Determining Network Connectivity Strategies
Determining Network Connectivity Strategies |
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NetWare servers and Windows 2000 systems are made interoperable on the same network by using NWLink, Client Services for NetWare, and Gateway Services for NetWare. Windows 2000 Server provides services that coexist and are interoperable with Novell NetWare networks and servers. The NWLink IPX/SPX/NetBIOS Compatible Transport Protocol (NWLink) is included with Windows 2000. This protocol provides connectivity between Windows 2000 and Novell NetWare systems. Reasons for using IPX/SPX in a mixed environment and enabling IPX routing are:
Windows 2000 routing supports RIP for IPX, which is very similar in function to RIP for IP and Service Advertising Protocol (SAP) for IPX, a protocol that gives nodes such as file servers and print servers the ability to advertise their service names and IPX addresses. Servers that host services send periodic SAP broadcasts, and IPX routers and SAP servers receive the broadcasts and propagate the service information through SAP announcements, which are sent every 60 seconds.
The IPX network ID is a 4-byte identifier expressed as an 8-digit hexadecimal number. This network ID has to be unique, or network connection problems can occur for NetWare clients. The 4-byte IPX network ID is an address space that you can use to group IPX networks based on the following:
Internal vs. External Networks Internal networks are virtual networks inside Novell NetWare servers, Windows 2000 routers, and other IPX routers that are also hosting services. The designation of an internal network ensures proper routing to these services.
Networks for Various Ethernet Frame Types For IPX environments that need to support multiple Ethernet frame types, you need to configure each Ethernet frame type with its own IPX network ID.
Remote Access Networks When you use a computer running Windows 2000 as a remote access server, remote access clients are assigned an IPX network ID. By default, the remote access server chooses a unique IPX network ID. You can specify an IPX network ID or range of IPX network IDs so that remote access IPX traffic is identified by its source IPX network address.
Department or Geographic Location You can allocate portions of the IPX address space based on geography (by building or site) or department (such as sales or research). For example, in a large campus environment, all of the IPX networks in building 5 might use 5 as the first digit of their addresses.
Maximum Diameter The maximum diameter of RIP and SAP for IPX is 16 hops, the same as for RIP for IP. The diameter is a measure of the size of an internetwork in terms of the number of routers a packet must cross to reach its destination. Networks and services that are more than 16 hops away are considered unreachable.
Confining and Directing NetBIOS-over-IPX Traffic You can control NetBIOS-over-IPX traffic by disabling the propagation of NetBIOS-over-IPX broadcasts on specific interfaces and by configuring static NetBIOS names. For example, if a specific IPX network does not contain any nodes that use NetBIOS over IPX, then you can disable NetBIOS-over-IPX broadcast propagation on all of the router interfaces connected to that network.
Preventing the Propagation of SAP Broadcasts The Service Advertising Protocol (SAP) is used on IPX networks to inform network clients of available network resources and services. If there are SAP broadcasts that do not need to propagate throughout the entire internetwork, you can use SAP filtering to prevent the IPX services from being advertised outside of a group of IPX networks. For example, if you want to hide the file servers in the human resources department, configure the routers that are connected to the human resources network to filter SAP broadcasts corresponding to the file and print sharing services of the human resources file servers. Another reason is to reduce traffic sent to subnets that do not require SAP services.