Details about syntax,protocols and network

Details about syntax,protocols and network

Syntax and semantics of a protocol.

Ans:

The Key elements of Protocol are:

Syntax: What is communicated?

It refers to the structure of data It includes data format, coding and signal levels

Meaning the order in which the data is represented.

For example: 1st eight bit to the sender address.

Next eight bit to the receiver address.

The rest is the data

For Example:

• First eight bits to the Sender’s Address.
• Next eight to be Receiver’s Address.
• The rest to be data.

Semantics: How it is communicated?

It refers to the meaning of each section of bits. It includes control information for coordination and error handling. How is a particular pattern to be interpreted?

What action should be taken based on interpretation?

For Example:

• Does an address identify the route to be taken or the final destination of the message?
• Performance and reliability of a network.

Ans:

Performance:

It can be measured in many ways including Transit & Response Time. The performance depends on the following factors;

1. Number of USERS
   1. The large number of concurrent users slow network.
   2. Design of network.
   3. Peak load periods.
   4. Network Criteria.
2. Type of Transmission Medium.
   1. Medium defines speed at which data can travel.
   2. Fiber Optic Cable.
   3. 100Mbps and 10 Mbps.
   4. Hardware.
   5. Software.
3. Hardware
   1. Effect speed and the capacity of transmission.
   2. Fast computer with large storage capacity.
   3. Software
   4. Network Criteria.
4. Software
   1. Software process data at sender, receiver and intermediate nodes.
   2. All communication steps need software.
   3. Moving message from node to node.
   4. Transforming.
   5. Processing at the sender and receiver.
   6. Error free delivery.

Reliability:

The reliability depends on the following factors;

1. Frequency of failure.
2. Recovery Time of a network after failure.
3. Catastrophe
4. Fire, Earthquake or Theft.
5. Spatially shared and time shared in multipoint line configuration.

Ans

• Spatially Shared MultipointLineConfiguration:

If several devices can share the link simultaneously, it is called Spatially Shared Line Configuration.

• Time Shared Multipoint Line Configuration:

If users must take turns using the link, it is called Time or Temporal Shared Line Configuration

Circuit switch and packet switch network.

Circuit Switch Network:

A dedicated communication path is established between two stations through the nodes of the network. This path stays up for the duration of the communication.

Example: Telephone Network.

• Packet Switch Network:
  1. No capacity is dedicated along a path through the network.
  2. Data is sent out in small chunks called “Packets”.
  3. Each path is passed from node to node.
  4. At each node, entire packet is received, stored briefly and then transmitted to the next node.

Example:Computer to Computer Communication.