Quality of service computer network

Bsc it second year computer network

1. Computer Network Topic : Quality Of Service & Ineternetworking Presented By Pratiksha srivastava

2. CONTEXT Definition Parameters Flow characteristics Technique to improve Resource Reservation Application

3. Quality of service The ability of the network to provide better or special service to set of dataflow to the detriment of other dataflow”

4. QoS Parameters Flow data transfer Transit time when transferring data Residual error rate Probability of failure of the network connection Release time the network connection

5. Reliability : Is a characteristic that a flowneeds in order to deliver the packetssafe and sound Delay : Different application can tolerate delay in different degrees Jitter : jitter is the variation in packet belonging to same flow Bandwidth : different application need different B/W

6. Techniques to improve the quality of service Scheduling FIFO (First-in-First-Out) QUEUING PRIORITY QUEUING WEIGHTED FAIR QUEUING Traffic Shaping LEAKY BUCKET TOKEN BUCKET Resource reservation Admission control

7. Scheduling Packet from different flow arrive at switch or router for processing A good scheduling technique treats the different flow in a fair and Appropriate manner

8. FIFO (First-in-First-Out) QUEUING Full? processor Departure Discard Arrival N Y Queue Packet wait a buffer (queue) until the node is ready to process them. If avg. arrival rate>avg. processing rate => new packet will be discarded.

9. Resource reservation A flow of data needs resources such as buffer , bandwidth CPU time and so on QoS can be improved if these resources are reserved beforehand

10. Application Mobile communication Real-time video and sound Transmission Interactive applications on network Routing for traffic with performance guarantees QoS -aware ATM application

11. Topic to be covered: INTRODUCTION REQIREMENTS OF INTERNETWORKING DEVICES USED FOR INTERNETWORKING COMPONENTS OF INTERNETWORKING

12. Internetworking is the process or technique of connecting different network by using intermediary devices such as router or gateway device The standard reference model for internetworking is open systems interconnection (OSI) Any interconnection among or between public private commercial industrial Or government computer networks may also be defined as an internetwork or internetworking