Chapter Thirteen The Other Protocols

Objectives You’ll get a brief overview of –IPX/SPX –NetBEUI –Appletalk How each protocol handles addressing The pros and cons of each protocol

IPX/SPX Internetwork Packet Exchange/Sequenced Packet Exchange –Developed by Xerox in the early 80s –Adopted and tweaked by Novell to become their protocol of choice in NetWare

Addressing in IPX/SPX 32-bit network address MAC address of interface becomes host address A socket number assigned to the process or application running on the device –This is NOT the same as the sockets discussed in the Transport layer. The station address –The combined network/host address

Configuring IPX/SPX If no network number is statically assigned, the host will send out a broadcast looking for a SAP server. The SAP server will assign an address. Correct frame type is necessary in IPX. –Auto Detect usually works pretty well.

Frame Types (Raw) –The typical Ethernet frame –An older frame type used by non-Ethernet protocols Ethernet II Ethernet SNAP

Routing in IPS/SPX If a packet isn’t addressed to the local network, the transmitting station will broadcast a RIP packet. Available routers with access to the target network number respond with their node address and the number of hops to target. Transmitting workstation picks the router with the fewest hops and transmits the packet.

Pros and Cons of IPS Pros –Light overhead on the individual workstations –Very easy to configure and hard to mess up Cons –Very HEAVY overhead on the network as a whole –A limited number of hops prevents extremely large networks (like the Internet)

NetBEUI NetBIOS Enhanced User Interface –Developed by Microsoft for early versions of NT –A Layer 2 protocol –No longer supported by Microsoft XP does not install NetBEUI by default, but the protocol can be added from the installation CD.

Pros and Cons of NetBEUI Pros –Easy to configure All you need is to put all workstations on the same workgroup, but make sure they have different names. –Extremely fast with low overhead on network and workstations Cons –Not routable

AppleTalk Developed by Apple Computer Corporation Has a lot of similarities to TCP/IP –Layered functionality –A robust collection of related protocols Moves data in datagrams

Addressing in AppleTalk Each host is assigned a node ID and an entity name. –The Node ID is similar to the IP address. –The entity name is similar to a NetBIOS name. Networks are numbered (like in IPX/SPX) with 16-bit network numbers. The Name Binding Protocol (NBP) resolves node IDs and entity names to MAC addresses.

Some AppleTalk Protocols (1 of 2) Datagram Delivery Protocol (DDP) provides point-to- point delivery of user data. Routing Table Maintenance Protocol (RTMP) allows routers to dynamically build routing tables. AppleTalk Echo Protocol (AEP) is Apple’s version of ICMP. AppleTalk Transaction Protocol provides connection- oriented data delivery services.

Some AppleTalk Protocols (2 of 2) AppleTalk Data Streaming Protocol (ADSP) provides jitter-free delivery of multimedia. AppleTalk Session Protocol (ASP) opens, maintains, and closes sessions.