Acacia High School:

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The main purpose of this TCS is to familiarize the students with the IPX routed protocol. Each student had to learn how the protocol functioned, how it differed from other routed protocols, and how to implement it onto a router.

The main learning objectives of the TCS were the following:

1. Describe the format for IPX addressing and how unique networks are identified.

Novell IPX addresses are unique and are different from normal IP addresses as they are 80 bits in length. That includes both a network number and a node number. the MAC address is incorporated as part of the logical address. In IPX the unique networks can be identified through the use of GNS (Get Nearest Server) protocols which are broadcasts that make an attempt to locate the nearest and quickest server.

2. Describe the function of the Service Advertisement Protocol (SAP) within IPX.

Within IPX the function of the SAP broadcast announces and locates registered network services. This protocol adds, finds, and removes services on the internetwork dynamically. Each SAP service is an object type identified by a hexadecimal number. For example the number 4 is for a NetWare file server, number 7 is for print servers, and number 24 is for remote bridge server (router). SAP also uses an aging mechanism to identify and remove table entries that have become invalid. Through the use of SAP's network updates are reduced therefore reducing the amount of excess network traffic.

3. Document the effects of implementing IPX on your network.

Implementing IPX can have a serious effect on your network. Because IPX uses lots of broadcasts in order for users of the network to be able to perform certain tasks such as printing, using IPX can have a big impact on your bandwidth.

One of the reasons that IPX uses so many broadcasts is because it is a client/server based protocol. When a user wants to perform a certain task, the machine must first send out a broadcast to locate the nearest server which can handle this task. These broadcasts are called GNS (Get Nearest Server.) Once the machine locates a server it can then begin performing its desired task.

Another type of broadcast used in IPX routing is called a SAP (Service Advertisement Protocol.) These are broadcasts that are sent out by the Netware servers that tell everyone on the network what services it can perform. Adding, finding, and removing services on the internetwork is dynamic because of SAP advertisements. Each SAP service is an object type identified by a hexadecimal number. For example, a Netware file server is the number 4, a print server is number 7, and a router is number 24.

I think that when we implement Novell IPX on our schools network it will have a decent impact on our bandwidth. Because of all the broadcasts that it uses, there will be an increase in traffic overall across the network. I think there will be even more traffic in the areas that are close to the Netware servers. The traffic will be mostly SAP’s and GNS’s as far as the IPX goes. There will still be other traffic on our network because we are running multiple routing protocols (IP and IPX.)

Although implement IPX on a network could be an efficient way to do things, I feel that it will have a negative impact on our network because with all of the broadcasts from the IPX combined with all of the ARP and RARP of the IP which would still be running I think that it would just completely bog down our bandwidth.

4. How to implement IPX on a router.

Prompt		Command
router-d>		enable
Password:		cisco
router-d#		config t
router-d(config)#		ipx routing
router-d(config)#		exit
router-d#		copy run start
router-d#		exit

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