Topology

The way of cabling is called topology.
The architecture of a network is called topology
There are 2 Topologies : 

1) Network Topologies
2) Logival Topologies Network Topologies: 

E.g.: Bus, Star, Ring, and Mesh Topologies.
Bus Topology: 
Components of Bus Topology:
1. Co-axial cable (back bone cable)
2. T- connectors
3. BNC (British Network Connector)
4. Terminator
5. Patch cable

Disadvantages of Bus:

If anything goes wrong with backbone cable whole network is down.
Follows a serial communication.
Outdated these days.

Star Topology: 

Star topology is an advanced version over bus topology. Where it uses either a hub or a switch, it uses cat5/6 cables.
It uses connecters called (Recommend Jack) - RJ45
Star topology offers faster data transfer or processing.
Ring Topology: 
Ring topology is useful when we want redundancy (fault tolerance) we go with this type of topology.
Ring topology uses a device called MSAU. (Multi Station Access Unit)
It is a unit inside which a logical ring is formed. This ring ensures the availability of Network. The availability of ring ensures availability of network.
It was basically implemented in IBM networks.

Logical Topologies: 

There are 2 types:
1)Work Group
2)Domain

Workgroup (peer to peer): 
1 Collection of computers connected together to share the resources.
2 No servers are used.
3 Only Client OS is mostly used.
4 Any O/S like, DOS, 95, 98, workstation, win 2000 pro, and XP pro can be configured as work-group model.
5 Suitable for smaller organizations.
6 Where security is not the criteria.
7 No administrator is required
8 Where we are not using client server based applications. Like oracle, SQL and exchange etc.

Domain (Client/Server): 
Domain is a collection of computers connected together with a server and users
Domain model can have servers like UNIX, Novell NetWare, WIN-NT server, 2000 server, and 2003 server.
Provides centralized administration.
Suitable for medium to large size networks/organizations.
Suitable when we have client server architecture (Back ends & front ends)
Domain offers security and provides logon authentication.
Suitable if security is criteriaRequires an administrator.