Ans:
There are two types of transmission technology.
i) Broadcast Network.
ii) Point-to-point Network.
i) Broadcast Network :
Broadcast networks have a single communication channel that is shared by all the machines on the network.
Broadcasting systems generally allow the possibility of addressing a packet to all destinations by using a special code in the address field. When a packet with this code is transmitted, it is received and processed by every machine on the network. This mode of operation is called broadcasting.
Use : Smaller, geographically localized networks tend to used.
There are two broadcast network/topology.
This are :
(i) Bus Topology/Network.
(ii) Ring Topology/Network
1. Buys Topology :
Bus networks use a single networking
or connecting wire called backbone to which all the node or computers
are peripheral devices are attached.
Advantages :
i) Easier to construct
ii) Cheaper than to other networks
iii) Less noise in data transmission.
Disadvantages :
i) If one computer or backbone is demaged than whole system/network failed.
ii) More management cost.
2. Ring Topology :
The ring topology connects the nodes of
network in a circular chain with each node connected to the next. The
final node in the chain is connected the ring.
Advantages :
i) Connection structure is simple
ii) Less costly to other network.
iii) Less chance of collision.
Disadvantages :
i) It is unreliable.
ii) If the connection is broker than the network is collapse.
2. Point-to-point Network :
Point-to-point Networks consist of many connections between individual pairs of machines.
To go from source to destination, a packet on this type of network may have to first visit on or more intermediate machines.
Often multiple routes of different lengths are possible, so routing algorithm play an important role in point-to-point networks.
Use : Layer networks usually are used to point-to-point network.
These are :-
1. Star Topology
2. Tree Topology
3. Mesh Topology
4. Hybrid Topology
1. Star Topology :
In this topology all computers arev
connected to a central switch called HUB. A HUB is the central
centrolling device.
Advantages :
i) Intelligent HUB can monitor traffic and helps to privent collision.
ii) In star topology broker, connection cannot effect the whole network.
Disadvantages :
i) If the HUB is demaged the whole network collapse.
2. Tree Topology :
Tree is used multipoint link. Nodes ia a
tree are linked to a central HUB that controls the traffic to the
network. Not every devices plug directly into the central HUB. Majority
devices are connected to secondary HUB.
Advantages :
i) Les expensive than mesh topology.
ii) Easy to installation and reconfigureation.
iii) Include robustness.
iv) Easy to fault isolation and fault identification.
Disadvantages :
i) More cable is reguired than ring and bus topology.
3. Mesh Topology :
The types of topology where each nodes are directly connected with another nodes.
Advantages :
i) Most reliable.
ii) Each computer is connected another without any disturbing.
Disadvantages :
i) Costly
ii) Difficult to construct.
4. Hybrid Topology :
Here, a pure star or ring or
completely connected network is rarely used. Instead, an organization
will use some sort of hybrid network,which is a combination of two or
more different network topologies.
Advantages :
i) It is reliable.
ii) Less cheaper of collision.
Disadvantages :
i) More expensive
ii) Difficult to construct.