INTERNETWORKING III

CHAPTER 7 STUDY GUIDE

Novell NetWare is a network operating system (NOS), which connects PCs and other clients to NetWare servers. NetWare servers provide a variety of network services to their clients, including file sharing, printer sharing, directory services, and Internet access. Many NetWare servers function as application platforms for shared databases and as Internet and Intranet servers. With more than 5 million networks and more than 50 million clients, Novell has the largest share of the NOS market.

1.     In addition to Transmission Control Protocol/Internet Protocol (TCP/IP), Novell's Internetwork Packet Exchange (IPX) is another protocol that is commonly implemented in the networking industry. Until Novell's NetWare 5.0 release in 1998, all NetWare networks used IPX. As with AppleTalk, Novell migrated NetWare to IP. Therefore, IPX networks are networks that must still be supported due to their installed base

2.     Novell NetWare is a proprietary suite of protocols and includes the following:

·        IPX - a connectionless layer 3 protocol, that does not require an acknowledgment for each packet and defines the network and node addresses and operates within the same network implementation as TCP/IP.

·        Novell RIP - which is different from its IP counterpart—to facilitate the exchange of routing information.

·        Service Advertising Protocol (SAP) - to advertise network services

·        NetWare Core Protocol (NCP) - to provide client-to-server connections and applications.

·        Sequenced Packet Exchange (SPX) - service for Layer 4 connection-oriented services.

3.     IPX uses distance-vector routing such as RIP or link-state routing such as NetWare Link Services Protocol (NLSP). IPX RIP sends routing updates every 60 seconds. RIP uses ticks (network delay) and hop count as its routing metrics and is limited to a maximum of 16 hops.

4.     Novell IPX addressing uses a two-part address-the network number which is assigned by the network administrator and can be up to 8 base 16 (hexadecimal) digits in length; and the node number which is usually the Media Access Control (MAC) address. Novell IPX supports multiple logical networks on an individual interface; each network requires a single encapsulation type.

In summary,

·        Address is 80 bit (network.node)**

·        MAC address is part of its logical address

·        Multiple enacapsulations per interface

·        Default routing protocol is Novell RIP

·        Novell services are advertised using Service advertisement protocol (SAP)

·        NetWare clients find servers with Get Nearest Server (GNS) broadcast packets

5.     **Novell uses an all hexadecimal numbering system. As you know, a hexadecimal number is represented by two digits. By melding together the network number of 8 digits—AABBCCDD (Note that this is 4 bytes long or 4 bytes x 8 bits = 32 bits.) and the MAC/node address of 12 digits—A1B1C1D1E1F1 (Note that this is 6 bytes long or 6 bytes x 8 bits = 48 bits.) Novell comes up with a logical address for that particular device. The use of the MAC address in the logical IPX address eliminates the need for Address Resolution Protocol (ARP).

6.     If you cannot obtain an IPX address from the network administrator, you can get the IPX address directly from a neighbor router by telnetting to the neighbor router and use the show protocols or show ipx interface command.

7.     NetWare supports multiple encapsulations (that is, frame types) for the Ethernet family of protocols, all of which are supported by Cisco routers. The most important thing to remember about these four frame types is that they are not compatible with each other. If a Novell server uses 802.3 framing, and a Cisco router is configured to encapsulate using 802.2, then these two nodes cannot talk to each other. The Cisco IOS software and Novell terms for these encapsulations are:

·        Ethernet 802.3 is also called raw Ethernet and is the default for NetWare versions 2 through 3.11.

·        Ethernet 802.2 or SAP (also called Novell Ethernet_802.2 or 802.3) is the standard IEEE frame format, including an 802.2 LLC header. With the release of NetWare 3.12 and 4.x, this encapsulation became Novell's new standard frame format and is also used for OSI routing.

·        Ethernet II or ARPA (also called Novell Ethernet_II or Ethernet Version II) uses the standard Ethernet Version II header and is used with TCP/IP.

·        Ethernet SNAP or just snap (also called Novell Ethernet_SNAP or snap) extends the IEEE 802.2 header by adding a Subnetwork Access Protocol (SNAP) header, which provides an "encapsulation type" code similar to that defined in the Ethernet Version II specification and used with TCP/IP and AppleTalk.

8.     Multiple encapsulations are supported on a single LAN interface, allowing older and newer NetWare nodes to coexist on the same LAN segment as long as you configure multiple logical networks.

9.     What encapsulation type will the router use for IPX if none is specified?

Ethernet_802.3 (NetWare ver. 2 through 3.11); Ethernet_802.2 (NetWare 3.12 or later)

10.  NetWare's SAP allows network resources, including file and print servers, to advertise their network addresses and the services they provide. Each service is identified by a number, called a SAP identifier. SAP updates are sent every 60 seconds.

11.  Fill in the Cisco IOS name reference for the Novell IPX name.

12.  Workstations do not keep SAP tables-only routers and servers keep SAP tables. However, although service advertisements might work well on a LAN, broadcasting services can require too much bandwidth to be acceptable on large networks, or in networks linked on WAN serial connections. Routers do not forward SAP broadcasts. Instead, each router builds its own SAP table and forwards the SAP table to other routers.

13.  Scenario: A Novell client requests a particular network service and sends out a GNS request. There is a NetWare server on the same LAN segment.
Question: Which device responds to the request? NetWare Server or Router

server

14.  Scenario: A Novell client requests a particular network service and sends out a GNS request. There is not a NetWare server on the same LAN segment.
Question: Which device responds to the request? NetWare Server or Router

router

15.  Configuring the router for IPX routing involves both global and interface tasks. Global IPX configuration tasks include the following:

·        Start the IPX routing process using the command:
router(config)# ipx routing

·        Enable load sharing of 10 for your network using the command:
router(config)# ipx maximum-paths 10.

16.  Each IPX network on an interface must use a distinct encapsulation, and it should match that of the clients and servers using the same network number. Assigning the second network number is necessary if an additional encapsulation type is linked to an individual network. To assign network numbers to interfaces that support multiple IPX networks, you normally use subinterfaces. This is a mechanism that allows a single physical interface to support multiple logical interfaces or networks. That is, several logical interfaces or networks can be associated with a single hardware interface. Each must use a distinct encapsulation, and the encapsulation must match that of the clients and servers using the same network number.

17.  The default tick metrics for an IPX network on a Cisco router interface are:

·        For LAN interfaces, 1 tick(s)

·        For WAN interfaces, 6 tick(s)

You use the command ipx delay [number], where [number] is the ticks to associate with an interface.

18.  The show ipx interface command displays information about IPX routing update packets that are transmitted or received.

19.  The debug ipx sap command displays information about IPX SAP packets that are transmitted or received.

Command Reference

Chapter Seven

Novell IPX