What is AppleTalk Routing?

AppleTalk Phase I was originally designed for local work groups. AppleTalk Phase II extends the number of nodes in an internetwork to over 16 million and the number of zones per port to 254. The Avaya switch supports both AppleTalk Phase I and Phase II. However, the translation from AppleTalk Phase I to Phase II is not supported.

Note: The Avaya P580 and P882 Multiservice switches support AppleTalk over Ethernet only.

The supported Ethernet versions are:

• Ethernet SNAP
• Ethernet II

The Avaya P580 and P882 Multiservice switches support the following AppleTalk protocols:

• AppleTalk Address Resolution Protocol (AARP)

This is an AppleTalk support protocol that maps the hardware address of an AppleTalk node to an Appletalk protocol address.

• Routing Table Maintenance Protocol (RTMP)

This protocol maintains information about AppleTalk addresses and connections between different networks. Specially, it tells each router to:

• Learn a new route to other routers
• Delete a route if the local router has not broadcast that route to the network for a certain period of time.
• Name-Binding Protocol (NBP)

This protocol translates alphanumeric entity names to AppleTalk addresses. NBP maintains a table of node addresses and entities within each node. Because each node also maintains it own list of named entities, the name directory within an AppleTalk network is not centralized. The names directory database is distributed among all nodes on the intranetwork.

• Datagram Delivery Protocol (DDP)

This protocol transfers data in packets called datagrams.

• AppleTalk Echo Protocol (AEP)

This protocol is used to send datagrams to other nodes in the network. The transmitted AEP datagram causes the destination node to return, or echo, that datagram to the sending node. This protocol determines whether a node is accessible before any sessions are started, and it enables users to estimate the round-trip delay time between nodes.

• Zone Information Protocol (ZIP)

AppleTalk routers use this protocol to map network numbers to zones. Each AppleTalk router maintains a Zone information Table which lists the zone-to-network mapping information.

For more detailed information about these protocols, see the AppleTalk documentation.