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point to point 128 kbps

hi all,

im new to VOIP,i have 2 offices 10 km diff, i would like to implement ip telephones for communication between these 2 equipments are 2801 routers 2 no's and WIC-1T 2 no's point to point 128kbps leased line.maximum 10 users will use ip phone's in this scenario. what all things are required extra other than IP phones.

how can i configure these 2 routers for this scenario.whats the encapsulation for this configuration.pls give me the sample configuration also.

any post will be appreciated with proper rating.

Kind regds



Re: point to point 128 kbps

You will need a switch at each location for the IP phones to connect to the network. Preferably, you would have a switch capable of delivering power to the phones, such as the Catalyst 3560-24PS. You will need either Callmanager or Callmanager Express for call processing. Callmanager Express can run on your 2801 and will support up to 240 phones. Callmanager is a much more scalable product and runs on separate server hardware. Depending on the number of lines at each location you will need a VWIC card in each router to support local dial tone. Examples are the VWIC-1MFT-T1 for PRI and the VIC2-2FXO or VIC2-4FXO for analog lines. You will also need to take bandwidth into consideration. G.711 calls take approximately 80k and G.729 calls take approximately 24k. 2 G.711 calls would take up the entire circuit. If you're going to be running several calls across this link as well as data, you will need to consider increasing the link speed. Also, Callmanager Express has no provision for Call Admission Control. CAC is the ability to limit the number of calls across a given link in order to avoid quality degradation. You will want to employ QoS mechanisms so that voice traffic gets preferential treatment no matter how much bandwidth you have. Take a look at the Qos link below for an overview. The configuration required would get quite lengthy for this post, but the admin guide below will give you a good place to start.


Callmanager Express

Cisco CallManager Express 3.1 System Administrator Guide

QoS Features for Voice Introduction

Hope this helps.