[15844] in North American Network Operators' Group
Re: IP over SONET considered harmful?
daemon@ATHENA.MIT.EDU (John G. Scudder)
Mon Mar 23 16:09:27 1998
In-Reply-To: <008001bd5453$b5dcb100$48d82299@kentdesktop>
Date: Fri, 20 Mar 1998 18:42:55 -0500
To: "Kent W. England" <kwe@geo.net>
From: "John G. Scudder" <jgs@ieng.com>
Cc: "Alan Hannan" <alan@globalcenter.net>, "Yakov Rekhter" <yakov@cisco.com>,
<nanog@merit.edu>
At 2:57 PM -0800 3/20/98, Kent W. England wrote:
>As I recall, the world didn't end when the NSFNET NSSs were installed and
>they decremented TTL twice. Weren't they changed to decrement once,
>appearing as one instead of two routers?
You got this part right. I thought we had heard the last of the TTL
whining then. Apparently we haven't made much progress in the last eight
years.
>(For those who don't remember the NSFNET "routers" they consisted of an IBM
>RS6000 attached to each of several T1/T3 interfaces, interconnected across a
>FDDI with a route server. Nine RS6000s in all. 200 amp service required. :-)
But this part is wrong. The description above is kind of a combination of
the T1 NSS (rack of RTs, each RT services at most a single T1 or Ethernet,
they talk to a route processor) and the T3 NSS (RS/6000 with autonomous
port cards, pretty similar to any modern router).
There's a half-decent description of the NSS architecture at
http://www.merit.edu/nsfnet/
Historically yours,
--John
--
John Scudder email: jgs@ieng.com
Internet Engineering Group, LLC phone: (734) 213-4939 x14
122 S. Main, Suite 280 fax: (734) 669-8661
Ann Arbor, MI 48104 www: http://www.ieng.com
