Internetwork Packet Exchange

IPX is a computer networking protocol used by Novell NetWare operating system in the late 1980s to mid 1990s.

IPX is used for mapping the data packets from one point to another point in the network through an internetwork.

At first, the use of IPX very much, before the advent of the Internet boom of the mid-1990s. At that time, computers and computer networks can run multiple network protocols, so almost all IPX-based network also run TCP / IP to allow Internet connectivity.

IPX addressing
IPX nodes has the following addressing scheme:

Logical networks are 32-bit address is a hexadecimal number with a range from 0x00000001 to 0xFFFFFFFE. This address is also called the network address (network address).
Each host has its node address of each, which by default is set to the MAC address used by the network card used by the nodes. Node address was added to the network address to create a unique identifier for the hosts on the network.

Similarities with IP
IPX network address, in concept, similar to IP addresses, ie the network ID part of the total length of 32-bit IP address (the IP address with its subnet mask set to the number 1). Given the node address using the MAC address of network card is used, then the protocols Address Resolution Protocol (ARP) was not needed.

When doing the routing, the entries in the IPX routing table are also the same as the IP routing table, ie the routing is done by using its network address, and any network address, the format network: nodes are used, the same way with the format of an IP address / subnet mask used in the IP routing table.

IPX over Ethernet
IPX can also be transmitted via Ethernet using four types of encapsulation, as follows:

IEEE 802.3, which is used in the old systems and involves IPX data that dimulasi directly after 802.3 frame header.
IEEE 802.2 (Novell)
IEEE 802.2 (SNAP).
Ethernet II.

Source : www.wikipedia.com