North American Network Operators Group

Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical

RE: Links on the blink - reprise

  • From: Jeffrey P. Oliveto
  • Date: Sun Nov 19 10:05:34 1995

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:	[email protected]
1919 Gallows Road				|	URL:		http://www.cwi.net/
Vienna, VA  22182				|     NOC:		+1.800.486.9999
-----------------------------------------------------------------------------