Novell Internet Packet Exchange (IPX)

Novell IPX

• IPX is a connectionless layer 3 protocol like IP. An IPX address is made up of 32 bits network and 48 bits MAC address (80 bits in total). It is important you know the length of these in binary and hexadecimal.
• SPX (Sequenced Packet Exchange) is a connection-orientated layer 4 protocol similar to TCP.
• NCP (Netware Core Protocol) - Client server connections and applications communication.
• SAP (Service Advertising Protocol) - Advertises network services.
• NLSP (Netware Link Services Protocol) - Link state routing protocol.
• GNS (Get Nearest Server) - A type of SAP advertisement used to locate a server for client log-in.

Netware 2 - 3.11 (1983-1985)
Ethernet_802.3 (default encapsulation on Cisco routers) Cisco name novell-ether. Also called Ethernet raw.

Netware 3.12 - 4.x (1985 - )
Ethernet_802.2 Cisco name sap (service access points) This is standard IEEE format and includes LLC header.

Ethernet_II
Ethernet_II uses TCP/IP Cisco name arpa. Novell 5.0 onwards uses TCP/IP instead of IPX.

Ethernet_SNAP
Cisco name snap (Subnetwork Access Protocol)

Default Encapulations

• Ethernet - novell-ether
• Token Ring - sap
• FDDI - snap

Novell IPX RIP

• Incompatible with IP RIP.
• 2 Metrics used (Hops, Ticks).
• Max hop count 15.
• Updates every 60 sec.
• Not efficient for large networks

IPX and Cisco routers

• Cisco routers maintain routing tables for each IPX protocol enabled on the network.
• Routers can provide network-based LAN sharing on IPX server-less LAN segments.
• Each network address must use a distinct IPX encapsulation.
• Subinterfaces on routers are used to assign multiple network numbers and encapsulations on single interfaces.

IPX IOS Router Configuration

Router(config)# ipx routing
                                    Router(config)# ipx maximum paths x (default 1, max 512)
                                    Router(config)# int e0.1
                                    Router(config-if)# encapsulation novell-ether
                                    Router(config-if)# ipx network 9e
                                    

ipx delay <number> - used to manually set the tick metric delay on an interface. Default values for interface delays are LAN = 1 tick, WAN = 6 ticks.

Router IPX Troubleshooting

Show ipx interface  - status / parameters (IPX RIP
                                    and SAP info)
                                    Show ipx route - routing table
                                    Show ipx servers  - server list)
                                    Show ipx traffic  - number / type of packets
                                    Show protocol - IPX address of an interface
                                    Debug ipx routing activity - info on RIP updates
                                    Debug ipx sap - info on Sap updates
                                    Ping
                                    

SAP Service Advertising Protocols

• 4 - Netware File Server
• 7 - Print Server
• 24 - Remote bridge server (router)

• SAP packets sent every 60 seconds.
• Routers build SAP tables.
• Routers only respond to GNS requests when servers are not local.