Subject: Re: connection bonding?
To: Steven M. Bellovin <>
From: None <>
List: tech-net
Date: 12/07/2005 20:34:05
In message <>,
"Steven M. Bellovin" writes:

>>>In message <200512072235.RAA20918@Sparkle.Rodents.Montreal.QC.CA>, der Mouse 
>>>>One of the most bothersome things about agr(4), to me, is that which
>>>>link a packet goes out seems to depend on nothing but a hash of
>>>>assorted data related to the packet.  This means that if links of
>>>>different speeds are aggregated, the slower one(s) will get overloaded.
>>>>I'd expect it to simply pick the interface with the shortest output

>>[.. discussion of TCP reordering and vendors who got it wrong ...]
>>Hi Steve,
>>In fact, it's more than a feature, it's a _requirement_.
>>IEEE 802.3ad requires that all packets (frames, in layer2-speak) in a
>>flow not be reordered (or htat they traverse the same path through a
>>link-aggreation group, I forget the exact wording, but the intent is
>>unmistakably clear. At least to anyone with our shared backgorund).
>Yup -- it's a requirement precisely because of the problems I outlined. 
>I was speaking more poetically when I phrased it as a I did.

hi Steve,

Sure, I could tell you knew (and would have guessed if I didnt'). I
just wanted to be crystal-clear to der Mouse. I should've addressed
Mouse and cc'ed you; sorry abou thtat.

For the record, IEEE ad the 2004/2005 edition of 802.3 downloadable at
no charge, thanks to corporate sponsorship (in sharp contrast to
normal IEEE policy, which is one big reason I'm not an IEEE member.)