• The partner LU can negotiate the BIND and send back a positive response that indicates that it supports only single sessions. (It changes the parallel-session support bit and the CNOS support bit 6 and 7 in byte 24 of the BIND response.) In this case, VTAM deactivates the SNASVCMG session and marks the session partner as single-session capable.
• The partner LU can reject the BIND, sending a negative BIND response or UNBIND with a sense code of X'0835'xxxx, where xxxx can be either the offset of the first character of the SNASVCMG mode name or X'0018' (the offset in the BIND of the byte containing the indication of parallel-session support). When this occurs, VTAM concludes that the partner is single-session capable.

If VTAM receives a session-initiation request from the partner LU, VTAM determines from the BIND whether the partner is single- or parallel-session capable.