Using the Application Understanding component
requires communications to be configured at the workstation and at the host. This section describes configuring communications for cooperative sessions between the workstation and the host using APPC (advanced program-to-program communication) protocol.

## Configuring communications for APPC

Configuring APPC cooperative sessions requires coordination between workstation and host administrators.

- Defining the workstation to the network.
- Defining a link from the workstation to the host, or an intermediate APPN node (our examples show the link being defined to the host). The terms link and connection are used interchangeably in this chapter.
- Defining the workstation as a client for APPC sessions.
- Defining the workstation as a server for Remote Debug APPC sessions.

In addition to this configuring, you need to do some SdU configuring.

Configuring the host for APPC requires:

- Defining APPC/MVS Server facilities for cooperative sessions
- Defining VTAM and NCP definitions (if communications are through an NCP)
- Optionally defining client facilities within CICS for Remote Debug sessions

The assumed network in this chapter is a token-ring LAN connected to a host system via a 3745 communications controller equipped with a token-ring adapter. NCP and VTAM definitions are only examples and will vary with network characteristics. If you need additional assistance to configure your network, see the appropriate following publications, or contact your IBM representative:

- MVS/ESA Planning: APPC Management, GC28-1110
- VTAM Resource Definition Reference, SC31-6438
- VTAM Network Implementation Guide, SC31-6434
- NCP Resource Definition Reference, SC30-3448
- CICS/ESA: Resource Definition Guide, SC33-1166
- CICS/ESA: System Definition Guide, SC33-0664