gtpc1m0f | Transmission Control Protocol/Internet Protocol |
The 3172 Model 3 Interconnect Controller with the Offload program, or a
similar workstation, is integral to TCP/IP support. The 3172 Model 3
Interconnect Controller is configured as an offload device between the TPF
host and local area networks (LANs).
Figure 5 shows two 3172 Model 3 Interconnect Controllers with the
Offload program defined to a TPF system. The following naming
conventions are used:
- The socket application programming interface (API) support program in the
TPF host has the TPF host application name of TCP/IP. This
name is predefined by the 3172 Model 3. The socket API support program
in the TPF host processor packages the socket API requests and sends them to
the 3172 Model 3 Interconnect Controller for processing.
- The socket offload program in the 3172 Model 3 has the workstation
application (WSA) name of API. This name is predefined by the
3172 Model 3. It processes the socket API requests sent from the TPF
host. When communicating with the TPF host, it uses Common Link Access
to Workstation (CLAW) protocol.
- The symbolic device address (SDA) represents a pair of
subchannels connecting the TPF host processor to the TCP/IP offload
device. The even-numbered subchannels are the read
subchannels, while the odd-numbered subchannels are the write
subchannels.
- If there is only one workstation, the name can be OS2TCP. If there
is more than one workstation the additional names must be OS3172xx
where xx is 2 unique alphabetical characters. In this figure,
the names OS317201 and OS31702 are used.
Figure 5. Two IBM 3172 Model 3 Interconnect Controller Offload Devices Connected to a Host Transaction Processing Facility Processor