TCPTYPE parameter
- Default value
- UNKNOWN
- Parameter type
- System
- Where set
- User 0 CCAIN parameters
- Related products
- All
- Introduced
- Before Sirius Mods 6.7
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.