Wireless IP Telephony

[yzakhem1001]

Dear all,

we have a customer who is planning to use IP telephony over Wireless,

the wireless system will be dedicated for IP telephony (no data will be used over it) and will be Point-to-Multipoint ( the call manager will be in head office which is connected via wireless to the remote branches( some of them are located at 1000 m and others at 10 Km away) where the IP phones will be used and note please some sites will be used as repeater or relay for other sites in the same campus .

the questions are : is it possible use IP telephony in a similar wireless environment( point to multipoint )over such distances ? if yes waht is the best cisco wireless product that will adopt to IP telephony ?

Thanks and reagrds,

Yaacoub

[mheusinger]

Hello,

for acceptable VoIP quality, according to ITU G.114 you should have:

- less than 150 ms one way delay

- less than 30 ms jitter

- less than 0.5% packet loss.

This can or can not work in a wireless environment.

In your case one way delay should not be an issue.

The issues are, that you might have packet loss problems because of bad link quality (caused by interference, bad antenna design, etc.) or too much traffic, etc.

A starting point in your hardware decision process can be "Cisco IOS Software Configuration Guide for Cisco Aironet Access Points" and the chapter "Configuring QoS" at

http://www.cisco.com/en/US/products/hw/wireless/ps4570/products_configuration_guide_chapter09186a0080184a9d.html

Hope this helps! Please rate all posts.

Regards, Martin