Triple play in Tier 1 carriers

[jingshao () teekoo com]

Hi,

My friend is constructing an ISP that provide data, video 
and voice services. He wanted to know a little bit 
information on how do the big ones such as ATT, Verizon, 
Sprint, Comcast design their infrastructures to support 
Voice and Video.

Any pointer will be very appreciated.

Thanks,
Jingshao