Cisco - Novell IPX

	Internetworking Technologies Instructor: Prabul, CCNA
	Internetworking Technologies Instructor: Prabul, CCNA

7. Novel Networks(IPX)

Top 10 Graphics:

Novell IPX is similar to TCP/IP and will operate within the same network implementation and the same route - provided you have a multiprotocol route. Some of its' characteristics are:

Used in a client / server environment
(network access transparent to users)
IPX address is 80 bits (32-bits network + 48-bits node)
(each device has a unique address)
Interface MAC address is part of the logical address (node)
(eliminates the need for an Address Resolution Protocol (ARP))
Multiple LAN data-link encapsulations per interface
(multiple logical networks on an individual interface; each network requires a single encapsulation type)
Default routing protocol is Novell RIP
(Novell RIP uses the distance vectors of ticks and hops)
SAPs and GNS broadcasts function to connect clients and servers.
(Novell services are advertised using SAP)
(NetWare clients find servers with GNS (Get Nearest Server) packets)

The NetWare protocol stack supports all common media access protocols. The data link and physical layers are accessed through the Open Data Link (ODI) interface.

Cisco routers offer the following features in Novell environments:

Access lists and filters for IPX, RIP, SAP, and NetBIOS
SAP output filter can be imployed to conserve bandwidth
Scalable routing protocols, including Enhanced IGRP and NLSP
Configurable RIP and SAP updates and packet sizes
Serverless LAN support
Rich diagnostics, management, and troubleshooting features

NetWare - Popular distributed NOS developed by Novell. Provides transparent remote file access and numerous other distributed network services.

IPX (Internetwork Packet Exchange) - NetWare network layer (Layer 3) protocol used for transferring data from servers to workstations. IPX is similar to IP and XNS.

Datagram, connectionless protocol that does not require an acknowledgment for each packet.
Layer 3 protocol that defines the internetwork and internode addresses.

SPX (Sequenced Packet Exchange) - Reliable, Transport Layer (Layer 4) connection-oriented protocol that supplements the datagram service provided by Network layer (Layer 3) protocols. Novell derived this commonly used NetWare transport protocol from the SPP of the XNS protocol suite.

Service for Layer 4 connection-oriented services

SAP (Service Advertisement Protocol) - IPX protocol that provides a means of informing network clients, via routers and servers, of available network resources and services.

GNS (Get Nearest Server) - Request packet sent by a client on an IPX network to locate the nearest active server of a particular type. An IPX network client issues a GNS request to solicit either a direct response from a connected server or a response from a router that tells it where on the internetwork the service can be located. GNS is part of the IPX SAP.

NCP (NetWare Core Protocol) - Provides client-to-server connections and applications. (network access transparent to users)

NetBIOS (Network Basic Input/Output System) - API used by applications on an IBM LAN to request services from lower-level network processes. These services might include session establishment and termination, and information transfer.

NLSP (NetWare Link Services Protocol) - Link-state routing protocol based on IS-IS. The Cisco implementation of NLSP also includes MIB variables and tools to redistribute routing and SAP information between NLSP and other IPX routing protocols.

How to determine the IPX address:

Ask the NetWare administrator
Use a Cisco IOS command (CDP) to check on the neighbor Cisco router
- The CDP command summarizes protocols and addresses on target
Test the Application Later using 'Telnet'
- Telnet to the neighbor router and use the
  'show protocols' or
  'show IPX interface' command
- Can the remote router be accessed?
Use a NetWare command to check on the NetWare file server/router
- Attach or log in and use the NetWare config utility

NOTE: Assign the same IPX network number(s) to the router that are in use by the IPX devices connected to that router, whether the interface is a LAN or WAN connection.

CDP (Cisco Discovery Protocol) - Media and protocol independent device discovery protocol that runs on all Cisco manufactured equipment including routers, access servers, bridges, and switches. Using CDP, a device can advertise its existence to other devices and receive information about other devices on the same LAN or on the remote side of a WAN. Runs on all media that support SNAP, including LANs, Frame Relay, and ATM media.

NetWare allows multiple different Layer 2 frame structures (encapsulations) for Novell IPX packets. Cisco routers support all of these the framing variations.


[ Novell Name    ][ Framing Structure ]
 ----------------  -------------------
1. Ethernet_802.3   [802.3][IPX]  (raw Ethernet)
                    - default for NetWare 3.11 or earlier)
2. Ethernet_802.2   [802.3][802.2 LLC][IPX]  (OSI routing)
                    - default for NetWare 3.12 or later)
3. Ethernet_II      [Ethernet][IPX]
                    (Used with TCP/IP)
4. Ethernet_SNAP    [802.3][802.2 LLC][SNAP][IPX]
                    (Used with TCP/IP and AppleTalk)

Encapsulation - The wrapping of data in a particular protocol header. For example, Ethernet data is wrapped in a specific Ethernet header before network transit. Also, when bridging dissimilar networks, the entire frame from one network is simply placed in the header used by the data link layer protocol of the other network.

Tunneling - Architecture that is designed to provide the services necessary to implement any standard point-to-point encapsulation scheme.

Note: Multiple encapsulations can be specified on an interface, but only if multiple network numbers have also been assigned. Although several encapsulation types can share the same interface, clients and servers with different encapsulation types cannot communicate directly with each other.

Cisco Encapsulations:
            [ Novell IPX Name ][ Cisco IOS Name ]
Ethernet      Ethernet_802.3     novell-ether
              Ethernet_802.2     sap
              Ethernet_II        arpa
              Ethernet_SNAP      snap
Token Ring    Token-Ring         sap
              Token-Ring_SNAP    snap
FDDI          FDDI_SNAP          snap
              FDDI_802.2         sap
              FDDI_Raw           novell-fddi

Specify encapsulation type when you configure IPX networks
Make sure the encapsulations on the clients, servers, and routers all match

The default encapsulation types on Cisco router interfaces and their keywords are:

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

Note: The default Ethernet encapsulation type on Cisco routers does not match the default Ethernet encapsulation type on Novell servers after NetWare 3.11.

Novell uses Novell RIP for routing. Novell RIP checks its two distance vector metrics by first comparing the ticks for path alternatives. If two or more paths have the same tick value, Novell RIP compares the hop count. If two or more paths have the same hop count, the router will load share based on the IPX maximum-paths command.

Uses ticks (about 1/18 sec) and hop count (maximum of 15 hops)
Broadcasts routing information to neighbor routers every 60 seconds

SAP (Service Advertizements Protocol) - All servers and routers keep a complete list of the services available throughout the network in server information tables. SAP uses an aging mechanism to identify and remove table entries that become invalid.

SAP packets advertize all NetWare network services
Service Advertisements occur at 60-second intervals
Adding, finding, and removing services on the internetwork is dynamic because of SAP advertisements
Can add excessive broadcast traffic to the network
Routers do not forward SAP broadcasts. Instead, each router builds its own SAP table and forwards the SAP table to other routers. By default this occurs every 60 seconds but the router can use access lists to control the SAPs accepted or forwarded.

Each SAP service is an object type identified by a hexadecimal number:

4 NetWare file server
7 Print server
24 Remote bridge server (router)

GNS Get Nearest Server protocol (SAP query):

GNS is a broadcast from a client needing a server
NetWare servers and Cisco routers get this SAP packet
NetWare servers provide GNS response
Cisco router will not respond to the GNS request. If there are no NetWare servers on the local network, the Cisco router will respond with a server address from its own SAP table.

Novell IPX configuration Tasks:

Global Configuration
- Start IPX routing process
- Enable Load sharing (if appropriate)
Interface Configuration
- Assign unique Network numbers
- Set the (optional) Encapsulation type


Router(config)# ipx routing [node address]

enables Novell IPX routing
If no node address is specified, the Cisco router uses the MAC address of the interface
If a Cisco router has only serial interfaces, an address must be specified


Router(config)# ipx maximum-paths paths

Configures round-robin load sharing over multiple equal metric paths
paths - Maximum number of parallel paths to the destination; the default is 1 and the maximum is 512


Router(config-if)# interface type number.subinterface-number
Router(config-if)# ipx network network [encapsulation encap-type]

Specify a subinterface, then enable IPX routing with encapsulation type


Router(config-if)# ipx network network [encapsulation encap-type]
                   [secondary]

Assign primary and secondary network number and encapsulation

Subinterface - One of a number of virtual interfaces on a single physical interface:

Allows a single physical interface to support multiple logical interfaces or networks.
Several logical interfaces or networks can be associated with a single hardware interface.
Each subinterface must use a distinct encapsulation, and the encapsulation must match that of the clients and servers using the same network number.

Novell IPX Configuration example:


Router(config)# ipx routing

Selects IPX for routing, and starts IPX RIP


Router(config)# ipx maximum-paths 2

Allows load sharing over parallel metric paths to the destination. The number of parallel paths used is limited to two


Router(config-if)# interface ethernet 0.1

Indicates the first subinterface on interface E0


Router(config-if)# ipx encapsulation novell-ether

Specifies that Novell's unique frame format is used on this network segment. Cisco's keyword is novell-ether; Novell's terminology is Ethernet_802.3


Router(config-if)# ipx network 9e

Network number assigned to subinterface E0.1


Router(config-if)# interface ethernet 0.2

Indicates the second subinterface on interface E0


Router(config-if)# ipx network 6c encapsulation sap

Network number assigned to subinterface E0.2


Router(config-if)# interface ethernet 1
Router(config-if)# ipx network 4a encapsulation sap

Specifies that Ethernet 802.2 frame format is used on this network segment. Cisco's keyword is sap


Router(config-if)# interface serial 0
Router(config-if)# ipx network 1

Verfying IPX operation:

Monitoring Commands:

show ipx interface (IPX status and IPX parameters configured)
show ipx route (IPX Routing table contents)
show ipx servers (IPX server list - discovered through SAP)
show ipx traffic (Number and type of packets received/transmitted)

Troubleshooting Commands:

debug ipx routing activity (Information about RIP update packets)
debug ipx routing sap (Information about SAP update packets)

SAP responses may be one of these types:

0x1 - General query

0x2 - General response

0x3 - Get Nearest Server request

0x4 - Get Nearest Server response

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