ATALK(4) | Kernel Interfaces Manual | ATALK(4) |
The AppleTalk Protocol Suite provides support for five kinds of physical media: LocalTalk (230kbps wire-or'd serial), Ethernet, FDDI, Token Ring, and asynchronous serial connections (using either AppleTalk Remote Access (ARA) or PPP ). Currently, NetBSD's AppleTalk implementation supports Ethernet, FDDI, and Token Ring.
AppleTalk packets are encapsulated on the Ethernet using the EtherTalk Link Access Protocol (ELAP). Local network address resolution is handled using the AppleTalk Address Resolution Protocol (AARP). Neither of these protocols is exposed to user-mode applications.
Sockets in the AppleTalk protocol family use the following address structure:
struct sockaddr_at { uint8_t sat_len; sa_family_t sat_family; uint8_t sat_port; struct at_addr sat_addr; union { struct netrange r_netrange; char r_zero[8]; } sat_range; };
The port of a socket may be set with bind(2). The node for bind(2) must always be ATADDR_ANYNODE: “this node”. The net must be ATADDR_ANYNET. ATADDR_ANYNET corresponds to the machine's “primary” address (the first configured). The port of a socket and the primary address are returned with getsockname(2).
DDP is implemented in the kernel as SOCK_DGRAM sockets in the AF_APPLETALK address family. NetBSD implements all other AppleTalk protocols using the Netatalk package. Netatalk implements all functions except for ADSP and an AFP client. AEP, NBP, and ZIP services are provided by the atalkd daemon. ASP and ATP services are provided by a user library. PAP and AFP services are provided by user programs and daemons.
Gursharan S. Sidhu, Richard F. Andrews, and Alan B. Oppenheimer, Inside AppleTalk, second edition.
November 14, 1997 | NetBSD 6.1 |