Paul; You state: At 05:47 PM 11/17/95 -0500, Sean Doran wrote:
There are substantial disadvantages, too.
In order to take advantage of the greater port-density(-per-dollar) on FR switches right now, the end user has to use FR, which is not always practical or desirable.
One of the reasons why end users find frame-relay undesireable is that they cannot be assured that their provider is not grossly oversubscribed on PVC-per-port density. When you buy a T1 private line, you can be assured that you're not sharing it with 120 other end-users. :-) DS3/DS1 Backbone/Trunk capacity planning principles, whether across a Frame Relay Backbone or Cisco 7000 hdlc trunk network are still the same. It's just as easy to over configure DS3/DS1 Cisco HDLC trunks as Frame Relay trunks. Potentially at issue here is not Frame Relay networks as a transport but that a Cisco 7000 can not scale properly to support 120+ end-users. :-) Modern Frame Relay switches: 1) have sub-msec latency 2) can support multiple trunks at DS3+ (to include ATM) 3) are not burdened with processing any of the IP layer 3 nor routing overhead 4) because of 3 have a cost per port that is 300 to 400% less than a Cisco 7000 5) can have it's backbone shared across multiple services thereby reducing both capitalization and bandwidth expense 6) allow ISP to pass the cost savings on to customers ----------------------------------------------------------------------------- Jeff Oliveto | Phone: +1.703.760.1764 Sr.Mgr Opns Technical Services | Fax: +1.703.760.3321 Cable & Wireless, Inc | Email: joliveto@cwi.net 1919 Gallows Road | URL: http://www.cwi.net/ Vienna, VA 22182 | NOC: +1.800.486.9999 -----------------------------------------------------------------------------