Lectures notes for 2010 - KTH

QoS & Scheduling algorithms
Predictable delay is thought to be required for interactive real-time applications:
Alternatives:
1.use a network which guarantees fixed delays
2.use a packet scheduling algorithm
3.retime traffic at destination
Since queueing at routers, hosts, etc. has traditionally been simply FIFO; which
does not provide guaranteed end-to-end delay both the 2nd and 3rd method use
alternative algorithms to maintain a predictable delay.
Algorithms such as: Weighted Fair Queueing (WFQ)
These algorithms normally emulate a fluid flow model.
As it is very hard to provide fixed delays in a network, hence we will examine the
2nd and 3rd methods.
Maguire QoS & Scheduling algorithms 8: 63 of 78
maguire@kth.se 2010.03.21 Internetworking/Internetteknik