[BBLISA] Telecommunications Recommendations...

[Robert Keyes]

On Wed, 14 Jul 2010, Bill Bogstad wrote:

>
> While the above is technically correct, in his circumstance BGP is not
> an option.   To do BGP you TYPICALLY need to
> own your IP address space in order to be able to advertise them
> successfully.  He's talking about how many addresses his provider is
> going to give him so he doesn't have such addresses.

Not really. You can get a chunk of IP space from your main provider, and 
advertise a route to it through your backup provider. This is becoming 
more common as IPv4 space is becoming a more expensive commodity.

> Second, the address space he's talking about is so small that even if
> he does get addresses and providers who will do BGP, no one else will
> pay attention to his advertisements anyway.

Yes, this is true, you generally need a /24 (a.k.a. class C, 255 IP 
addresses) in order to be sure your route is propagated across the whole 
net. But I am a bit unusure of this, there may be ways around this 
problem.

> Each advertisement takes
> up expensive memory in core Internet routers and the larger network
> providers aren't going to spend lots of money so he can have redundant
> network providers.  Don't go there.

Well yes it does take up more memory, but that doesn't mean the route 
won't propagate through BGP. I still regularly get route announcements for 
very small allocations (as small as a single host!), and people won't 
announce or propagate such routes if they didn't have value.

For those that care, I have a colocated server running BGP with a single 
upstream. The reason for this is to announce routes as I see fit, and then 
tunnel them back to where I want.


But anyhow, this is getting way off topic.