3Com CoreBuilder 2500 - How IPX Routing Works; IPX Packet Format

6-4 CHAPTER 6: ROUTING WITH IPX
How IPX Routing
Works
A router operates at the network layer of the OSI Reference Model. The
router receives instructions to route packets from one segment to
another from the network-layer protocol. IPX, with the help of RIP,
performs network-layer tasks, including:
■ Addressing packets
■ Routing packets
■ Switching packets
This section describes the “IPX Packet Format” and the process of “IPX
Packet Delivery.”
IPX Packet Format An IPX packet consists of a 30-byte header followed by packet data. The
network, node, and socket addresses for both the destination and source
are in the packet header.
Figure 6-2 shows the IPX packet format.
Figure 6-2 IPX Packet Format
Checksum
Packet length
Transport control
Destination network
Destination node
Destination socket
Source network
Source node
Source socket
Packet data
Packet type
(2 bytes)
(2 bytes)
(1 byte)
(2 bytes)
(2 bytes)
(6 bytes)
(4 bytes)
(4 bytes)
(6 bytes)
(1 byte)
Packet header