C H A P T E R35
• Describe the development history of the AppleTalk protocol, used almost exclusively in Macintosh
• Describe the components of AppleTalk networks and extended network.
• Discuss the primary characteristics of the AppleTalk protocol.
• Discuss the addressing methods of AppleTalk.
• Describe additional protocols implemented in AppleTalk networks, including protocols used in the
upper layers of the OSI reference model.
AppleTalk, a protocol suite developed by Apple Computer in the early 1980s, was developed in
conjunction with the Macintosh computer. AppleTalk’s purpose was to allow multiple users to share
resources, such as files and printers. The devices that supply these resources are called servers, while the
devices that make use of these resources (such as a user’s Macintosh computer) are referred to as clients.
Hence, AppleTalk is one of the early implementations of a distributed client/server networking system.
This chapter provides a summary of AppleTalk’s network architecture.
AppleTalk was designed with a transparent network interface—that is, the interaction between client
computers and network servers requires little interaction from the user. In addition, the actual operations
of the AppleTalk protocols are invisible to end users, who see only the result of these operations. Two
versions of AppleTalk exist: AppleTalk Phase 1 and AppleTalk Phase 2.
AppleTalk Phase 1, which is the first AppleTalk specification, was developed in the early 1980s strictly
for use in local workgroups. Phase 1 therefore has two key limitations: Its network segments can contain
no more than 135 hosts and 135 servers, and it can support only nonextended networks. Extended and
nonextended networks will be discussed in detail later in the sections “Extended Networks” and
AppleTalk Phase 2, which is the second enhanced AppleTalk implementation, was designed for use in
larger internetworks. Phase 2 addresses the key limitati