Channel-attached network devices

At this stage, we have discussed in detail channel connection types, but what is being attached at the other end of the channel? As mentioned earlier, it is often a control unit with DASDs attached. In a networking context, however, the device attached at the other end can be a router.

Routers

In order to have z/OS talk to a channel-attached router, a protocol above the channel protocol must be agreed upon. The protocol used for this is called CLAW. CLAW stands for Common Link Access to Workstation. CLAW can be used to talk to either a CISCO CIP (Channel Interface Processor) host or an AIX pSeries host. CLAW-connected hosts are steadily becoming less common in z/OS networks.

Connecting to other LPARs

The parallel channel can of course be used to connect two LPARs directly, or even two separate central processor complexes. The other LPAR could be running z/OS, or it could be running z/VM with multiple Linux images within a single LPAR.