DSL for Cisco IPT

[abbas.ali]

Is there any issues with running Cisco IP Telephony over a DSL connectivity. One of the customer's site has a DSL connection to IP/WAN, and I was wondering if IP Phones will be reliable over that link communicating with Ciso Call Manager at the Head Site.

[Tommer Catlin]

It's a broadband connection, so you are at the mercer of the provider for quality of service. If the DSL slows down, there is no way a voice connection can keep a decent MOS score.

But if you are only running a couple phones, back to CCM via a IPSEC tunnel, it will work. Just don't drag or download 1gig files off the web or from HQ. Your firewalls may be able to prioritize the packets, but once they are in the DSL net, there is no guarentee the voice will stay.

also, think about 911 and what you need for requirements. If this remote dials 911, is there some kind of routing for this or?

[espereir]

If you have a VPN tunnel you just need to worry about the routing between the client and the HQ, but if you are planning to send the voice stream over the internet, please make sure to have CTL, this mechanism will encrypt all the IPC traffic towards to CCM.

[espereir]

By the way, you should use G729 instead of G711, that way you will save some bandwidth.