BGP attribute 128 activity

Has anyone else been observing this? This appears to be ATTR_SET and is appearing at route-views.

Was curious if anyone else was tracking this (or the origin ;)).

It's been going on for some time now and it's not seemed to cause any troubles (part of the reason i monitor for these attributes, early telemetry of attribute noise that has caused vendors trouble..).

- Jared

-- snip --
00 00 FD 88 40 01 01 02 40 02 00 40 05 04 00 00
00 64

Hi , first sorry for lame question but i'm new to BGP.
In my ISP I have two full BGP sessions with my two transit providers (X
and Y), and for every provider i have assigned PA (Provider
Aggregatable) networks. Is it possible (if there are no filters on other
side) to advertise X networks to Y and Y to accept them ? My confusion
comes from the PA status , i know if it is PI there are no problem to
route it to any AS.

Basically I think you need to check with your providers whether they
will accept each other PA's

Generally speaking, you need at least a /24 from one or the other of
them, you need a letter of authorization (LOA) from the one that
provided the /24 permitting you to announce it to other ISP(s) and
you'll need to test to make sure the ISP who assigned the /24 has set
up their filters properly so that you can communicate with them over
the Internet even when your line to them is down.

For your first foray in to BGP, I strongly advise you to contract an
expert for help both programming your router and interacting with your

Bill Herrin

If it's SWIP'd to you by your provider, it is yours to use, and most providers will accept it. The difference between them is paperwork; that's all.


Our organization does exactly this. The requirements we have run into are:

1. The block needs to be at least a /24 and registered with SWIP
2. You will need LOAs from the owner of the block. This used to take months to get, now it seems the isps have streamlined this operation
3. You cannot trust the second isp to advertise the SWIP block correctly if they are not a tier 1. Even though they may advertise it for you to their upstream, they don't always have the appropriate procedures in place to get the LOAs to the upstream so your block just gets filtered out.

Dylan Ebner

Just got done battling this exact issue with one of our upstream peers...caused a lot of headaches for us.

Proper registration in a routing registry helps, too.

"George Bonser" <> writes: