InfiniBand Network Architecture

SQ Logic Operation

Start PSN Assignment and PSN Management

As with any of the other transport service types, the SQ Logic's Start PSN is assigned during QP setup.

As the SQ Logic generates each outbound request packet, it sets the BTH:PSN to the previous PSN + 1.

Q_Key in Outbound Request Packet

When the request packet is transmitted by the QP's SQ Logic, the Q_Key inserted in the packet's DETH:Q_Key field is one of the following:

• If bit 31 of the 32-bit Q_Key submitted in the WR = 0, then it is the Q_Key of the destination QP and is inserted in the packet's DETH:Q_Key field.

• If bit 31 of the 32-bit Q_Key submitted in the WR = 1, then the software that posted the WR is attempting to access a controlled destination QP and the Q_Key from the local ...