Network Management - Introduction

1
Network Management - Introduction
2
References

• Communications Network Management, Kornel Terplan
  Prentice Hall 1992, 2nd ed.
• Managing Inter networks with SNMP Mark A. Miller,
  M T books 1999, 3rd ed.
• SNMP, SNMPv2, SNMPv3 and RMON1 2, William
  Stallings, 3rd ed. Addison Wiley 1999
• Telecommunications Network Management into the
  21st century techniques, standards,
  technologies, and applications, New York IEEE
  Press

3
References - contd

• How to Manage your Network Using SNMP, Marshall
  T. Rose and Keith McCloghrie
• The Simple Book, Marshall T. Rose
• A Practical Guide to SNMPv3 and Network 8.
  Management, David Zeltserman, Prentice Hall.
• Network Management Principles and Practice,
  Mani Subramanian, Adddison Wesley Press
• Network Management, A Practical Perspective,
  Allan Leinwand and Karen Fang Conroy, Addison
  Wesley

4
Introduction

• What is Network Management?
• Managing Networks - is the network
• Performing optimally
• Troubleshooting
• Reconfiguring - configuration
• Expanding
• Secure
• Accounting, Usage
• Planning

5
What if no NM?

• What is the latest configuration?
• What are the systems and what is their capacity?
• Not up to speed? Where is the bottleneck?
• High delays under certain conditions? Why is it
  happening?
• Permissions, access?
• Security?

6
Strategic Importance of Network and Network
Management

• 1970s decade of centralized networks
• 1980s
• More LANs
• Interconnected LANs
• Distributed computing

7
Contd.

• Current
• Gigabit speeds
• SONET
• WANs
• Web based technologies
• Various architectures
• Wireless proliferation

8
NM Functional Groupings
9
Network Dependency

• Business
• Commercial
• Education
• Research
• Defense
• Integration of these sectors

10
Network Dependency

• Failure of networks
• Inefficient operation
• Heavy Downtime costs and Loss

11
Factors affecting NM systems
12
Complexity of Network Management

• Management by Human effort
• Automated tools
• Large networks - heterogeneous equipment
•        cost and complexity higher
•        need for standardized tools
• management Staff

13
Is NM crucial?

• Better control higher level of network
  performance
• Better performance higher productivity
• Higher productivity financial stability and
  improvement
• (Continuous improvements in network management
  necessary)

14
contd

• How to cope with new applications?
• New Systems?
• Controlling complexity
• Improving services
• Balancing needs
• Reduce downtime
• Controlling costs

15
NM?

• CEO
• financial management of the corporate
  communications network
• USER
• Availability
• Reliability
• Performance
• Stability
• Security
• Simplicity in accounting

16
Critical Success Factors for NM

• Process and procedures
• Steps and guidelines on how to use the necessary
  tools to execute network management
• Instruments
• Hardware software for data collection and
  processing
• Human Resources
• NM personnel

17
Process and Procedures

• Configuration Management
• Fault Management
• Performance Management
• Security Management
• Accounting
• Planning

18
Configuration Management

• Middle and long range activities for controlling
• physical, electrical and logical inventories
• maintaining vendor files
• supporting provisioning and order processing
• managing changes
• distributing software

19
Fault Management

• Dynamically maintain network service level
• High availability
• Quick recognition of problems performance
  degradation
• Log control information distribution
• Fault Isolation
• Reconfigure / Modify to minimize impact
• Repair /Replace failed components

20
Performance Management

• Ongoing evaluation of network service level
  maintenance
• Identify bottlenecks (potential)
• Check level of capacity/ utilisation?
• Check delays
• Check for unusual network behaviour

21
Security

• Ongoing protection of network
• Protection of Network Components
• Entry to network
• Access to Services
• Transfer of information from network
• Risk analysis minimizing
• Implementing security plans
• Monitoring Success of strategies

22
Accounting

• Process of
• Collecting
• Interpreting
• Reporting on
• Costing and charging oriented information on
  resource usage
• Processing of accounting records, bill
  verifications, charge back procedures

23
contd

• Resources subject to accounting
• Communication facilities
• Hardware usage
• Software usage
• Other services
• Security and Accounting depend on Company Policies

24
Planning

• Off line management, based on collected
  statistics, corporate level decisions, network
  designers, user requirements demands
• Involves dimensioning a networks
• Depends on
• Network traffic
• Resource utilization
• Networking requirements
• Technological trade-offs
• Estimated growth technology
• Growth of user population

25
Monitoring and Control

• Network Monitoring
• Observing and Analysing the status and behaviour
  of the end-systems, intermediate systems and
  sub-networks
• Three major functions
• Design monitoring mechanism
• Access information for monitoring
• Apply monitored information

26
Types of monitored information

• Static Information
• Related to current network configuration
• Infrequent information change
• Dynamic Information
• Related to events
• Statistical
• Derived from dynamic information

27
Relationship
28
Monitoring and Control

• Network Control
• Modifying parameters and causing actions to be
  taken by the end systems, intermediate systems,
  sub-networks

29
Physical and Logical Network management

• Physical
• Problem detection
• Failure notification on
• Physical entities
• Circuits
• Devices
• Multiplexers etc

30
Contd.

• Logical
• Monitoring and management of
• Logical Connections
• Session awareness
• Traffic flow monitoring

31
In summary NM

• NM is continuing process
• Data identification
• Extraction
• Collection
• Maintenance
• Analysis
• Interpretation
• For Control and Management

32
NM architecture - Manager / Agent Model
33
Contd..

• Management System
• Houses a Manager Application
• Management Database
• Manager Application
• Interface between Network manager (human) and the
  devices being managed
• Could be GUI based
• There could be a number of manager applications
  and Management Systems

34
Contd..

• Managed System
• Has the Agent process
• Managed Objects
• Management Database
• Management Information Database
• There could be a number of Managed Systems

35
Contd..

• Agent Process
• Collects statistics on communication and network
  related activities
• Store statistics locally
• Respond to commands from network
• Transmit collected statistics to network control
  centre
• Change a parameter
• Provide status information
• Generate artificial traffic pattern to perform a
  test

36
Contd..

• Agent Process
• Send messages to the Manager Process when local
  conditions undergo significant changes
• Notifications

37
Contd..

• Monitoring Agent
• Module that generates summaries and statistical
  analyses of management information

38
Managed Objects

• Entities which need to be monitored and
  controlled
• TCP connection
• Packets
• Time
• CPU
• Link

39
Management Information Base (MIB)

• MIB is a virtual data Information base. It is
  compiled into the manager and Agent application.
  It is static
• Management database contains the measured values
  associated with the Managed object. It is dynamic

40
MIB structure

• Tree structure with root
• Branches managed objects by logical categories
• leaves managed objects

41
Management Protocol

• Sets up communication protocol between manager,
  agents and managed objects
• Commands
• Responses
• Notifications

42
Techniques of monitoring

• Polling
• Request-response interaction
• Manager queries for variables
• Agent responds
• Request reports with matching criteria

43
Techniques of monitoring

• Event Reporting
• Agent Initiated
• Manager is listener
• Periodic Events
• On occurrence of significant or unusual event

44
Polling or Event Reporting

• Either or combination
• Amount of traffic generated
• Robustness in critical situations
• Time delay in notification
• Amount of processing in managed devices

45
Typical Manager Agent configuration
46
NM in the OSI model

• NM resides at the Application layer