Session 02
Network Components
MJ02/0704
Adapted from Network Management: Principles and Practice © Mani Subramanian 2000 and solely used for Network
Management course at Universitas Bina Nusantara
1
Technology and Management
• What are the technologies that need to
managed?
• Challenges of technological progress on
network management
MJ02/0704
2
Computer Network Technology
• Network comprises
• Nodes
• Links
• Topology: How they’re configured
• LAN
• WAN
MJ02/0704
3
LAN
•Type of LANs
• Ethernet
• Fast Ethernet
• Gigabit Ethernet
• Half-duplex vs Full-duplex
• Switched Ethernet
• VLAN
• Token ring
• FDDI
• ATM / LANE
MJ02/0704
4
WAN
• Facilities / Media
• Wired: Copper, Coaxial, Fiber
• Wireless: Terrestrial, Satellite
• Mode: Digital, Analog
• Services: POTS, ISDN, Broadband
MJ02/0704
5
Nodes
• Hubs
• Bridges/Remote bridges
• Routers
• Gateways
• Switches
MJ02/0704
6
Network Node Components
Dial-up
Network
Router
Switched
Hub
External
Network
Gateway
ATM
Switch
Hub
Bridge
External
Network
Remote
Bridge
Workstation
Hub
Router
Hub
• Hub
• Bridge, Remote bridge
• Router, Gateway
• Switch
MJ02/0704
7
Basic Network Nodes
ATM
ATM
ATM Switch
Local LAN
Ethernet
Packets
Filter
Local Network
IP Packets
Filter
Routing
Bridge
Routing
External LAN
Ethernet
Packets
External Network
IP Packets
Router
IP
Network
Packets
Format
change
X.25
Network
Packets
Gateway
MJ02/0704
8
Basic LAN Topologies
DTE
DTE
DTE
Ethernet
DTE
DTE
• Bus topology
• Used in Ethernet LAN family
• Common shared medium
• Randomized access (CSMA/CD)
• Easy to implement
• Lower utilization under heavy traffic 30%-40%
• Single culprit could effect the entire LAN
MJ02/0704
9
Basic LAN Topologies
DTE
DTE
DTE
DTE
• Ring Topology
• Used in token ring and FDDI
• Shared medium
• Deterministic access
• Master DTE has control
• High utilization >90%
MJ02/0704
10
Star & Hybrid LAN Topologies
DTE
DTE
DTE
DTE
DTE
DTE
DTE
DTE
DTE
DTE
DTE
DTE
DTE
DTE
Ethernet Hub
Token Ring Hub
• Star topology used with bus and ring topology
• Hub is “LAN in a box”
• What does the electronic LAN inside the box
look like?
• Why has hub become so popular?
MJ02/0704
11
WAN Topologies
N1
N2
N2
N1
N3
N4
Mesh Topology
N5
N3
N6
N4
N5
N6
Tree Topology
• Mesh topology
• Implemented in network layer level
• Multiple paths between nodes
• Flat topology, Redundancy, Load balancing, Shortest path
• Tree topology
• Used with Ethernet bridges
• Hierarchical
• Efficient for small networks and, special purpose networks
MJ02/0704
12
Transmission Technology
Transmission Technology
Medium
Wired
LAN
Mode
Wireless
Digital
Analog
WAN
LAN Mobile Satellite
• Physical transport media
• UTP
• Coax
• Fiber
• Terrestrial wireless
• Satellite transmission
MJ02/0704
13
Transmission Modes
Bandwidth
Time
Division
Multiplexing
(TDM)
Channel
channel 1
channel 2
channel 30
Time
User 30
User 1
User 2
User 3
User 4
Time
Cell
Multiplexing
Bandwidth
E1 Time Division Multiplexing (TDM) Transmission
Time
Cell Transmission (ATM)
MJ02/0704
14
LAN Data Rate
Ethernet
10Mbps
FDDI
100 Mbps
Fast Ethernet
100Mbps
Gigabit E’Net
1 Gbps
MJ02/0704
ATM
155.52 Mbps
ATM
STM-n
15
Hubs
DTE
DTE
DTE
DTE
Patch Panel
Hub
Wiring Closet
• Hub is a platform
• Function dependent on what is housed
• LAN (Bus/Ethernet)
• Switched LAN (Ethernet)
• Bridge
MJ02/0704
16
Hub 1
Backplane
Interconnection
To DTEs
Stacked Hubs
Hub 2
• Hub ports can be scaled up using stacked hubs
• Stacked hub
• extend back plane
• connected as daisy chain
MJ02/0704
17
Switched Ethernet
DTE
DTE
DTE
DTE
Switched
hub
DTE
DTE
DTE
DTE
• Maximum throughput increased ~N/2 in N-port hub
• Snooping capability lost for management
MJ02/0704
18
Client/Server Using Switched Hub
Server
100 Mbps
Switched hub
10 Mbps
Workstation
MJ02/0704
10 Mbps
Workstation
10 Mbps
Workstation
19
Router
Network A
Protocol P
Network B
Protocol P
Router
Protocol interface
TP
TP
NP
NP
NP
NP
DP
DP
DP'
DP'
Phy
Phy
Phy'
Phy'
Physical medium A
Physical medium B
• Routes packets between nodes of similar network protocols
• Routing table used to route packets
• DLC and Physical layers could be different under the same
common network layer protocol
MJ02/0704
20
Gateway
Network A
Protocol P
Network B
Protocol Q
Gateway
Protocol interface
TP
TP
NP
NP
NP'
NP'
DP
Phy
DP
DP'
DP'
Phy
Phy'
Phy'
Physical medium
• Gateway is router connecting two networks with dissimilar
network protocols
• Gateway does the protocol conversion at the network layer
• Protocol converter does the conversion at the application layer
MJ02/0704
21
Switched Networks
Pkt1
Pkt2
Pkt3 Pkt2 Pkt1
DTE A
Pkt3
B
A
Pkt3 Pkt2 Pkt1
D
DTE Z
C
Virtual Circuit Configuration
• Switches are embedded in bridges and routers
• Switched network used in WAN
• Two types of switched networks
• Circuit-switched
• Packet-switched
• Datagram service
• Virtual circuit
MJ02/0704
22
Switched Networks
Pkt3 Pkt2 Pkt1
DTE A
Pkt1
Pkt3
Pkt2 Pkt3 Pkt1
B
Pkt2
A
Pkt2
D
DTE Z
Pkt2
C
Datagram Configuration
MJ02/0704
23
Broadband Services
Residential
Customer
Network
Service
Providers
Campus
ATM / LAN
Network
MJ02/0704
Broadband
Access
Gateway
STM-n
Broadband
Access
Residential
Customer
Network
SDH WAN
STM-n
Campus
ATM / LAN
Network
24
Broadband Services
• Integrated services: Voice, video, and data
• Narrow band ISDN (Integrated Services Digital
Network)
• Basic rate:2B + D (B channel 64 kbps and
D channel 16 kbps
• Primary rate: 23B + D channels
• Broadband Services
• ATM
• SDH (Synchronous Digital Hierarchy)
• Access technologies:
• HFC (Hybrid Fiber Coaxial) / Cable modem
• ADSL (Asymmetric Digital Subscriber Line)
MJ02/0704
25