Internetwork packet exchange (IPX)

The IPX protocol is the main protocol used to transfer data between a UnixWare system and a NetWare server.

The IPX protocol is a datagram, connectionless protocol that does not require an acknowledgment for each packet sent. Other NetWare protocols such as SPXII, SAP, RIP, and NCP are built on top of and require IPX.

The IPX protocol provides both IPX services and RIP services. As LAN drivers deliver packets to IPX, the IPX driver uses RIP to determine the route for packets outbound to other networks. Packets addressed to a local host are routed by IPX to the applications.

When setting up UnixWare, you will need to at least configure your IPX internal LAN address to enable UnixWare to communicate over the internetwork using IPX. If your network interface card is auto-configurable, this is done for you by the system; see ``IPX auto-discovery''.

NetWare servers also must have an IPX external address.

IPX addressing

IPX delivers packets using a 12-byte network address, which consists of three address components:

• Network address (4 bytes). Identifies a specific logical network or LAN on an IPX internetwork; all NetWare servers, routers and clients cabled to this segment with a common frame type must use the same network address.

• Node address (6 bytes). Identifies the individual nodes on the network. The factory-defined IPX number on the NIC usually defines node addresses for client workstations. Server machines can have a logical node address.

• Socket address (2 bytes). Identifies processes or functions within a node. The destination for a packet is the socket address.

Net	Node	Socket
01010393.	0123456789ab.	0451

 -----------------------------------------------
| Net      |  Node           |  Socket         |
|----------|-----------------|-----------------|
| 01010393.|  0123456789ab.  |  0451           |
|----------|-----------------|-----------------|

IPX auto-discovery

If a NIC was already installed in your system when you installed UnixWare, the auto-discovery feature automatically detected the IPX network number, frame type (MAC protocol), and network device name for the network(s) connected to your node. This option is activated at installation so IPX configuration is automatic unless you install additional network boards later or need to change your IPX configuration.

Each time you boot UnixWare or shut down to move your system to another physical location, IPX reconfiguration is unnecessary because auto-discovery takes care of that for you.

If you did not have a network board installed when you installed UnixWare, or if you want to add more network boards, only then is it necessary to reconfigure IPX using the scoadmin(1M) NetWare Setup utility or the nwcx(1nuc) command. You can also use these utilities to disable IPX auto-discovery, should you want to manually configure IPX addresses.