Error detection, Packet length, 29 error detection – Teledyne LeCroy IBTrainer - IBTrainer Users Manual User Manual
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Testing Capabilities of the IBTrainer
Overview of the IBTrainer
CATC IBTrainer InfiniBand Exerciser, August 2002
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Error Detection
The IBTrainer calculates the ICRC (Invariant CRC) and the VCRC
(Variant CRC) automatically. You can influence this by making one of the
following choices:
•
Τhe behavior ‘bad packet’ causes the IBTrainer to end the packet with
a bad packet delimiter (EBP).
• The behavior ‘bad ICRC’ corrupts the ICRC.
• The behavior ‘bad VCRC’ corrupts the VCRC.
To corrupt a packet, the IBTrainer places the 1’s complement of the
appropriate CRC calculated for the transmitted packet in the CRC field.
Packet Length
The IBTrainer distinguishes between the real packet length and the
shown packet length. The real packet length is purely an internally used
value, which can, but does not have to, correlate with the packet length
shown in the packet header. You can create an illegal packet length by
setting the shown length to a value that is at variance with the real packet
length. You can set this behavior on a per-packet basis.