fractional gigabit ethernet links?

Peter John Hill peterjhill at cmu.edu
Tue Jul 16 15:59:19 UTC 2002


It is very messy, but until we get a Supervisor/MSFC/PFC that can police on 
egress vlan...

We have two bgp sessions with our provider, one that distributes I2 routes, 
and the other, default. Each points to the other end of their respective 
/30 subnets on their own vlan on an 802.1q trunk (set up manually, not 
using VTP.

This box is connected to two separate layer 2 cores via two /29s (via 
802.1q trunks). Once /29 is the "Commodity" (ie. we must pay) vlan, and has 
the default-information-originate. Then, the other /29 has its own ospf 
process (like i said, messy). We redistribute the bgp I2 routes into that 
ospf process, using as-path filters.  Now at the two cores, when traffic 
for the commodity traffic comes in, it goes to the border router via one 
vlan, research/I2 traffic the other. We are then able to filter on the 
ingress vlan on the border router.

Now, for you, if don't have a situation where some of your external traffic 
needs rate-limited, while some can flow as fast and free as it wants, then 
you just need to do in-bound rate limiting, coming from your internal 
network to your border router.

What sucks for us, is that since we are not experiencing any congestion on 
our internal network, we can't take advantage of wfq or wred.

That was as simple as i could put it, if you have other questions, please 
ask.

--On Tuesday, July 16, 2002 11:41 AM -0400 Alex Rubenstein <alex at nac.net> 
wrote:

>
>> Is this link in production? We are using a gigabit ethernet to our
>> provider. We are limited on our traffic going to Commodity traffic, but
>> have free reign on our Internet 2 traffic. We found that we get the best
>> results when we shape/police our traffic to stay within our contractual
>> limits, on our side of the link. Since we are using a 6509 with a Sup1A,
>> we had to do some tricky things to police traffic on only one vlan of an
>> 802.1q trunk on the gigE connection. It works though. We see
>> insignificant losses on the link.
>
> can you share how you are doing this?
>
> Hybrid or integrated?
>
>
>
>>
>> good luck!
>>
>> Peter Hill
>> Network Engineer
>> Carnegie Mellon University
>>
>
> -- Alex Rubenstein, AR97, K2AHR, alex at nac.net, latency, Al Reuben --
> --    Net Access Corporation, 800-NET-ME-36, http://www.nac.net   --
>
>
>





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