exercise with ip phones and Qos in MPLS/VPN

pepsodent

Hy guys,

I need to find a solution for this exercise.

1. You are the CSE and you are meeting with a customer that has a technical problem. Your customer has a central site with Call-manager, IP phones and 4 remote sites.
2. Each site connects to an MPLS/VPN via frame-relay between PE and CE. At the remote sites there are also IP phones. Each site has a 2M pipe towards the MPLS/VPN cloud. Every site (CE) has QOS configured.

Problem:
- The customer complains about intermittent bad voice quality
- Help solve the customer’s problem.


Thanks!!:)

wallpaper_01

I'm probably not far along enough in my studies yet to know but you could try using a different codec. If its intermittent it would be a bandwidth problem. Look at the table below and you can see G.729 has a low bandwidth. You need to make sure that the phones support the codec though. G.729 is good used on WAN links.

http://www.voip-sip.org/wp-content/uploads/2011/06/codec_payload_bandwidth_consumption.gif

Global Knowledge Training Blog » Cisco IP Phone Audio Codecs

That's as far as my knowledge goes so far, not sure about QOS yet but obviously you will want to prioritise voice.

Anyone else feel free to add, as I would be interested to know the answer too