18 - QOS Flashcards
QOS Tools give you a means to manage what 4 characteristics ?
- Bandwidth
- Delay
- Jitter
- Loss
What is bandwidth as it relates to QOS?
Capacity of the link.
What is delay?
- 2 types of delay
- One-way Delay - the time between sending a packet and that same packet arriving at the destination host.
- Round-trip Delay - the time it takes to send a packet and receive one back
What is jitter?
A variation in one-way delay between consecutive packets sent by the same application.
What is loss?
The amount of lost packets usually as a percentage of the total packets sent.
What are the guidelines for Interactive Voice?
- Delay - 150 ms or less
- Jitter - 30 ms or less
- Loss - 1% or less
What are the guidelines for Video?
- Bandwidth - 384 kbps to 20+ Mbps
- Delay - 200 to 400 ms
- Jitter - 30 to 50 ms
- Loss - .1% to 1%
What is Classification and Marking?
Marking of packets and the definition of trust boundaries
What is another name for Congestion Management?
Queuing
What is Congestion Management?
The scheduling of packets to give one type of packet priority over another.
What is Congestion Avoidance?
Addresses how to manage the packet loss that occurs when network devices get too busy.
What is NBAR?
Network Based Application Recognition
What do IP Phones mark voice payload packets with?
EF
What do Cisco IP Phones mark call setup packets with?
CS3
In an X-Y chart which is on the horizontal axis?
X which is the Best Drop to Worst Drop priority