nanog mailing list archives

Re: ATM vs. DS3


From: "William Allen Simpson" <wsimpson () greendragon com>
Date: Thu, 10 Jul 97 16:48:54 GMT

From: Josh Beck <jbeck () connectnet com>
Now, the question is, what is the overhead of the serial (ppp?) protocol
running over the T3? Since it is point to point, and not addressed, it
should be less, or is this not the case?

The framing overhead for PPP over DS3 is about 7 bytes per packet.  You
can make it as few as 4 (PPP header compression) or as long as 10
(32-bit checksum).

I don't know anyone shipping PPP data compression yet at those speeds,
although I've heard of a project using multiple Stac LZS chips.

Anyway, you will get a lot better performance out of a PPP link than an
ATM link; certainly in the short term, and probably in the long term.

WSimpson () UMich edu
    Key fingerprint =  17 40 5E 67 15 6F 31 26  DD 0D B9 9B 6A 15 2C 32
BSimpson () MorningStar com
    Key fingerprint =  2E 07 23 03 C5 62 70 D3  59 B1 4F 5E 1D C2 C1 A2


Current thread: