Vanessa Avalos
Cisco Networking Academy Semester 3
Chapter 7
Novell Internet Packet Exchange Protocol (IPX)
IPX is another common networking protocol, in addition
to TCP/IP.
Novell Netware is a client/server protocol (Clients request
services, such as print and file access from servers).
NetWare is a proprietary suite of protocols including:
IPX – Layer 3, connectionless (like IP), defines network
and node access
Novell-RIP – Different from TCP/IP RIP
SAP – Service Advertising Protocol (SAP), to advertise
network services
NCP – NetWare Core Protocol (NCP) to provide client-to-server
SPX – Sequenced Packet Exchange, Layer 4, connection
orientated service (like TCP)
The IPX address is 80 bits done in the form of
network.node or 8bytes Hex.MAC address
The network address is assigned by the administrator.
The host address is usually the MAC address and is 12 Hex digits
in length. The network address is 8 Hex digits in length.
An example of an IPX address is: 4a1d.0000.0c56.de33
(Network address in pink, Node address in green.)
There are four types of Novell encapsulation, and
they are not compatible with each other. There are two names for
each. The Novell name and the Cisco name.
| Novell |
Cisco |
| Ethernet_802.3 |
novell-ether |
| Ethernet_802.2 |
sap |
| Ethernet_II |
arpa |
| Ethernet_snap |
snap |
802.3 raw is default on NetWare version 3.11 or earlier
802.2 sap, the standard for IEEE frame format is default
on NetWare version 3.12 or later
Ethernet ARPA is standard Ethernet_II used with TCP/IP
Ethernet SNAP extends the IEEE 802.2 header by adding
a Subnetwork Access Protocol (SNAP) header, which provides an "encapsulation
type" used with TCP/IP and Apple Talk
Cisco supports all the types of encapsulation even to
supporting multiple types on the same LAN
Novell uses RIP for routing.
Novell’s RIP uses ticks and hopcount for metrics.
The ticks are 1/18 sec and the maximum hop count is 15. Updates are
every 60 seconds
Novell RIP isn’t a very good choice for large networks
for the same reasons TCP/IP RIP isn’t. Because of frequent updates,
slow convergence time and a small number for maximum hop count.
Ticks can provide a measure of the speed of a path that
hop count can’t
If two paths have the same tick count, then the hop count
is compared
If they also have the same hop count then Novell RIP
will load balance.
Service Advertisement Protocol (SAP) allows network
to advertise their services Every service has a SAP identifier.
SAP updates are every 60 seconds
Some network devices and routers keep tables of known
services
| SAP service |
Number |
| Netware file service |
4 |
| Print service |
7 |
| Remote bridge service (router) |
24 |
Only servers keep these tables, clients do not.
Cisco allows use of the names instead of the numbers,
this can make troubleshooting easier.
These SAP updates use a lot of bandwidth. Routers
do not forward these broadcasts
GNS – Get the nearest Server
A type of SAP
When a client powers up and runs its client startup programs
it broadcasts a connection sequence to locate the nearest server to logon.
The broadcast is the GNS request, the server responds with the GNS response.
If there is no server on the local segment the router will respond to the
GNS with a server address from its SAP table
HOW TO CONFIGURE IPX
Start in global:
router(config)#ipx routing {node address}
If you don’t give it a node address, it uses the MAC
address. There is no MAC address for the serial port. If there
is no Ethernet connection it asks you to make a MAC address up.
router(config)#ipx maximum-paths {number of paths}
Thise does the load balancing. IPX can loadshare
if the paths have same ticks and hopcount. 1 is the default,
maximum is 512.
Interfaces – The 1st configured is the primary, and the
2nd is the secondary
Sub interfaces - a mechanism that allows a single interface
to think it is more than one
THERE IS NO 0.0 INTERFACE
Each interface handles a different encapsulation type.
There are 2 ways to put an encapsulation type on an interface:
One - with the secondary command - with the secondary
or with the subinterface, there is no difference between them.
Secondary:
Router(config)#int e0
Router(config-if)#ipx network 10a encap sap
Router(config-if)#ipx network 9a encap novell-ether secondary
Sub interface:
Router(config)#int e0
Router(config-if)#int e0.1
Router(config-if)#ipx encapsulation novell-ether
Router(config-if)#ipx network 9e
If)#interface e0.2
If)#ipx network 10c encap sap
Troubleshooting and Monitoring commands:
Show commands:
IPX interfaces – status and parameters of interfaces
IPX route – like ip route, gives routing table
IPX servers – sap table
IPX traffic – shows traffic
Debug commands:
IPX routing activity -
IPX sap advertisements –
Ping ipx {network.node}
Global config
Ipx delay – changes tick counts, for a LAN default is
1 – for a WAN the default is 6.