDP/IP is
management protocol and SMI for definition of data
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
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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
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Web based management
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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

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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
Web Interface
Desktop PC
HTTP
Web Browser
NMS Console
Web Server
SNMP Manager
NMS
SNMP Agent
SNMP
Managed Objects
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Figure 14.1 SNMP NMS with Web Interface
Proxy Server
Desktop PC
HTTP
Web Browser
Web Server
Manager
Applications
Proxy Server
SNMP / Other
Agent
SNMP/
Other
Managed Objects
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Embedded WBM
Workstation/PC
Web Browser
Manager
Applications
HTTP
Web Server
Managed Objects
Figure 14.3 Embedded WBM Configuration
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Web based & SNMP
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Devices have an embedded web server as well as
SNMP agent (dual interface)
Combines the advantages of both approaches
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Manager agent paradigm
Efficient Fault and Performance monitoring capability offered by
SNMP
Detailed configuration
Map based end-to-end view
Desktop Management Interface
Desktop Resident
Management Applications
Management Interface (MI)
API
Service Layer (SL)
Component Interface (CI)
MIF DataBase
Hardware/Software Components
MIF: Management Information Format
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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
Request/Confirms
Indications
MIF Access
Management Interface
Synchronization and Flow Control
Component Interface
Response/Confirms
Command
Processing
MIF Set
MIF Install
MIF
DataBase
Events/Response
Event
Processing
MIF Processing
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DMI Functions
MI Interface
Client
Local Block
Interface
Application
Indication
Server
MI Interface
Client
RPC Support
Indication
Server
RPC Support
RPC to/from
Remote Systems
Data Block Mgmt
Interface
RPC SUPPORT
Management Interface Server
Indication Client
SP/MIF
Database
DMI Service Provider
Data Block Component
Interface
Block CI
Component
(HW/SW)
Procedural Component Interface
Procedural CI
Hardware
Component
Procedural CI
Software
Component
Figure 14.6 DMI Functional Block Diagram
Procedural CI
Firmware
Component
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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
private
{1 3 6 1.4}
enterprises
(1)
dmtf
(412)
dmiMIB
(1)
dmiObjects
(1)
dmiNotification
(2)
dmtfStdMifs
(2)
dmtfDynOids
(3)
dmiConformance
(3)
Figure 14.7 DMI MIB
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Web-Based Enterprise Management
Web Client
Desktop PC
SNMP Agent
Web Browser
DMI Agent
Management
Applications
CIM Agent
HTTP
CIM
Object Manager
(CIMOM)
HTTP
CIM
Schema
HTTP
HTTP
SNMP Provider
DMI Provider
SNMP
RPC
SNMP
Managed Objects
CIM
Managed Objects
DMI
Managed Objects
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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
Management
Applications
Snap-in
Snap-in
COM/DCOM
IWbemServices
MOF Language
COM/DCOM API
CIM Object Manager
Repository
COM/DCOM
IWbemServices
Object Providers
WMI
SNMP
RPC
Win 32
WMI
Objects
SNMP
Objects
DMI
Objects
Win 32
Objects
Other
Objects
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Figure 14.10 WMI Architecture
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)
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New Management Technologies
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TeleManagement Forum(TMF) Interfaces
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MTNM
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NML-EMS interface based on CORBA
MTOSI
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OS-OS interface based on XML
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