On Wed, 2006-06-14 at 10:27 -0400, Phillip Susi wrote: > Jesper Dangaard Brouer wrote: > > The Linux traffic's control engine inaccurately calculates > > transmission times for packets sent over ADSL links. For > > some packet sizes the error rises to over 50%. This occurs > > because ADSL uses ATM as its link layer transport, and ATM > > transmits packets in fixed sized 53 byte cells. > > > > I could have sworn that DSL uses its own framing protocol that is > similar to the frame/superframe structure of HDSL ( T1 ) lines and over > that you can run ATM or ethernet. Or is it typically ethernet -> ATM -> > HDSL?
Nope, not according to the ADSL standards G.992.1 and G.992.2. > In any case, why does the kernel care about the exact time that the IP > packet has been received and reassembled on the headend? I think you have misunderstood what the rate table does... (There is an explaination in the thesis page 57 section 6.1.2) http://www.adsl-optimizer.dk/thesis/ -- Med venlig hilsen / Best regards Jesper Brouer ComX Networks A/S Linux Network developer Cand. Scient Datalog / MSc. Author of http://adsl-optimizer.dk
signature.asc
Description: This is a digitally signed message part