The EtherTalk Protocol

EtherTalk, a Data Link Layer protocol, forms a part of the AppleTalk protocol suite. Apple created AppleTalk as a networking system for its Macintosh computers. Data Link Layer protocols translate data packets into frames of bits to be transported over the network.

Function

• AppleTalk was designed to run over a variety of different physical media. EtherTalk is the interface for AppleTalk networks running over Ethernet. Its full name is the EtherTalk Link Access Protocol (ELAP).

Features

• AppleTalk data has to be packaged in a format that Ethernet can handle. This is the purpose of EtherTalk. It reformats data ready to be put onto the Ethernet cable. It also has to map between AppleTalk addresses and the addressing system used by Ethernet. EtherTalk has to apply three different headers to a data packet: a Subnetwork Access Protocol (SNAP) header, Logical Link Control (LLC) header and an Ethernet header.

Obsolescence

• Apple has ceased supporting AppleTalk and so its implementations are in decline. Apple now recommends TCP/IP for networking Apple Macintosh computers.