MacIPX Gateway

Novell Internet Access Server 4.1 includes MACIPXGW.LAN, a LAN driver that enables your router to operate as a gateway between IPX networks and Macintosh clients running MacIPX applications on AppleTalk networks. Macintosh clients use this MacIPX gateway to exchange data with NetWare clients and to use the resources available on IPX networks.

The MacIPX gateway converts packets traveling in both directions between AppleTalk and IPX networks. An IPX packet generated on a Macintosh client and destined for the IPX network is encapsulated in an AppleTalk packet and forwarded to the MacIPX gateway. When the gateway receives the encapsulated packet, it removes the AppleTalk header and trailer and forwards the IPX packet to the IPX network.

Similarly, when an IPX packet from the IPX network reaches the MacIPX gateway, the gateway adds AppleTalk encapsulation and delivers the packet to a MacIPX client on the AppleTalk network.

Figure 1-16 shows a MacIPX gateway operating between an AppleTalk network and an IPX network having both PCs and Macintosh computers.

Figure 1-16.
Networks Connected by a MacIPX Gateway

NOTE: MacIPX is not an extension of AppleTalk networking. For this reason, the MacIPX gateway neither routes IPX packets across an AppleTalk network nor connects IPX networks across an AppleTalk cloud. Rather, the gateway enables Macintosh computers to participate in IPX networks and promotes multiplatform peer-to-peer connectivity.


Gateway and Client Addressing

Each MacIPX gateway must have a unique IPX network number. All the MacIPX clients using the MacIPX gateway are on that IPX network.

The IPX address of a MacIPX client using a MacIPX gateway consists of a network number and a node number. These are determined in the following way:

For example, if the MacIPX client on AppleTalk network 0x1234 with node ID 0xAA is using a gateway whose IPX network is 0x4321, the IPX address of the client is 4321:7A00001234AA.

NOTE: For MacIPX 1.1 and earlier, the node ID consists of 3 bytes of 0x00, followed by the 2-byte AppleTalk network number and 1-byte node ID.

The MacIPX gateway, by default, serves all AppleTalk networks that make up the AppleTalk cloud. You can, however, restrict the set of AppleTalk networks that the gateway serves. You do this through a file called MACIPXGW.DAT, which resides in SYS:SYSTEM. To configure this file, refer to Novell Internet Access Server 4.1 Routing Configuration.


Where to Locate a MacIPX Gateway on Your Network

You should locate a MacIPX gateway to minimize the amount of configuration required by MacIPX. For example, if you have an AppleTalk network for dial-in users that provides service for AppleTalk Remote Access (ARA), you should ensure that a MacIPX gateway serves the AppleTalk zone that includes the ARA network, so that Macintosh clients using ARA do not require MacIPX configuration.