[Nottingham] Hosting your own domain/s?

Robert Davies nottingham at mailman.lug.org.uk
Tue Jul 8 13:38:00 2003


On Tuesday 08 Jul 2003 13:01, Alex Tibbles wrote:
> Routing is a hard problem (NP complete, I guess -
> please correct if I'm wrong) so having routers that
> route _really well_ (like not going via TeleHouse etc.
> for local traffic) would require very powerful
> routers. I suspect that the reason this isn't the case
> is that wasting bandwidth is (much) cheaper than
> having supercomputers for routers.

I actually think it's because communication hubs are naturally efficient.  See 
to get well connected to network, it is essential to have a good pipe (and a 
backup for it) to 2 major access points.

Now when you have the money to spend on upgrades, due you do it, by 
commissioning a local link that's fairly small between geographically close 
cities?  Or do you tend to pay the (probably) lower cost of widening the high 
capacity pipes you already have?  The second solution benefits all your 
customers, whilst the first leads to a profusion of relatively low bandwidth 
connections being leased, which offer lower peak capacity and may suffer from 
patchy utilisation, you also most likely have a headache of obtaining revenue 
for through traffic that you carry, and if you don't then the rest of the net 
does not benefit.

To make network meshes really effective, you probably have to completely 
rethink network routing, and make it more like how cars are navigated.  
Rather than a router, deciding in a deterministic fashion to use the 
'optimal' route, something much more fuzzy would be needed to allow packets 
to be passed along a number of feasible alternatives (note at each stage, 
back tracking would need to be prevented).  Now can you imagine the 
complexity and knowledge of the link states of all the possibilities?  The 
risks of routing loops would be very high, and the non-deterministic nature 
and sheer complexity would make network troubleshooting and management a 
nightmare.

Anyway IPv6 (remember that) is meant to aid and simplify, attempts at 
geoghraphically 'sensible' routing by the use of country prefixes etc.

Rob