[OT] aal5 pdu CRC

Jose M Rodriguez josemi at freebsd.jazztel.es
Thu Jan 27 07:00:34 PST 2005


Hi,

get some free time to work in uadsl, but have a problem.  Hope someone that 
can read ITU I.363 can answer this.

Every usb adsl modem implementation I see doesn't obey aal5 pdu encoding 
standards, which requires that the PDU trailer come at the begin of a fresh 
cell.

So, I think that the modem must rework this and generate two cells on the 
wire.  Due how this modems works, I doubt that the modem recalculate PDU CRC 
itself, So...

Can someone confir if the CRC covers the PAD?  I'm begin to think that the CRC 
only covers the playload and the pdu-trailer.

--
  josemi


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