An example of a Telnet session in CICS

Figure 1 shows a CICS® system that is using a Telnet session to enable communications between the client machine and the server machine.
Figure 1. An example of a Telnet session in CICS
An example of a Telnet session in CICS
  1. Area 1 in Figure 1 shows the two methods that can be used to initiate a Telnet session. The inetd daemon can be run. In addition, the cicsteld command can be issued from the command line. Both these methods start the cicsteld process on the server from within their programs. The inetd daemon is configured by using the cicscp create telnet_server command. See Configuring the inetd daemon using the cicscp command.
  2. Area 2 shows a cicsteld process that is started on the server when the cicsteld command is issued. This process listens at a specified port for any client requests.
  3. When the cicsteld process receives a client request, a connection is made to the region. This is shown in Area 3.
  4. When a region receives a connection request from a client that is using the Telnet server process, the region issues a terminal autoinstall request. This is shown in Area 4. When the terminal is installed, a CICS session can be started, and CICS commands can be issued.
Note: When the cicsteld server process receives an automatic transaction initiation (ATI) transaction, the keyboard remains locked if an ATI transaction is about to start. When the ATI transaction starts and issues a terminal request such as SEND, the keyboard is unlocked.