gtpc1m0i | Transmission Control Protocol/Internet Protocol |
TCP/IP builds an interconnection of networks that
provides universal communication services.
The service performed by TCP/IP support is transparent to the application
and is comparable to services performed from other platforms.
An application can be either a client, server, or both, depending on
whether the application requests or provides a service. Program TPF
servers with special consideration to reduce resource usage and to handle
messages most effectively. Figure 7 shows the TPF system as the host with two IBM 3172 Model 3
offload devices.
The following steps correspond to the numbers in Figure 7:
- The TPF host is connected to both token-ring and fiber
distributed data interface (FDDI) networks through the IBM 3172 Model 3
Interconnect Controller with the Offload program, and is able to forward or
receive data from clients on any connected network.
- Parallel or Enterprise Systems Connection (ESCON) channels
connect the TPF host to the IBM 3172 Model 3 Interconnect Controller.
- Each TPF host can connect to more than one IBM 3172 Model 3
Interconnect Controller.
The IBM 3172 Model 3 Interconnect Controller with the Offload program
allows the TPF system to communicate with remote TCP/IP hosts through socket
application program interface (API) functions. See Socket Overview for a detailed description of sockets.
- The 3172 Model 3 Interconnect Controllers send information
packets between local area networks (LANs) and the TPF host
processor. IBM recommends that all 3172 Model 3 Interconnect
Controllers are connected to the same local area network (LAN). The
3172 Model 3 Interconnect Controller can connect to the following LANs:
- Fiber distributed data interface (FDDI)
- Ethernet
- Token-ring.
- Routers distribute information packets of data directly when
the destination and source are on the same TCP/IP network or indirectly when
the destination and source are on two different networks.
- The information packets are routed to the Internet.
Figure 7. Network Overview