"Is TDM going the way of dial-up?"

Kevin Oberman oberman at es.net
Tue Mar 30 00:14:29 CDT 2010

> Date: Fri, 26 Mar 2010 16:43:23 GMT
> From: msokolov at ivan.Harhan.ORG (Michael Sokolov)
> Rick Ernst <nanog at shreddedmail.com> wrote:
> > I've noticed over the last 3 years or so that TDM, specifically T-1, access
> > and transport has been in a steady decline.  Customers are moving to FTTH
> > and cable, or going WiMAX and Metro-Ethernet.  Ethernet seems to have taken
> > an even bigger bite out of DS-3.  The bigger pipes seem to favor ethernet. A
> > recent upgrade from OC-3 to GigE transport actually saved us a large chunk
> > of money.
> >
> > I'm wondering if others are seeing the same behavior, if it's
> > market-dependant, or if I'm just imagining things.
> Unfortunately what you are seeing is indeed where the world is going,
> and it is extremely painful to watch.  My personal preference is the
> direct opposite of that: Ethernet for non-LAN use is my very antithesis,
> I hate it to the core of my being.  V.35/HDLC forever for me!  I will
> continue using HDLC over traditional synchronous serial WAN media for as
> long as I am alive.
> MS
> P.S. This message is being sent from a VAX running a variant of 4.3BSD
> (Quasijarus).  Almost the entire ARPA Internet software stack that's
> running on my VAXen is mostly unchanged from how it was in 1988.

Much as I love Sonet and the like, I will channel Randy and say that I
hope all of my competitors do this.  (OK. We really don't have

And, if you are using a 1988 TCP stack on a 4.3 system, you are not
likely to ever efficiently utilize a higher speed link and will not
behave well on any link. TCP has come a long way in the past 12
years. (Of course, I can't guess what "mostly unchanged" means.)
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman at es.net			Phone: +1 510 486-8634
Key fingerprint:059B 2DDF 031C 9BA3 14A4  EADA 927D EBB3 987B 3751

More information about the NANOG mailing list