nanog mailing list archives
Re: Scalability issues in the Internet routing system
From: Lincoln Dale <ltd () interlink com au>
Date: Wed, 26 Oct 2005 19:42:51 +1000
Alexei Roudnev wrote:
You do not need to forward 100% packets on line card rate; forwarding 95% packets on card rate and have other processing (with possible delays) thru central CPU can work good enough..
heh.in the words of Randy, "i encourage my competitors to build a router this way".
reality is that any "big, fast" router is forwarding in hardware - typically an ASIC or some form of programmable processor. the lines here are getting blurry again .. Moore's Law means that packet-forwarding can pretty much be back "in software" in something which almost resembles a general-purpose processor - or maybe more than a few of them working in parallel (ref: <http://www-03.ibm.com/chips/news/2004/0609_cisco.html>).
if you've built something to be 'big' and 'fast' its likely that you're also forwarding in some kind of 'distributed' manner (as opposed to 'centralized').
as such - if you're building forwarding hardware capable of (say) 25M PPS and line-rate is 30M PPS, it generally isn't that much of a jump to build it for 30M PPS instead.
i don't disagree that interfaces / backbones / networks are getting faster - but i don't think its yet a case of "Moore's law" becoming a problem - all that happens is one architects a system far more modular than before - e.g. ingress forwarding separate from egress forwarding.
likewise, "FIB table growth" isn't yet a problem either - generally that just means "put in more SRAM" or "put in more TCAM space".
IPv6 may change the equations around .. but we'll see .. cheers, lincoln.
Current thread:
- Re: Scalability issues in the Internet routing system, (continued)
- Re: Scalability issues in the Internet routing system Andre Oppermann (Oct 18)
- Re: Scalability issues in the Internet routing system Tony Li (Oct 19)
- Re: Scalability issues in the Internet routing system Alexei Roudnev (Oct 23)
- Re: Scalability issues in the Internet routing system Tony Li (Oct 24)
- Re: Scalability issues in the Internet routing system Blaine Christian (Oct 24)
- Re: Scalability issues in the Internet routing system Christopher L. Morrow (Oct 25)
- Re: Scalability issues in the Internet routing system Valdis . Kletnieks (Oct 25)
- Re: Scalability issues in the Internet routing system Christopher L. Morrow (Oct 25)
- Re: Scalability issues in the Internet routing system Rubens Kuhl Jr. (Oct 25)
- Re: Scalability issues in the Internet routing system Alexei Roudnev (Oct 25)
- Re: Scalability issues in the Internet routing system Lincoln Dale (Oct 26)
- Re: Scalability issues in the Internet routing system Rubens Kuhl Jr. (Oct 26)
- Re: Scalability issues in the Internet routing system James (Oct 26)
- Re: Scalability issues in the Internet routing system Rubens Kuhl Jr. (Oct 26)
- Re: Scalability issues in the Internet routing system sthaug (Oct 26)
- Re: Scalability issues in the Internet routing system Elmar K. Bins (Oct 27)
- Re: Scalability issues in the Internet routing system sthaug (Oct 27)
- Re: Scalability issues in the Internet routing system JORDI PALET MARTINEZ (Oct 26)
- Re: Scalability issues in the Internet routing system Alexei Roudnev (Oct 26)
- Re: Scalability issues in the Internet routing system Valdis . Kletnieks (Oct 26)
- Re: Scalability issues in the Internet routing system Blaine Christian (Oct 26)