David, at 22:04 on Jun 14 1996, you wrote to Paul Edwards...

PE> SREJ is?

db> Selective Reject in MNP blocks, so that only faulty blocks are resent 
db> rather than stopping transmission and restarting at the faulty block (plus 
db> all subsequent, possibly perfectly fine, blocks).

Not too bad Dave, although it also applies equally to LAPM connects.  

Here's the definitive word from USR themselves...

------------------------------------------------------------------
Selective Reject

In the past, if an error occurred during the reception of a series 
of data frames, the entiire series was resent.  Selective reject 
allows your modem to request that only the faulty frame be resent.
This reduces the number of retransmitted frames, improving overall 
throughput, especially over noisy lines.
------------------------------------------------------------------

Regards, Bill
@EOT:

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