Network Performance Models

There are performance metrics that we talk about in relation to networks. Here they are.

Link rate

Refers to the maximum number of bits that can be push through a link per unit time.

Throughput

Refers to the number of bits that a link can push from sender to receiver. (unlike link rate the this is a measure that describes end-to-end transmission)

End-to-end delay

sum of processing, queuing, transmission, propagation delay.

1. processing delay: time it takes to package/unpackage bit
2. queuing delay: time taken as a package waits (in a buffer) to be transmitted
3. transmission delay: time taken to transmit a packet from across a link (affected by bandwidth)
4. propagation delay: time it takes for a packet to go from one end to the other (affected by distance of the link)

Response time

Similar to end-to-end time (same units). But it is approximately twice that of end-to-end time. Also known as round trip time