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What type of QoS to be used for video conferencing and data on same T1?

In this scenario there is a T-1 between a 3660 and a 2611 that all data and video conferencing travel across. There are video conferencing problems if a large data file is being transmitted. What is the best QoS method for this.

  • Other Collaboration Voice and Video Subjects

Re: What type of QoS to be used for video conferencing and data

Video , Audio or Voice are constant stream of rtp packet and same QOS applies. The best way to gois to clasify all udp rtp packet in the real-tine application prt rangeand pre-allocate a certain amount of bandwidth to the video traffic.

Claculation of bandwidth used by codec :

[Codec Bandwidht used for video _ (1+ overhead/payload-size)] + additional 5 KB saftey margin.

interface serial 0/0:23

ip address

encapsulation ppp

ppp multilink

ppp multilink interleave

ppp multilink fragement-delay 10

ip rtp priority ip rtp priority 655535 16383 960


The above would queue any rtp packet ranging from video, voice or audion in a high PQ which will be dequeued (emptied) first before going to service data waiting

in the WFQ.

It is necessary to calculate the bandwidth require for one video confrecing session and multiply by x for the bandwidht reservation. x is the number of session that will be carried over the T1 link.

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