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Re: Comments on draft-van-beijnum-multi6-isp-int-aggr-00.txt

What first strikes me is the complexity of the iBGP and keeping this up
to date.


I am not convinced that this is workable from a ISP point of view,




I agree that it's a hassle, but it's not all that complex. It is

basically similar to running OSPF with area aggregation. Larger ISPs

already have complex BGP setups with route reflectors and/or

confederations and redistribution. This proposal is on the same level 
of

complexity.



What do you mean by keeping it up to date?



Well, ISPs and large enterprises normally use some form of policy 
routing, even if it being hot-potato. With this, I would most likely 
need to maintain my iBGP to send traffic to the "right" prefix, via the 
right exit. Especially if I span several areas. Today this is per peer 
which is somewhat simpler.




but
I want to think that over more. I am also not sure how "extras" in BGP
(which I am not sure should be there in the first place) such as
multicast and VPN information, would work.



Multicast uses a separate routing table so there shouldn't be any
impact. VPN is not a part of regular BGP.




True, but it is still in use. As for multicast you still need to find 
the next-hop information for PIM you need to do the RPF.




Another problem I see is that this requires networks that logically 
map

fairly well into the physical topology, or even small networks gets

complicated.



Small networks are unlikely to use internal aggregation: it's more

likely they'll just send traffic for certain regions (where they are 
not

present themselves) to their upstream ISPs.


Yes, but what if I cover several regions? I.e I am not a small network?




This means that the MPLS crowd will have a problem (hey -

maybe I do like this proposal! :) ), but so will also corporations 
that

have few branch offices across the world connected with a IP-VPN or

slow speed links.



I'm not sure what kind of problem you see here. I am unfamiliar with 
the

way MPLS is really deployed in networks so I can't say anything about

that except that if the worst part about this protocol is that it makes

it impossible to provide integrated IP and MPLS services I can live

with that: just de-integrate them.



Agreed. From what I know many people have deployed more or less full 
meshed networks with MPLS.






Last, what worries me the most is the security considerations. A
failure on filtering, or in routing configuration will make the AS7777
incident seem like trivial.



No.



Uhm, why not?






This is not even in the security considerations section. It should be.



No.




Why not?

- kurtis -