nanog mailing list archives

Flow Based Routing/Switching (Was: "Does TCP Need an Overhaul?" (internetevolution, via slashdot))


From: Jeroen Massar <jeroen () unfix org>
Date: Sat, 05 Apr 2008 12:16:01 +0200

Paul Vixie wrote:
[..]
i wouldn't want to get in an argument with somebody who was smart and savvy
enough to invent packet switching during the year i entered kindergarden,
but, somebody told me once that keeping information on every flow was *not*
"inexpensive."  should somebody tell dr. roberts?

Isn't the reason that "NetFlow" (or v10 which is the the IETF/Cisco named IPFIX) exists the side-effect of having routers doing "flow based routing" aka "keeping an entry per IP flow, thus using that entry for every next packet to quickly select the outgoing interface instead of having to go through all the prefixes" ? The flows are in those boxes, but only for stats purposes exported with NetFlow/IPFIX/sFlow/etc. Apparently it was not as fast as they liked it to be and there where other issues. Thus what exactly is new here in his boxes that has not been tried and failed before?

Greets,
 Jeroen

Attachment: signature.asc
Description: OpenPGP digital signature


Current thread: