Frame-Relay vs. ATM?

Hello everyone,

  I apologize for putting this out to everyone, but I don't know the
answer to this question and I feel it's best to go to the source.

  My company is forcing me to do a Frame vs. ATM cost-benefit
comparison. The Frame-Relay connection would be PVC's connecting 3 sites,
Chicago, West-Coast, East-cost (offices). I am attempting to do
video-on-demand, voice-over-IP, and data over these pipes, and would like to
ability to do Internet+private LAN connecting all 3 sites for file-sharing,
email sharing, etc without having to do VPN over the Internet.

  My question? What is the benefit of Frame-Relay from say, Sprint or
AT&T versus an ATM connection for all 3 sites from Savvis or Broadwing? I'm
trying to find the technical details and merits behind both these
methods/technologies. Any replies would be appreciated off-list, and I will
send a aggregate report to anyone interested.

  Thank you much everyone for answers in advance,

Ralph M. Los
Asst. Vice-President, Internet Systems and Security
EnvestNet Advisory Corp.
(312) 827-3945 (direct)
(312) 296-9003 (wireless w/voicemail)