Title: Networking and Internetworking Devices
1Networking and Internetworking Devices
- Repeaters
- Bridges
- Routers
- Gateways
- Routing Algorithms
2Homework
3(No Transcript)
4Connecting Devices and the OSI Model
5Repeater and OSI Model
6A Repeater
7Function of a Repeater
8Bridge and the OSI Model
9Bridges
- Reduces Collision Domain / Congestion
- Simple
- Addresses manually entered
- Multiport
- Transparent
- Builds routing table itself
- Updates table based on source addresses
10A Bridge
11Function of a Bridge
12Router and the OSI Model
13Routers in an internet
14Routing Concepts
- Least cost routing
- Hop count
- Link-quality
- Speed, congestion, link medium
15Routing concepts
- Non-adaptive
- Adaptive
- Packet Lifetime
16Gateway and the OSI Model
17A Gateway
18Gateway
- Each Side Unaware of The OTHER
- Protocol Converter
- SNA -gt TCP/IP
- AppleTalk -gt TCP/IP
- Novell Netware -gt TCP/IP
19Other Devices
- Multi-Protocol Routers
- IPX, TCP/IP
- Brouter
- Router if known protocol
- Bridge otherwise
20Switches
- Function at Level 2
- Bridging Capability
- Store and Forward
- Telex
- Cut-Through
- Immediate Transfer
21Routing Switches
- Function as routers
- Faster than traditional routers
- USE Level 3 Network Addresses
22Distance Vector Routing
- Knowledge about the entire network
- Routing only to neighbors
- Information Sharing with neighbors
23Link State Routing
- Knowledge of neighborhood
- Shares with all routers flooding
- Information sharing when change
24Dijkstra Algorithm
- Breadth Search from root
- Select lowest cost
- Add node and arc
25Routing Classifications
- Adaptive routing (dynamic)
- Non-adaptive routing (fixed or static)
26Dynamic Routing Algorithms
- Distance Vector Routing
- Link state routing
27Routing Algorithms
- Distance Vector Routing
- Each link is assigned a weight
- Distance to the destination is the sum of the
weights along the path to the destination
28Routing Algorithms
- Distance Vector Routing
- Each router sends its entire information about
the entire network to its neighbors. - Neighbors are other routers with direct link to
it. - Information are shared periodically, even if
nothing has changed. - Eventually, every router will learn about other
routers on the network. - Slow convergence (it takes longer for all routers
to receive all information)
29Distance Vector Routing Protocol
- RIP (Routing Information Protocol)
- Each router uses broadcasting to send its entire
information to its neighbors every 30 seconds. - The best path is based on the least number of
hops. - Its suitable for small networks
- RIP is used by IPX/SPX and TCP/IP.
30Distance Vector Routing Table
31Routing Algorithms
- Link state routing
- If there is a change, each router sends its
information about its neighbors to every other
router in the network using flooding. - A router, periodically sends a message to its
neighbors, the response indicates that the device
is alive and functioning. - No response, change has occurred.
32Link State Routing Protocol
- OSPF (Open Shortest Path First)
- More efficient than RIP
- Only the changes are sent
- each router sends its information about its
neighbors to every other router in the network
using flooding. - A router, periodically sends a message to its
neighbors, the response indicates that the device
is alive and functioning. - No response, change has occurred.
33Concept of Link State Routing
34Costs in Link State Routing
35Link State Packet
36Flooding of As LSP
37Flooding of Bs LSP
38Link State Database
39Finding the Shortest Path
- Select a node (A) and make it permanent
- Examine each of the adjacent nodes to A.
- Relabel each one with the distance to A.
- Make the one with the smallest label permanent.
(14) - This becomes the new working node.
40Costs in Dijkstra Algorithm
41Shortest Path Calculation
42Shortest Path Calculation
43Shortest Path Calculation
44Shortest Path Calculation
45Shortest Path Calculation
46Shortest Path Calculation
47Shortest Path Calculation
48Shortest Path Calculation
49Shortest Path Calculation
50Shortest Path Calculation
51Shortest Path Calculation
52Shortest Path Calculation
53Shortest Path Calculation
54Link State Routing Table for A