Chapter 9 : Connecting LANs

Spanning Tree

a graph in which there is no loop. In switched LAN, this means creating a topology in which each LAN can be reached from any other LAN through one path only

Backbone Networks

allows several LANs to be connected. In a backbone network, no station is directly connected to the backbone

Bus

the topology of the backbone is a bus

Star

the topology of the backbone is a star. Also known as a collapsed or switched network. It used as a distribution backbone inside a building

Connecting Remote LAN

remotes LAN is another common backbone network application. LANs can be connected using remote bridges

VLAN

Communication between switches

IEEE Standards

Configuration

Advantages

Membership

MAC Address

Port number

IP Address

Multicast address

combination

automatic configuration

semi automatic configuration

manual configuration

table maintenance

frame tagging

time division multiplexig (TDM)

802.1Q defines format of tagging. Also defines format to be used in multi switched backbone and enable using using multi vendor equipment in VLAN

cost and time reduction

creating virtual workgroup

security

Networking Devices

Hub

Bridges

Switch

Router

Gateway

a node on a network that serves as an entrance to another network

Advantages of switch are collision alimination and connecting heterogeneous devices

Two Layer

– provide many ports and allow better performance. It can be more sophisticated. Can have buffer to hold the frames for processing

Three Layer

A switch that can perform routing functions

device that operates only in the physical layer

Active

Passive

a multi-port repeater and it create connection between station in physical star topology

a connector that connect wires coming from different branches

operates at physical level which is regenerate the signal it receive and also data link level which is can check physical (MAC) address consist in the frame

a router is use when user wants to connect multiple networks and forward packets destined either for its own networks or other networks