Session 01
Network Overview
MJ01/0704
Adapted from Network Management: Principles and Practice © Mani Subramanian 2000 and solely used for Network
Management course at Universitas Bina Nusantara
1
Data and Telecommunication Network
Data communication network
Terminal
Terminal
Host
Modem
Modem
Modem
Voice
Voice
Telecommunication network
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Data and Telecommunication Network
• Computer data is carried over long distance by
telecommunication network
• Output of telephone is analog and output of
computers is digital
• Modem is used to modulate and demodulate
computer data to analog format and back
• Clear distinction between the two networks is
getting fuzzier with modern multimedia networks
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Telephone Network
• Characteristics:
• Reliable - does what is expected of it
• Dependable - always there when you need it
• Good quality (connection) - hearing each other well
•Reasons:
• Good planning, design, and implementation
• Good operation and management of network
• Automatic routing
• Fault management
• Use of Operations Systems to ensure QoS
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Operations Systems / NOC
• Monitor telephone network parameters
• S/N ratio, transmission loss, call blockage, etc.
• Real-time management of network
• Trunk (logical entity between switches) maintenance
system measures loss and S/N. Trunks not meeting
QoS are removed before customer notices poor quality
• Traffic measurement systems measure call blockage.
Keep the call blockage below acceptable level
• Operations systems are distributed at central offices
• Network management done centrally from Network
Operations Center (NOC)
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IBM SNA Architecture
Workstation
Workstation
Cluster
Controller
Communination
Controller
Cluster
Controller
Communication
Controller
Mainframe
• IBM System Network Architecture (SNA) is a major step in
network architecture
• SNA is based on multitude of (dumb) terminals accessing a
mainframe host at a remote location
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Distributed Computing Environment
Host
Workstation
Workstation
Ethernet
Workstation
Host
Hosts and Workstations on LAN
• Driving technologies for DCE:
• Desktop processor
• LAN
• LAN - WAN network
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LAN-WAN Network
LAN A
LAN B
Bridge /
Router
Bridge /
Router
Bridge /
Router
LAN C
WAN
communication link
• Major impacts of DCE:
• No more monopolistic service provider
• No centralized IT controller
• Hosts doing specialized function
• Client/Server architecture formed the core of DCE network
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Client/Server Model
Request
Client
Control
Transfer
Server
Control
Transfer
Response
Simple Client-Server Model
• Client always initiates requests
• Server always responds
• Notice that control is handed over to the receiving entity.
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TCP/IP Based Networks
•
•
•
•
TCP/IP is a suite of protocols
Internet is based on TCP/IP
IP is Internet protocol at the network layer level
TCP is connection-oriented transport protocol and
ensures end-to-end connection
• UDP is connectionless transport protocol and
provides datagram service
• Internet e-mail and much of the network mgmt.
messages are based on UDP/IP
• ICMP part of TCP/IP suite
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Internet Configuration
Mail Server
Workstation
Workstation
LAN A
Domain
Name
Server
LAN B
Router
Router
Router
LAN C
Gateway
WAN
Gateway
LAN X
Router
Router
Router
LAN Y
LAN Z
Mail Server
Workstation
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PC
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SNA, OSI, and Internet
SNA
End User Application
OSI
INTERNET
Application
Presentation
Presentation
Data Flow Control
Session
Transmission Control
Transport
Application Specific
Protocols
Transport
SNICP
Path Control
Network SNDCP
Network
IP
SNDAP
Data Link
Data Link
Physical
Physical
Not Specified
• Similarity between SNA and OSI
• Simplicity of Internet; specifies only layers 3 and 4
• Integrated application layers over Internet
• Commonality of layers 1 and 2 - IEEE standard
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Architecture, Protocols and Standards
• Communication architecture
• Modeling of communication systems, comprising
• functional components and
• operations interfaces between them
• Communication protocols
• Operational procedures
• intra- and inter-modules
• Communication standards
• Agreement between manufacturers on protocols
of communication equipment on
• physical characteristics and
• operational procedures
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Communication Architecture
User A
User Z
Peer-Protocol Interface
Application Layers
Application Layers
Transport Layers
Transport Layers
Physical Medium
Direct Communication between End Systems
System A
Intermediate system
System Z
User A
User Z
Peer-Protocol Interface
Application Layers
Application Layers
Transport Layer
Transport Layers
Conversion
Physical Medium
Transport Layers
Physical Medium
Communication between End Systems via an Intermediate System
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Communication Architecture
• Inter-layer interface: user and service provider
• Peer-layer protocol interface
• Role of intermediate systems
• Gateway: Router with protocol conversion as
gateway to an autonomous network or subnet
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Application Protocols
Internet User
OSI User
VT
TELNET
FTP
FTAM
SMTP
MOTIS
CMIP
Presentation Layer
OSI user
Virtual Terminal
File Transfer Access & Mgmt
Message-oriented Text Interchange
Standard
Common Management Information
Protocol
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SNMP
Terminal
Applications
File Transfer
Mail Transfer
Management
Applicationst
Transport Layer
Internet user
Telnet
File Transfer Protocol
Simple Mail Transfer Protocol
Simple Network Management
Protocol
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Common Network Problems
• Loss of connectivity
• Duplicate IP address
• Intermittent problems
• Network configuration issues
• Non-problems
• Performance problems
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Network Management
Network
Management
Network
Provisioning
Planning
Design
Network
Operations
Network
Maintenance
Fault Management /
Service Restoration
Fault Management
Configuration Management
Performance Management
/ Traffic Management
Trouble Ticket
Administration
Network Installation
Security Management
Network Repairs
Accounting Management
Facilities Installation
& Maintenance
Routine Network
Tests
Reports Management
Inventory Management
• OAM&P
• Operations
• Administration
• Maintenance
• Provisioning
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Data Gathering & Analyses
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NM Functional Flow Chart
Network
Users
Management
Decision
New
Technology
Configuration
Data
TT
Restoration
Performance
& Traffic Data
Engineering Group
- Network Planning &
Design
Operations Group NOC
- Network Operations
I & M Group
-Network Installation &
Maintenance
Fault
TT
Installation
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NM Components
NMS
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Network
Agent
Network
Agent
Network
Objects
Network
Objects
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Interoperability
NMS
Vendor A
Messages
Services & Protocols
NMS
Vendor B
Network
Agent
Network
Agent
Network
Agent
Network
Agent
Network
Objects
Network
Objects
Network
Objects
Network
Objects
• Message exchange between NMSs managing different domains
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Status and Future Trends
• Status:
• SNMP management
• Limited CMIP management
• Operations systems
• Polled systems
• Future trends:
• Object-oriented approach
• Service and policy management
• Business management
• Web-based management
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Challenges of IT Managers
• Reliability
• Non-real time problems
• Rapid technological advance
• Managing client/server environment
• Scalability
• Troubleshooting tools and systems
• Trouble prediction
• Standardization of operations - NMS helps
• Centralized management vs “sneaker-net”
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