[nsp] atm encapsulation overhead

Dan Hollis goemon at anime.net
Tue Nov 18 17:32:32 EST 2003


On Tue, 18 Nov 2003, Gert Doering wrote:
> On Tue, Nov 18, 2003 at 10:03:00AM +0100, Iva Cabric wrote:
> > > calculate it. they only deal with calculating and showing aal5snap.
> > Difference between aal5mux and aal5snap is 8 bytes (LLC/SNAP). So Table
> > 6, in PS document, states this:
> > LLC/SNAP			1.37%
> Unfortunately, that's not all of it.  With aal5mux, a TCP ACK packet with
> no data fits into *one* ATM cell, with aal5snap, you will always need two.
> So for typical web traffic (data going one way, pure ACKs in the other
> direction), aal5snap overhead is significantly higher.
> I don't have numbers, though.

Since nobody seems to have actual data, I set up a lab and now have real 
numbers for aal5mux ip vs aal5snap for mtu 1500.

-Dan
-- 
[-] Omae no subete no kichi wa ore no mono da. [-]



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