gtps2m32 | ACF/SNA Data Communications Reference |
TPF requires the extended network addressing feature available in NCP. This means that the network address contained in a FID4 header is a 1 byte subarea number and 2 byte element address.
As a result, the TPF network address table (NAT) has been expanded to allow for 3 byte network addresses. The Resource Vector Table now treats the RV1NASA field as the subarea and the RV1NA field (which used to be the 2 byte network address) as the element address.
In addition, TPF builds and accepts CDINIT format 3 requests with control vector X'1A', which contains the larger network addresses. TPF indicates this support on the ACTCDRM response to VTAM (bits 9, 12, 13, 16 and 18 of the CDRM usage field in control vector 6 must be set on). CDCINIT format 1 uses session key 15 (network qualified address pair). Session key 15 contains the 6 byte network addresses with the length field set to 12 to indicate no network identifiers.