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Telecomm/Data Network
A telecommunication/Data network is composed from many network elements (switching systems, terminals, circuits etc.) which provides certain services for the users. The collection of such elements forms the system resources.
Heterogeneous (Platforms/Protocols)
Complex (Many layered)
Service Management (Fast service setup)
WIMAX
Access Metro Core
3000R
OA
DM
6500
View of a Telecomm/Data Network
6100
(MSAP)
GPON
IPDSLAM
GbE
Access Networks
Optical Transport Pa
ck
ets
Management
Access Networks
Optical Transport Pa
ck
ets
OSP OLT
R-ONT
R-ONT
R-ONT
R-ONT
R-ONT
VoIP
ISP Peering
Internet
Video
Services
100FX
ADSL2+
VDSL2
GbE
ADSL2+
VDSL2
PSTN
2x 10 GE
/ OC48
Network Management Systems
A network management systems are used to control the system and its resources by controlling its usage, access monitoring and reporting its current and historical status.
Judgment, forecasting, decision making, analyzing data, and make positive efforts to maintain quality of service.
Overview: Network Management
AgentAgent Agent
Agent
Collect, organize & interpret
Operational DataAdministrator
Workstation
Management Platform
Observation
& Control
mgmt requests/replies
event reports
Agent Agent
Agent
OAM&P(operations, administration, maintenance, and provisioning)
Provisioning
- Planning
- Design
Network Management
Defined As OAMP (Operations, administration, maintenance and provisioning) of
Network and Services
Goal Main goal of Network Management is to ensure that the users of the
network receives the information technology services with the QoS that they expect.
SLA – Formally or Informally – Operation Critical Services should be un-interrupted 24x7 and other non – critical 8x5
From business administration point of view network management involves strategic and tactical planning of engineering, operation and maintenance of network services for current and future needs.
Network Management Function Network Provisioning, operations, I&M
Systems and Network Management SNMP 6
Network Management Operation
Network Provisioning Network planning & Design; Responsibility of engineering group
Keep track of new technologies and apply based on analysis of network traffic and performance data collected through network operations.
Use Network Management Tools
Network Operations NOC is responsible for discharging ISO defined five OSI network
management applications – fault, configuration, performance, security & Accounting
Fault Management
Accounting Management
Configuration Management
Performance Management
Security Management
Systems and Network Management SNMP 7
Fault Management Fault : A fault is an abnormal condition that requires management attention
for repair whereas error is a single event. A fault is usually indicated by failure to operate correctly or by excessive errors. For example if a communication line is physically cut no signal will get thru so that there is persistently high bit error rate.
Fault Management Is the process of locating faults
Related to service failure
Main Steps Discover the problem
Isolate the problem
Fix the problem (if possible)
How do we do it Trouble Ticket (I&M group)
Systems and Network Management SNMP 8
Accounting Management Accounting Management
NOC administers costs and allocates the use of the network
Measure the usage of network resources and services
Involves tracking individual’s utilization and grouping of network resources to ensure users have sufficient resources
Involves granting or removing permission for access to the network
The reason to do accounting
An end user or group of users may be abusing their access privilege and burdening the network at the expense of others
An end user may be making inefficient use of the network
Network Managers can plan better growth of the network if user behaviour is know.
Systems and Network Management SNMP 9
Configuration Management Config Mgmt is related to initializing the network and gracefully shutting it
down. Manage the behaviour of devices thru software. Same device could be used as router or end device with the help of software with set of attributes and values.
Configuration Management
Configuration of network devices controls the behavior of the network.
Process of finding and setting up these critical devices
Three types of configurations – Static or permanent, Dynamic or current & Planned
NOC has displays which shows dynamic configurations of the network and its status
Shows Failure points, traffic patterns and performance
Systems and Network Management SNMP 10
Performance Management Performance Concerns
What is the level of network utilization
Is there excessive traffic
Has thruput has been reduced to unacceptable limits
Are there any bottlenecks
Is response time increasing
Taken care thru monitoring & control
Performance Management Involves measuring the performance of the network hardware, software and media
NOC gathers data and keep it upto date to perform above stated objective as well as tune the network for optimum performance.
Examples of measured indicators are – network traffic/overall throughput, network availability/percentage utilization, Error rates, Response time/delays.
Traffic analysis is useful in detecting trends and future planning, performance data on availability and delay is useful for tuning the network and increase the reliability and improve the response time.
Systems and Network Management SNMP 11
Security Management
Security Management Is the process of controlling access to the information on the network
Provides a way to monitor access points and records information on a periodic basis
Provides audit trails and sounds alarms for security breaches
A security database is established and maintained by the NOC for access to network and network information.
Generating, distributing & storing encryption keys
Password and Access control and Authentication
Audit logs Security records
Enabling disabling logging services.
Systems and Network Management SNMP 12
Overview: Network Management
AgentAgent Agent
Agent
Collect, organize & interpret
Operational DataAdministrator
Workstation
Management Platform
Observation
& Control
mgmt requests/replies
event reports
Agent Agent
Agent
OAM&P(operations, administration, maintenance, and provisioning)
Provisioning
- Planning
- Design
Network Management Standards
OSI (CMIP/CMISE) International standard (ISO/OSI)
Data communication networks (LAN/MAN)
Deals with all seven layers
Most complete
Object oriented
Well structured and layered
Complex and consume large resources
Internet Model Industry standard (IETF)
Originally intended for internet components (routers/switches), currently adopted for WANs and Telecomm
Easy to implement/Most widely deployed
Systems and Network Management SNMP 14
Network Management Standards
TMN International standard (ITU-T)
For Telecomm/based on OSI NM model
Addressed both network management and administrative aspects
IEEE LAN/MAN IEEE standard adopted internationally
Addressed management of LANs/MANs
First two layers of OSI model/based on OSI model
Web-based management Web-based Enterprise Management
Java Management Extensions (JMX)
Systems and Network Management SNMP 15
Network Management Models
OSI network model proposes following four management models
Organizational Model Defines Components of network management system, their function & infrastructure
Defines terms object, manager, agent
ISO I0040
Informational Model Structure & Organization of Management Information
ISO I0165 defines SMI & MIB (Structure of management information & management information database)
SMI – how management information is structured
MIB – relationship and storage of information
Communication Model Mode of communication between the entities of organization models
Functional Model Configuration, Fault, Performance, Accounting & Security
Systems and Network Management SNMP 16
Network Management Models
Organizational Model
Consists of Managers, Agents and Managed Objects
MDB
Two-tier & Three-tier systems
MoM
Three-tier EMS systems
NMS systems
Systems and Network Management SNMP 17
Network Management Models
Information Model
Structure & Storage of Information, e.g. ISBN – “ISBN”, “Chapter”,”Figure”
Specifies the information base to describe managed objects & their relationship
SMI – Syntax & Semantics of management information
MIB – storage of SMI data (used by both manager & agent)
MIB v/s MDB, i.e. meta-data v/s real data
Example data of MIB
Network elements : hubs, bridges, routers, transmission facilities
Software Processes : programs, algorithms, protocols, databases
Administrative information : contact person, account numbers
Systems and Network Management SNMP 18
Management Information Trees
MIT Managed objects are uniquely defined by a tree structure specified by OSI model
Root Node and well defined nodes underneath each node at different levels
Each managed object = a node in the tree
Containment model
Systems and Network Management SNMP 19
ISO-ITU (2)ISO (1)
org (3)
dod(6)
internet(1)
ITU (0)
Managed Object Perspective
Internet Perspective
Access:
Access privilege
Systems and Network Management SNMP 20
Object Type:Object ID & Descriptor (Unique ID & Name of object type)
Syntax:Model of object
Definition:Textual description of object
Status:Implementation Requirements
Managed Object Perspective
ISO Perspective
Systems and Network Management SNMP 21
Object Class:Circular Object
Attributes:Circle, dimensions
Behaviour
Attributes:ellipse, dimensions
Operations:Push
Object Class:Elliptical Object
Notification:Notify changes in attribute values
Managed Object (ISO/IETF)
Characterstics Example
Object Class Packet Counter
Attributes Single-valued
Operation Get,set
Behaviour Retrieve or reset values
Notification Generate notification on change
Systems and Network Management SNMP 22
Characterstics Example
Object type PktCounter
Syntax Counter
Access Read-only
Status Mandatory
Description Counts no. of pkts
Network Management Models
Communication Model
The way information is exchanged between the systems
Three important aspects are defined here
Transport medium of message exchange (transport protocol)
Message format of communication (application protocol)
The actual messages (commands & responses)
Connectionless or Connection-oriented (TP4 over X.25 or IP)
Systems and Network Management SNMP 23
Manager Application
Manager Communication Module
Transport Layer
Agent Communication Module
Agent Application
Transport LayerUDP/IP (IETF)OSI Layer (OSI)
SNMP (IETF)CMIP (OSI)
Oper/req/res/traps/notifications
Network Management Models
Functional Model Fault Management
Configuration Management
Performance Management
Administration Management
Security Management
Systems and Network Management SNMP 24
Network Management Cost Models
Response Time Evaluations
Asynchronous polling
Synchronous polling
tdel,i = average network latency delay between the manager and ith agent
tp = average processing time for handling a single request/response message
tcomp = computation time to process the collected data
Find out the overall response time for both the modes
Systems and Network Management SNMP 25