TCPTYPE parameter

Summary

Default value

UNKNOWN

Parameter type

System

Where set

User 0 CCAIN parameters

Related products

All

Introduced

Before Sirius Mods 6.7

Description

This parameter specifies the type of TCP/IP network to which Model 204 is connected. Generally, you can leave this parameter at its default value and let Janus automatically detect the type of TCP/IP you have on your machine.

If you specify type IBM, Janus detects and sets the type of IBM interface it will use:

• Under CMS, this is always IUCV.
• Under MVS, Janus will select the IBM interface in the following order: BPX (Unix System Services), HPNS, then IUCV.
• If multiple types are installed, Janus will select the interface in the following order for MVS: BPX, HPNS, IUCV, Interlink, then KNET. For CMS the order is IUCV, then KNET.

You can always override auto-detection by explicitly supplying a TCPTYPE parameter. The only reason to do this would be if you have multiple TCP/IP stacks installed and you want to force use of the non-preferred stack.

The valid TCPTYPE values are:

IBM

Specifies IBM TCP/IP. This means to auto-detect the “best” IBM TCP/IP interface. For CMS, this is always IUCV. For MVS, Janus will look for BPX, HPNS, then IUCV.

BPX

Specifies IBM BPX (Unix System Services) (MVS only).

HPNS

Specifies IBM HPNS (High Performance Native Sockets) (MVS only). Note that despite its name, HPNS's performance is not nearly as good as BPX's.

INTERLNK

Specifies InterLink TCP/IP (MVS only).

CSI

Specifies Connectivity Systems TCP/IP (VSE only).

Most of the communication with the TCP/IP address space is accomplished via a PST. Because of this, you may need to increase NSUBTKS by 1 before using Janus.