Inside Macintosh: Networking With Open Transport / Part 1 - Open Transport Essentials

Chapter 14 - AppleTalk Service Providers

The AppleTalk service provider is an Open Transport provider that gives you access to zone and node information functions that are specific to the AppleTalk protocol family. AppleTalk networks use zones to define logical groups of users, and there are several Open Transport functions you can use to determine your endpoint's zone and the zone in your endpoint's network. Open Transport also provides a function that can supply information about your endpoint's AppleTalk environment. To use these functions, you must create a specialized Open Transport provider: an AppleTalk service provider.

The AppleTalk service provider is able to provide information about zones by implementing a subset of the Zone Information Protocol (ZIP), which maps network numbers to zone names for all networks belonging to an AppleTalk internet.

This chapter describes the AppleTalk service provider functions. You should read this chapter if you want to obtain

• the zone name for the node on which your application is running

• the names of the zones for the local network to which your application's node is connected

• the names of all the zones that exist throughout the AppleTalk internet to which your local network belongs

• information about the AppleTalk environment for a given node, including the address of a local router

For complete information about the functions and data structures introduced in this chapter, see "AppleTalk Service Provider Reference".

For an overview of the AppleTalk service provider and how it fits within the AppleTalk protocol stack, read the chapter "Introduction to AppleTalk". Zones are part of the NBP name used in the NBP address format; for more information on this format, read the chapter "AppleTalk Addressing". For a detailed description of the ZIP specification, see Inside AppleTalk, second edition.

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Chapter Contents

About AppleTalk Service Providers

Using AppleTalk Service Providers

Creating AppleTalk Service Providers

Working With AppleTalk Zones

Getting the Name of an Application's Zone

Getting a List of Zone Names

Getting Information About the Current AppleTalk Environment