Xerox network services

Xerox network services (XNS) is a protocol stack which provided routing and packet delivery developed by Xerox at Xerox PARC in the early 1980s. Novell based much of the lower layers of their protocol suite IPX/SPX[?] on XNS.

The main components are:

• Internet datagram protocol, IDP
• Routing information protocol, RIP
• Packet Exchange protocol, PEP
• Sequences packet protocol, SPP

It has strong parellels to TCP/IP in that the Network layer IDP is roughly equivalent to IP. RIP has the same functions (and obviously name) as the Routing information protocol, RIP. SPP a connectionless Transport layer protocol is similar to UDP. PEP is also in the Transport layer except connection-oriented[?] and is similar to TCP.

XNS specifically is no longer in use due to the all pervasiveness of IP.