Internetwork Packet Exchange or IPX networks is the networking protocol that interconnects different networks that make use of Novell’s NetWare servers and clients. IPX is the datagram/packet protocol and works at a Network layer of the communication protocols & is connectionless (it does not need that the connection gets maintained during the exchange of packets, for example, the voice phone call). One such IPX network product is https://www.syniverse.com/products/ipx-network.
Packet acknowledgment generally gets managed by Novell protocol, Sequenced Packet Exchange, or SPX. Some related Novell NetWare systems are Routing Information Protocol, Service Advertising Protocol, and NetWare Link Services.
How Does IPX Work?
Internetwork Packet Exchange is a network layer & SPX is a transport layer of IPX and SPX network protocol. IPX & IP protocol has got the same functions and it defines how data gets sent or received between two devices. This transport layer protocol is used for establishing & maintaining the right connection between two devices. And together, they are used for transferring data and create the network connection between the systems of IPX Networks.
IPX doesn’t need a consistent connection to maintain whereas packets are sent from a particular system to another, it is called connectionless. It will resume the transfer from a point where this was interrupted because of power loss or a bad connection.
When the IPX client gets booted on the NetWare internetwork by using IPX routers, the client broadcasts the Get Nearest Server request message to the locally connected network to find the nearest server. Suppose the NetWare server cannot be found on a connected network, the router informs about the nearest accessible server based on your connection cost. The router is quite familiar with the information as NetWare servers by using IPX that notifies the network of the presence by using SAP that allows the IPX routers to build server tables that are based on the SAP numbers.
Features of IPX-EIGRP
IPX-EIGRP offers the following features:
Automatic redistribution – The IPX-RIP routes are redistributed automatically in EIGRP, so IPX-EIGRP routes can automatically be redistributed in RIP, with no commands getting entered by the user. Redistribution will get turned off with the use of no redistribute subcommand. Both IPX-EIGRP and IPX-RIP will be turned off totally on a router.
Improved network width – If using IPX-RIP, the biggest possible width of the network comes to 15 hops. And when IPX-EIGRP gets enabled, the biggest possible width comes to 224 hops. As the EIGRP metric is large enough for supporting several hops, and the only barrier for expanding this network is the transport layer counter. There is no doubt that Cisco works over this problem just by incrementing this transport control field while the IPX packet traversed 15 routers & the next hop to a destination was learned through EIGRP. When the RIP route is used as the next hop to the destination, then the transport control field gets incremented as normal.
Incremental updates – Total SAP updates will be sent regularly until the EIGRP neighbor is seen and thereafter when there’re changes to the SAP table. It works by taking benefit of the EIGRP’s reliable transport server so IPX-EIGRP peer should be present for the SAPs to be delivered. Suppose there is no peer on an interface, periodic SAPs are sent on the interface until the peer is found. And this functionality is automatic on the serial interfaces and can be configured on the LAN media in case desired IPX Networks.
When Router Forwards the IPX Packet
When you are forwarding the packets, the router will take possible actions. Suppose this packet gets destined for the network number where the router is connected directly, the router performs the following task:
- This router places the node address from an IPX header in Destination Address MAC header field.
- Router places own node address of MAC header.
IPX/SPX is perfect for the local area networks and private networks that have different protocol or communication functions. Just like IP, even IPX has end-user data, like IP & network addresses. And SPX is totally connection-oriented and used for the connection-related features & data routing.
Suppose the Transport Control field is equal to the maximum hop count before a field gets incremented, the router discards this packet. For the RIP routers, this hop count limit will be 16; and for the NLSP routers, the limit will be set between 8 & 127. Note that the broadcast packets are not rebroadcast on a network segment from where they’re received.