Re: The banding problem, or Pretend You're a Router

From: Roedy Green (look-on_at_mindprod.com.invalid)
Date: 07/25/04 

Date: Sun, 25 Jul 2004 19:47:18 GMT

On Sat, 24 Jul 2004 15:08:56 GMT, Roedy Green
<look-on@mindprod.com.invalid> wrote or quoted :

>A router in IPv6 has packets coming in each labelled with an 128-bit
>destination. The router is directly connected to N other nodes. You
>have a giant table of IP bands/ranges, and which node each range goes
>to.

It might turn out in the long run, ironically that 128 bit IP
switching is actually faster than 32 bit. Why? It would be easier to
keep a 128-bit address space more closely matched to physical
geography. You might actually need fewer entries in a router mapping
table to describe the routing. As IPv4 gets more and more full, the
routing tables explode in complexity dealing with the little
exceptions.

I was happy to read in that ETH paper that there does exist a
reasonably scaleable algorithm for IPv6 lookup.

It quite amazing that the Internet has managed to deal with the growth
with so little problem. Imagine what would happen if the electric or
phone system had to grow that fast.

I further suppose that if worse came to worse, you could use
approximate routing using abbreviated tables on packets with a long
TTL, and accurate routing on ones about to die soon if they don't get
to their destinations. 

-- 
Canadian Mind Products, Roedy Green.
Coaching, problem solving, economical contract programming. 
See http://mindprod.com/jgloss/jgloss.html for The Java Glossary.

Relevant Pages

  • Re: How do I read/interpret a (netstat) routing table ?
    ... I know this routing table is used to direct TCP/IP packets to their destination. ... Assume on local computer 192.168.0.14 a TCP-IP packet is arriving with the destination ... NetMask --> Makes it easier for the Router (layer 3 device, ...
    (microsoft.public.windowsxp.network_web)
  • Re: Problem related with Subnetting
    ... Can a host in 10.0.0.X talk with a host in ... router or gateway machine. ... The way that machines locate each other is that they send out broadcast ... ARP packets asking for information on the destination IP. ...
    (comp.os.linux.networking)
  • Re: Problem related with Subnetting
    ... Can a host in 10.0.0.X talk with a host in ... router or gateway machine. ... The way that machines locate each other is that they send out broadcast ... ARP packets asking for information on the destination IP. ...
    (comp.unix.programmer)
  • Re: router help needed ....urgent
    ... > I have a cisco router 1800 series with a 4 port fast ethernet card. ... Policy-based routing is your only option. ... and even then you are at the mercy of your provider to make it work. ...
    (comp.dcom.sys.cisco)
  • Re: router help needed ....urgent
    ... now what i need is that all my traffic for internet ... >> routing or PBR on cisco, ... If both links are to the same ISP router then you can use BGP ... Why not just put the 2 internet feeds into a hub/switch and connect the router by 1 ethernet port and use IP routing and NAT to determine the best route to use. ...
    (comp.dcom.sys.cisco)