3Com 520 - Manual (Page 65)

Routing IP and IPX A-11
IPX Routing
Novell IPX also uses RIP for routing purposes.
Although it is similarly named to the IP equivalent, it
uses a different protocol. IPX RIP broadcasts
datagrams out onto the network every sixty
seconds. Upon receipt of a RIP datagram, a router
adds one to the hop count of each route advertised
and broadcasts a RIP datagram to the other
networks, with which it is connected.
The cost of a route in an IPX network is determined
by the metric known as ticks . In a LAN only
environment this is the hop count plus one, e.g.
three hops or four ticks. For an internetwork
connected via a WAN or ISDN links, the tick count is
factored on the speed of the WAN link.
We saw above the common network numbering
scheme employed for a bridged network. By
employing routing, LAN A, LAN B and LAN C become
three separate networks on a network. The network
numbering must reflect that situation.
In a Novell IPX environment we could allocate IPX
network numbers 00000111 to LAN A, 00000222 to
LAN B and 00000333 to LAN C. Having configured
the ports of the OfficeConnect Remote to accept
this protocol, routing will now occur between the
remote network servers and workstations but
addressed by different network numbers.
It should be noted that NetWare 3.X and later, uses
the concept of internal IPX addresses, which is
somewhat similar to network addressing. The
internal address refers to the internal network within
that server allowing internal processes to
communicate. These numbers must be unique for
all servers right across the network. Although
network servers may appeared wired correctly, and
in other respects seem to be working correctly,
duplicated internal IPX addresses will not allow
correct operation.
NetWare has a hop count limitation imposed by the
RIP. On an IPX network a data packet can cross a
maximum of fifteen routers before being discarded.
Rc.bk : RCAPPA.FRM Page 11 Thursday, July 10, 1997 9:53 AM