Datagram Switching and Virtual Control Switching

Datagram Switching and Virtual Control Switching of Switching Chapter of Data Communication and Networking System

1. Datagram Network and Virtual Circuit Network Name: Mustak Ahmmed Roll: 160134 Dept.: Computer Science and Engineering Jashore University of Science and Technology

2. Datagram Network Routing Table Efficiency and Delay of Datagram Network Virtual Circuit Network(VCN) Three Phases of VCN Efficiency and Delay of VCN Contents

3. A datagram is a basic transfer unit associated with a packet-switched network. It provides a connectionless communication service across a packet-switched network. Internet is done by using packet transfer approach at network layer. Packet may be dropped because of none reservation system. There is no resource reservation. Datagram Networks

4. Datagram Networks Diagram

5. A switch in a datagram network uses a routing table that is based on the destination address. Destination Address: The destination address in the header of a packet in a datagram network remains the same during the entire journey of the packet. Routing Table

6. Routing Table Diagram

7. The efficiency of a datagram network is better than circuit-switched network. Resources are allocated only when there are packets to be transferred. All the switches are being used in this network which is connected with receiver end directly or indirectly. Efficiency

8. There are four types of delay in this network. i.e. Processing Delay: time required to process a packet. Queueing Delay: time spent waiting in a queue at any point along the route. Propagation Delay: time for one bit to propagate from source to destination. Transmission Delay: time to send out / absorb all of the packet bits. Delay

9. Delay Diagram The Total Delay = 3T + 3 +  

10. A virtual circuit network is a cross between a circuit switched network and a datagram network. V arying packet queue lengths in the network nodes. It is normally implemented in the data link layer. Virtual Circuit Network

11. Virtual Circuit Network Diagram

12. There are two types of addressing, i.e. Global Addressing: An address that can be unique in the scope of the network. Virtual-Circuit Identifier(VCI): That is a small number has only switch scope. When a frame arrives at a switch, it has a VCI; When it leaves it has a different VCI. Shown in below figure- Addressing

13. Switch and Table in Virtual Circuit Network Diagram

14. Setup Phase: Creates an entry for the virtual circuit; Data Transfer Phase: T ransfer a frame from a source to its destination . It will stay until all the frames transfer finished. Teardown Phase: The switch deletes corresponding entry after transfer data from their table. Three Phases

15. Setup Request Diagram

16. Setup Acknowledgement Diagram

17. Source to Destination Data Transfer Diagram

18. All packets belonging to the same source and destination travel the same path. Data follows a particular dedicated path, packets reach in order to the destination . All the packets will definitely reach to the Destination. No packet will discard due to unavailability of resources. Efficiency

19. Delay The Total Delay = 3T + 3 + setup delay + teardown delay  

20. Datagram Network Routing Table Efficiency Delay Virtual Circuit Network Addressing Global Addressing Virtual Circuit Identifier Three Phases Setup Phase Data Transfer Phase Teardown Phase Efficiency and Delay Summary

21. Thank You!! Any Questions? Please!