Advanced Network Management

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Advanced Network Management

• Instructor Dr. Dssouli
• Acknowledgement
• Thanks to Dr. Chadi Assi who develepped this
  course

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Text Books and References

• Network Management Principles and Practice Mani
  Subramanian, Addison Wesley,
• ISBN 0-201-35742-9
• SNMP, SNMPv2, SNMPv3 and RMON1 and 2
• William Stallings, 3rd edition, Addison Wesley,
  ISBN 0-201-48534-6
• Network Management A Practical Perspective
  Leinwand, A. and Fang K., Addison Wesley
• Essential SNMP
• Douglas Mauro and Kevin Schmidt, OReilly
• online version http//www.unix.org.ua/orelly/
  networking_2ndEd/snmp/
• Other RFCs and Research papers

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Course Outline

• Network Management Principles, Standards and
  Models.
• Computer Networks and the Internet
• Application, Transport and Network layer
• Network Management Protocols and Abstract Syntax
  Notation One (ASN.1).
• Simple Network Management Protocol (SNMP)
• Structure of Management Information (SMI),
  Management Information Base (MIB).
• SNMPv2
• SNMPv3
• Remote Monitoring (RMON), RMON 1 and 2.

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Course Outline

• OSI Systems management, Telecommunications
  Management Network (TMN), and ATM Network
  Management. .
• Network Management Applications (Configuration,
  Performance, Fault and Security management).
• Distributed Management Framework (management by
  delegation, mobile agent based management, etc.)
• CORBA based management, web based management, JMX
  and DMTF.

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Course Outline

• Marking Scheme
• Midterm1         35
• Midterm2         35
• Project/Report            30
• More infohttp//users.encs.concordia.ca/dssouli
  /INSE-7120.html

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Background

• Todays Information Infrastructure (or simply
  the Internet) is increasingly growing
• large number of interconnected heterogeneous
  sub-networks and a wide range of distributed
  applications (100s or 1000s of interacting
  hardware/software components)
• Other complex systems requiring monitoring,
  control
• jet airplane
• nuclear power plant
• Others
• In such a large network, many things can go wrong
  
• therefore disabling the network or a portion of
  it and degrading performance to an unacceptable
  level!

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Background

• During the old days, a network can be managed by
  using only human efforts!
• In a small system, running few pings may help
  locating the problem
• As the Internet becomes a large global
  infrastructure, automated network management
  tools are essential
• Standardized tools that can be used across a
  broad spectrum of product types are also needed
• Therefore, a network management system (NMS) is a
  collection of tools for network monitoring and
  control
• Just as an airplane cockpit allows a pilot to
  monitor, control, analyze, configure, etc.

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Network Management

• Failure of Interface Card
• A network admin by monitoring and analyzing
  network traffic may detect problems in any
  interface card and replace it
• e.g., increase in checksum errors in frames sent
  out by this interface
• Host Monitoring
• A network admin periodically checks to see if all
  hosts are operational

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Network Management

• Monitoring traffic/resource deployment
• By monitoring link utilization, a network admin
  may determine system bottleneck and provision
  higher bandwidth link instead, to avoid
  congestion

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Network Management

• Rapid changes in routing tables
• If detected may prevent instabilities in routing
  and hence prevent a network from going down
• Intrusion detection
• Network admin requests to be notified when
  traffic is destined to/arrives from a suspicious
  source
• Detect the existence of a certain type of traffic
  (e.g., security attacks)

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What is Network Management?

• "Network management includes the deployment,
  integration and coordination of the hardware,
  software, and human elements to monitor, test,
  poll, configure, analyze, evaluate, and control
  the network and element resources to meet the
  real-time, operational performance, and Quality
  of Service requirements at a reasonable cost."

T.Saydam, T. Magendaz From Networks and Network
Management into Service and Service Management
Journal of Networks and System Management, Vol.4,
No.4, Dec. 1996
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More recent Definition

• Network Management refers to the activities,
  methods, procedures and tools pertaining to the
  operation, administration, maintenance and
  provisioning of networked systems
• Alex Clemm Network Management Fundamentals,
  Cisco Press, 2006

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What are the managed systems?

• It can be
• Network or Network of networks
• Equipment and Devices
• End systems such as distributed systems or
  applications (often called distributed systems
  management)
• Services ( service provider), known as service
  management

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What a general management system does?

• Observe facts (collect data, measure
  parameters...)
• Analyze data collected and behaviour
• Act on the managed system to obtain results

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What is Network Management?

• ISO (International Organization for
  Standardization) has created a network management
  model. 5 areas of network management are
  classified
• Performance Management
• Fault Management
• Configuration Management
• Security Management
• Accounting Management
• This classification has gained broad acceptance
  by vendors of both standardized and proprietary
  NMS

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Performance Management

• Goal
• Quantify, measure, report, analyze, and control
  the performance of different network components
  (such as routers, hosts, as well as end to end
  abstractions, such as a path through the network)

• Two functional categories
• Monitoring (ability to monitor and track
  activities on the network)
• Controlling (ability to make adjustments to
  improve network performance).
• Measuring Performance
• Throughput (whether reduced to unacceptable
  level!)
• Response time (i.e. network delays)
• Utilization
• Error rates (identify bottlenecks)
• Availability

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Fault Management

• Goal
• Log, detect, and respond to fault conditions in
  the network
• Immediate handling of transient network
  failures (link, host, router hardware or software
  outages)

• Faults are to be distinguished
• from Errors
• A fault is an abnormal condition and requires
  management attention to repair (e.g. link cut)
• An Error is a single event! (e.g. single bit
  error on a line)

performance management takes longer term view in
the face of varying traffic demands and
occasional network device failures.
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Illustrative scenario

• A client application exchanges data over a TCP
  connection with a DB server
• Distinct domains each administered by a different
  organization

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Illustrative scenario

• Problem scenario
• A clock at an interface in WAN2 that supports
  T3 link loses SYNC 4 times a second for 0.25 ms
• ? intermittent noise causing loss of 0.1 of T3
  capacity
• ? this small noise causes bit errors in a large
  number of packets routed over C-D
• ? Bit errors cause packet losses, either at
  routers (if IP header corrupted) or at
  destinations

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Illustrative scenario

• ? performance of TCP connection degrades due to
  packet loss
• ? TCP sender interprets this as congestion and
  hence reduces its window
• TCP increases its window gradually until new
  packet loss
• However due to the noise, the TCP window will not
  increase
• DB transactions by client will last longer
• DB server performance will degrade due to records
  lock-out, causing frequent aborts for remote
  transactions

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Configuration Management

• Consists of the following steps
• Gather information about current network,
  maintain an up-to-date inventory of all network
  components
• Use that data to modify the configuration of the
  network device (reconfiguration)

• Goal
• Allow a network manager to track which devices
  are on the network and the hardware and software
  configurations of these devices.

Reconfiguration of a network is often desired
in response to performance evaluation or in
support of network upgrade, fault recovery, or
security checks.
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Security Management

• Security at different levels
• Physical Data Link Levels ? Encryption
• Network Level ? packet filters
• Application Level ? (host, user and key)
  authentication
• Popular Level ? Firewalls VPNs

• Goal
• Control access to network resources according to
  well defined policy.
• Identifying sensitive information (e.g., network
  management information) and protecting it

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Accounting Management

• A network manager should track the use of network
  resources
• A user may be abusing his access privilege and
  burdening the network at the expense of other
  users. (e.g., a user may be violating his service
  contract)
• Planning for network growth

• Goal
• Specify, log, and control user and device access
  to network resources
• usage quotas, usage-based charging, the
  allocation of resource-access privileges
• Accounting reports should be generated
  periodically

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Infrastructure for Network Management
definitions
managing entity
managed devices contain managed objects whose
data is gathered into a Management
Information Base (MIB)
managed device
network management protocol
managed device
managed device
managed device