AppleTalk
Encyclopedia
AppleTalk is a proprietary
suite of protocols
developed by Apple Inc. for networking computers. It was included in the original Macintosh
released in 1984, but is now unsupported as of the release of Mac OS X v10.6
in 2009 in favor of TCP/IP networking. AppleTalk's Datagram Delivery Protocol corresponds closely to the Network layer of the Open Systems Interconnection (OSI
) communication model.
of protocol layering. Unlike most of the early LAN
systems, AppleTalk was not built using the archetypal Xerox XNS system. The intended target was not Ethernet
, and it did not have 48-bit addresses to route. Nevertheless, many portions of the AppleTalk system have direct analogs in XNS.
One key differentiation for AppleTalk was it contained three protocols aimed at making the system completely self-configuring. The AppleTalk address resolution protocol (AARP) allowed AppleTalk hosts to automatically generate their own network addresses, and the Name Binding Protocol (NBP) was a dynamic system for mapping network addresses to user-readable names. Although systems similar to AARP existed in other systems, Banyan VINES
for instance, nothing like NBP has existed until recently.
Both AARP and NBP had defined ways to allow "controller" devices to override the default mechanisms. The concept was to allow routers to provide the information or "hardwire" the system to known addresses and names. On larger networks where AARP could cause problems as new nodes searched for free addresses, the addition of a router could reduce "chattiness." Together AARP and NBP made AppleTalk an easy-to-use networking system. New machines were added to the network by plugging them and optionally giving them a name. The NBP lists were examined and displayed by a program known as the Chooser which would display a list of machines on the local network, divided into classes such as file-servers and printers.
, which would consist of a host machine providing routing, printer sharing and file sharing. However this project was canceled in 1986. Despite this, the LaserWriter
included built-in AppleTalk. Apple later released an AppleTalk server suite known as AppleShare
, and included basic AppleTalk features as the default network protocol in later releases of "classic" Mac OS (System).
With the introduction of Mac OS X
, AppleTalk was largely displaced. Internet-based
protocols were used as the defaults, although AppleTalk was supported for backwards compatibility at first. Mac OS X v10.5
was the last Apple OS to support AppleTalk.
AppleTalk is largely based on the (unpatented) Cambridge Ring
.
Because of this dynamism, users could not be expected to access services by specifying their address. Instead, all services had names which, being chosen by humans, could be expected to be meaningful to users, and also could be sufficiently long enough to minimize the chance of conflicts.
Note that, because a name translated to an address, which included a socket number as well as a node number, a name in AppleTalk mapped directly to a service being provided by a machine, which was entirely separate from the name of the machine itself. Thus, services could be moved to a different machine and, so long as they kept the same service name, there was no need for users to do anything different to continue accessing the service. And the same machine could host any number of instances of services of the same type, without any network connection conflicts.
Contrast this with A records in the DNS
, where a name translates only to a machine address, not including the port number that might be providing a service. Thus, if people are accustomed to using a particular machine name to access a particular service, their access will break when the service is moved to a different machine. This can be mitigated somewhat by insistence on using CNAME records indicating service rather than actual machine names to refer to the service, but there is no way of guaranteeing that users will follow such a convention. (Some newer protocols, such as Kerberos and Active Directory
use DNS SRV record
s to identify services by name, which is much closer to the AppleTalk model.)
, usually MAC
, addresses. It is functionally equivalent to ARP
.
AARP is a fairly simple system. When powered on, an AppleTalk machine broadcasts an AARP probe packet asking for a network address, intending to hear back from controllers such as routers. If no address is provided, one is picked at random from the "base subnet", 0. It then broadcasts another packet saying "I am selecting this address", and then waits to see if anyone else on the network complains. If another machine has that address, it will pick another address, and keep trying until it finds a free one. On a network with many machines it may take several tries before a free address is found, so for performance purposes the successful address is "written down" in NVRAM
and used as the default address in the future. This means that in most real-world setups where machines are added a few at a time, only one or two tries are needed before the address effectively become constant.
-style reliable connection-oriented transport was needed. Significant differences from TCP were:
(AFP), formerly AppleTalk Filing Protocol, is the protocol for communicating with AppleShare
file servers. Built on top of AppleTalk Session Protocol (for legacy AFP over DDP) or the Data Stream Interface
(for AFP over TCP), it provides services for authenticating users (extensible to different authentication methods including two-way random-number exchange) and for performing operations specific to the Macintosh HFS
filesystem. AFP is still in use in Mac OS X, even though most other AppleTalk protocols have been deprecated.
An ATP request packet could be answered by up to eight response packets. The requestor then sent an acknowledgement packet containing a bit mask indicating which of the response packets it received, so the responder could retransmit the remainder.
ATP could operate in either "at-least-once" mode or "exactly-once" mode. Exactly-once mode was essential for operations which were not idempotent; in this mode, the responder kept a copy of the response buffers in memory until successful receipt of a release packet from the requestor, or until a timeout elapsed. This way, it could respond to duplicate requests with the same transaction ID by resending the same response data, without performing the actual operation again.**
service with no guarantees of delivery. All application-level protocols, including the infrastructure protocols NBP, RTMP and ZIP, were built on top of DDP.
Names were human readable, containing spaces, upper and lower case letters, and including support for searching.
printers. It was built on top of ATP. When a PAP connection was opened, each end sent the other an ATP request which basically meant "send me more data". The client's response to the server was to send a block of PostScript code, while the server could respond with any diagnostic messages that might be generated as a result, after which another "send-more-data" request was sent. This use of ATP provided automatic flow control
; each end could only send data to the other end if there was an outstanding ATP request to respond to.
PAP also provided for out-of-band status queries, handled by separate ATP transactions. Even while it was busy servicing a print job from one client, a PAP server could continue to respond to status requests from any number of other clients. This allowed other Macintoshes on the LAN that were waiting to print to display status messages indicating that the printer was busy, and what the job was that it was busy with.
that used the Macintosh's built-in RS-422 ports at 230.4 kbit/s. LocalTalk used a splitter box in the RS-422 port to provide an upstream and downstream cable from a single port. The topology was a bus
: cables were daisy-chained from each connected machine to the next, up to the maximum of 32 permitted on any LocalTalk
segment. The system was slow by today's standards, but at the time the additional cost and complexity of networking on PC machines was such that it was common that Macs were the only networked personal computers in an office. Other larger computers, such as UNIX or VAX workstations, would commonly be networked via Ethernet.
Other physical implementations were also available. One common replacement for LocalTalk was PhoneNet
, a 3rd party solution (from a company called Farallon, now called Netopia
) that also used the RS-422 port and was indistinguishable from LocalTalk as far as Apple's LocalTalk port drivers were concerned, but ran over the two unused wires in standard four-wire phone cabling. PhoneNet was considerably less expensive to install and maintain. Ethernet
and Token Ring was also supported, known as EtherTalk and TokenTalk respectively. EtherTalk in particular gradually became the dominant implementation method for AppleTalk as Ethernet became generally popular in the PC industry throughout the 1990s. Besides AppleTalk and TCP/IP, any Ethernet network could also simultaneously carry other protocols such as DECnet
, NetBEUI
, and IPX
.
The BSD and Linux
operating systems support AppleTalk through an open source project called Netatalk
, which implements the complete protocol suite and allows them to both act as native file or print servers for Macintosh computers, and print to LocalTalk printers over the network.
The Windows
Server operating systems supported AppleTalk starting with Windows NT
and ending after Windows Server 2003
. Miramar included AppleTalk in its PC MacLAN product which was discontinued by CA in 2007. Group Logic
continues to bundle its AppleTalk protocol with its ExtremeZ-IP
server software for Macintosh-Windows integration which supports Windows 2008 Server and Windows Vista
as well prior versions. HELIOS Software GmbH offers a proprietary implementation of the AppleTalk protocol stack, as part of their HELIOS UB2 server. This is essentially a File and Print Server suite that runs on a whole range of different platforms.
In addition, Columbia University released the Columbia AppleTalk Package (CAP) which implemented the protocol suite for various Unix flavors including Ultrix
, SunOS
, *BSD and IRIX
. This package is no longer actively maintained.
rules to allow Netatalk access
Proprietary protocol
In telecommunications, a proprietary protocol is a communications protocol owned by a single organization or individual.-Enforcement:Proprietors may enforce restrictions through patents and by keeping the protocol specification a trade secret...
suite of protocols
Protocol stack
The protocol stack is an implementation of a computer networking protocol suite. The terms are often used interchangeably. Strictly speaking, the suite is the definition of the protocols, and the stack is the software implementation of them....
developed by Apple Inc. for networking computers. It was included in the original Macintosh
Macintosh
The Macintosh , or Mac, is a series of several lines of personal computers designed, developed, and marketed by Apple Inc. The first Macintosh was introduced by Apple's then-chairman Steve Jobs on January 24, 1984; it was the first commercially successful personal computer to feature a mouse and a...
released in 1984, but is now unsupported as of the release of Mac OS X v10.6
Mac OS X v10.6
Mac OS X Snow Leopard is the seventh major release of Mac OS X, Apple's desktop and server operating system for Macintosh computers.Snow Leopard was publicly unveiled on June 8, 2009 at the Apple Worldwide Developers Conference...
in 2009 in favor of TCP/IP networking. AppleTalk's Datagram Delivery Protocol corresponds closely to the Network layer of the Open Systems Interconnection (OSI
OSI model
The Open Systems Interconnection model is a product of the Open Systems Interconnection effort at the International Organization for Standardization. It is a prescription of characterizing and standardizing the functions of a communications system in terms of abstraction layers. Similar...
) communication model.
Design
The AppleTalk design rigorously followed the OSI modelOSI model
The Open Systems Interconnection model is a product of the Open Systems Interconnection effort at the International Organization for Standardization. It is a prescription of characterizing and standardizing the functions of a communications system in terms of abstraction layers. Similar...
of protocol layering. Unlike most of the early LAN
Local area network
A local area network is a computer network that interconnects computers in a limited area such as a home, school, computer laboratory, or office building...
systems, AppleTalk was not built using the archetypal Xerox XNS system. The intended target was not Ethernet
Ethernet
Ethernet is a family of computer networking technologies for local area networks commercially introduced in 1980. Standardized in IEEE 802.3, Ethernet has largely replaced competing wired LAN technologies....
, and it did not have 48-bit addresses to route. Nevertheless, many portions of the AppleTalk system have direct analogs in XNS.
One key differentiation for AppleTalk was it contained three protocols aimed at making the system completely self-configuring. The AppleTalk address resolution protocol (AARP) allowed AppleTalk hosts to automatically generate their own network addresses, and the Name Binding Protocol (NBP) was a dynamic system for mapping network addresses to user-readable names. Although systems similar to AARP existed in other systems, Banyan VINES
Banyan VINES
Banyan VINES was a computer network operating system and the set of computer network protocols it used to talk to client machines on the network. The Banyan company based the VINES operating system on Unix, and the network protocols on the archetypical Xerox XNS stack...
for instance, nothing like NBP has existed until recently.
Both AARP and NBP had defined ways to allow "controller" devices to override the default mechanisms. The concept was to allow routers to provide the information or "hardwire" the system to known addresses and names. On larger networks where AARP could cause problems as new nodes searched for free addresses, the addition of a router could reduce "chattiness." Together AARP and NBP made AppleTalk an easy-to-use networking system. New machines were added to the network by plugging them and optionally giving them a name. The NBP lists were examined and displayed by a program known as the Chooser which would display a list of machines on the local network, divided into classes such as file-servers and printers.
History
AppleTalk was intended to be part of a project known as Macintosh OfficeMacintosh Office
The Macintosh Office was Apple's third failed attempt to enter into the business environment as a serious competitor to IBM. Consisting of three key parts, a network file server, local area network and a network Laser printer, Apple announced Macintosh Office in January 1985 with an ill-fated,...
, which would consist of a host machine providing routing, printer sharing and file sharing. However this project was canceled in 1986. Despite this, the LaserWriter
LaserWriter
The LaserWriter was a laser printer with built-in PostScript interpreter introduced by Apple in 1985. It was one of the first laser printers available to the mass market...
included built-in AppleTalk. Apple later released an AppleTalk server suite known as AppleShare
AppleShare
AppleShare was a product from Apple Computer which implemented various network services. Its main purpose was acting as a file server, using the AFP protocol...
, and included basic AppleTalk features as the default network protocol in later releases of "classic" Mac OS (System).
With the introduction of Mac OS X
Mac OS X
Mac OS X is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, has been included with all new Macintosh computer systems...
, AppleTalk was largely displaced. Internet-based
Internet protocol suite
The Internet protocol suite is the set of communications protocols used for the Internet and other similar networks. It is commonly known as TCP/IP from its most important protocols: Transmission Control Protocol and Internet Protocol , which were the first networking protocols defined in this...
protocols were used as the defaults, although AppleTalk was supported for backwards compatibility at first. Mac OS X v10.5
Mac OS X v10.5
Mac OS X Leopard is the sixth major release of Mac OS X, Apple's desktop and server operating system for Macintosh computers. Leopard was released on 26 October 2007 as the successor of Tiger , and is available in two variants: a desktop version suitable for personal computers, and a...
was the last Apple OS to support AppleTalk.
AppleTalk is largely based on the (unpatented) Cambridge Ring
Cambridge Ring
The Cambridge Ring was an experimental local area network architecture developed at the Cambridge University Computer Laboratory in the mid-late 1970s and early 1980s. It used a ring topology with a theoretical limit of 255 nodes , around which cycled a fixed number of packets...
.
Addressing
An AppleTalk address was a 4-byte quantity. This consisted of a two-byte network number, a one-byte node number, and a one-byte socket number. Of these, only the network number required any configuration, being obtained from a router. Each node dynamically chose its own node number, according to a protocol (originally the LocalTalk Link Access Protocol LLAP and later the AppleTalk Address Resolution Protocol, AARP) which handled contention between different nodes accidentally choosing the same number. For socket numbers, a few well-known numbers were reserved for special purposes specific to the AppleTalk protocol itself. Apart from these, all application-level protocols were expected to use dynamically-assigned socket numbers at both the client and server end.Because of this dynamism, users could not be expected to access services by specifying their address. Instead, all services had names which, being chosen by humans, could be expected to be meaningful to users, and also could be sufficiently long enough to minimize the chance of conflicts.
Note that, because a name translated to an address, which included a socket number as well as a node number, a name in AppleTalk mapped directly to a service being provided by a machine, which was entirely separate from the name of the machine itself. Thus, services could be moved to a different machine and, so long as they kept the same service name, there was no need for users to do anything different to continue accessing the service. And the same machine could host any number of instances of services of the same type, without any network connection conflicts.
Contrast this with A records in the DNS
Domain name system
The Domain Name System is a hierarchical distributed naming system for computers, services, or any resource connected to the Internet or a private network. It associates various information with domain names assigned to each of the participating entities...
, where a name translates only to a machine address, not including the port number that might be providing a service. Thus, if people are accustomed to using a particular machine name to access a particular service, their access will break when the service is moved to a different machine. This can be mitigated somewhat by insistence on using CNAME records indicating service rather than actual machine names to refer to the service, but there is no way of guaranteeing that users will follow such a convention. (Some newer protocols, such as Kerberos and Active Directory
Active Directory
Active Directory is a directory service created by Microsoft for Windows domain networks. It is included in most Windows Server operating systems. Server computers on which Active Directory is running are called domain controllers....
use DNS SRV record
SRV record
A Service record is a specification of data in the Domain Name System defining the location, i.e. the hostname and port number, of servers for specified services. It is defined in RFC 2782, and its type code is 33...
s to identify services by name, which is much closer to the AppleTalk model.)
AppleTalk Address Resolution Protocol
AARP resolves AppleTalk addresses to link layerLink Layer
In computer networking, the link layer is the lowest layer in the Internet Protocol Suite , the networking architecture of the Internet . It is the group of methods or protocols that only operate on a host's link...
, usually MAC
MAC address
A Media Access Control address is a unique identifier assigned to network interfaces for communications on the physical network segment. MAC addresses are used for numerous network technologies and most IEEE 802 network technologies, including Ethernet...
, addresses. It is functionally equivalent to ARP
Address Resolution Protocol
Address Resolution Protocol is a telecommunications protocol used for resolution of network layer addresses into link layer addresses, a critical function in multiple-access networks. ARP was defined by RFC 826 in 1982. It is Internet Standard STD 37...
.
AARP is a fairly simple system. When powered on, an AppleTalk machine broadcasts an AARP probe packet asking for a network address, intending to hear back from controllers such as routers. If no address is provided, one is picked at random from the "base subnet", 0. It then broadcasts another packet saying "I am selecting this address", and then waits to see if anyone else on the network complains. If another machine has that address, it will pick another address, and keep trying until it finds a free one. On a network with many machines it may take several tries before a free address is found, so for performance purposes the successful address is "written down" in NVRAM
NVRAM
Non-volatile random-access memory is random-access memory that retains its information when power is turned off, which is described technically as being non-volatile...
and used as the default address in the future. This means that in most real-world setups where machines are added a few at a time, only one or two tries are needed before the address effectively become constant.
AppleTalk Data Stream Protocol
This was a comparatively late addition to the AppleTalk protocol suite, done when it became clear that a TCPTransmission Control Protocol
The Transmission Control Protocol is one of the core protocols of the Internet Protocol Suite. TCP is one of the two original components of the suite, complementing the Internet Protocol , and therefore the entire suite is commonly referred to as TCP/IP...
-style reliable connection-oriented transport was needed. Significant differences from TCP were:
- a connection attempt could be rejected
- there were no "half-open" connections; once one end initiated a tear-down of the connection, the whole connection would be closed (i.e., ADSP is full-duplexDuplex (telecommunications)A duplex communication system is a system composed of two connected parties or devices that can communicate with one another in both directions. The term multiplexing is used when describing communication between more than two parties or devices....
, not dual simplex).
Apple Filing Protocol
The Apple Filing ProtocolApple Filing Protocol
The Apple Filing Protocol is a network protocol that offers file services for Mac OS X and original Mac OS. In Mac OS X, AFP is one of several file services supported including Server Message Block , Network File System , File Transfer Protocol , and WebDAV...
(AFP), formerly AppleTalk Filing Protocol, is the protocol for communicating with AppleShare
AppleShare
AppleShare was a product from Apple Computer which implemented various network services. Its main purpose was acting as a file server, using the AFP protocol...
file servers. Built on top of AppleTalk Session Protocol (for legacy AFP over DDP) or the Data Stream Interface
Data Stream Interface
The Data Stream Interface is a session layer used to carry Apple Filing Protocol traffic over Transmission Control Protocol.- Overview :...
(for AFP over TCP), it provides services for authenticating users (extensible to different authentication methods including two-way random-number exchange) and for performing operations specific to the Macintosh HFS
Hierarchical File System
Hierarchical File System is a file system developed by Apple Inc. for use in computer systems running Mac OS. Originally designed for use on floppy and hard disks, it can also be found on read-only media such as CD-ROMs...
filesystem. AFP is still in use in Mac OS X, even though most other AppleTalk protocols have been deprecated.
AppleTalk Session Protocol
ASP was an intermediate protocol, built on top of ATP, which in turn was the foundation of AFP. It provided basic services for requesting responses to arbitrary commands and performing out-of-band status queries. It also allowed the server to send asynchronous attention messages to the client.AppleTalk Transaction Protocol
ATP was the original reliable transport-level protocol for AppleTalk, built on top of DDP. At the time it was being developed, a full, reliable connection-oriented protocol like TCP was considered to be too expensive to implement for most of the intended uses of AppleTalk. Thus, ATP was a simple request/response exchange, with no need to set up or tear down connections.An ATP request packet could be answered by up to eight response packets. The requestor then sent an acknowledgement packet containing a bit mask indicating which of the response packets it received, so the responder could retransmit the remainder.
ATP could operate in either "at-least-once" mode or "exactly-once" mode. Exactly-once mode was essential for operations which were not idempotent; in this mode, the responder kept a copy of the response buffers in memory until successful receipt of a release packet from the requestor, or until a timeout elapsed. This way, it could respond to duplicate requests with the same transaction ID by resending the same response data, without performing the actual operation again.**
Datagram Delivery Protocol
DDP was the lowest-level data-link-independent transport protocol. It provided a datagramDatagram
A datagram is a basic transfer unit associated with a packet-switched network in which the delivery, arrival time, and order are not guaranteed....
service with no guarantees of delivery. All application-level protocols, including the infrastructure protocols NBP, RTMP and ZIP, were built on top of DDP.
Name Binding Protocol
NBP was a dynamic, distributed system for managing AppleTalk names. When a service started up on a machine, it registered a name for itself on that machine, as chosen by a human administrator. At this point, NBP provided a system for checking that no other machine had already registered the same name. Then later, when a client wanted to access that service, it used NBP to query machines to find that service. NBP provided browseability ("what are the names of all the services available?") as well as the ability to find a service with a particular name.Names were human readable, containing spaces, upper and lower case letters, and including support for searching.
Printer Access Protocol
PAP was the standard way of communicating with PostScriptPostScript
PostScript is a dynamically typed concatenative programming language created by John Warnock and Charles Geschke in 1982. It is best known for its use as a page description language in the electronic and desktop publishing areas. Adobe PostScript 3 is also the worldwide printing and imaging...
printers. It was built on top of ATP. When a PAP connection was opened, each end sent the other an ATP request which basically meant "send me more data". The client's response to the server was to send a block of PostScript code, while the server could respond with any diagnostic messages that might be generated as a result, after which another "send-more-data" request was sent. This use of ATP provided automatic flow control
Flow control
In data communications, flow control is the process of managing the pacing of data transmission between two nodes to prevent a fast sender from outrunning a slow receiver. It provides a mechanism for the receiver to control the transmission speed, so that the receiving node is not overwhelmed with...
; each end could only send data to the other end if there was an outstanding ATP request to respond to.
PAP also provided for out-of-band status queries, handled by separate ATP transactions. Even while it was busy servicing a print job from one client, a PAP server could continue to respond to status requests from any number of other clients. This allowed other Macintoshes on the LAN that were waiting to print to display status messages indicating that the printer was busy, and what the job was that it was busy with.
Routing Table Maintenance Protocol
RTMP was the protocol by which routers kept each other informed about the topology of the network. This was the only part of AppleTalk that required periodic unsolicited broadcasts: every 10 seconds, each router had to send out a list of all the network numbers it knew about and how far away it thought they were.Zone Information Protocol
ZIP was the protocol by which AppleTalk network numbers were associated with zone names. A zone was a subdivision of the network that made sense to humans (for example, "Accounting Department"); but while a network number had to be assigned to a topologically-contiguous section of the network, a zone could include several different discontiguous portions of the network.Physical implementation
The initial default hardware implementation for AppleTalk was a high-speed serial protocol known as LocalTalkLocalTalk
LocalTalk is a particular implementation of the physical layer of the AppleTalk networking system from Apple Computer. LocalTalk specifies a system of shielded twisted pair cabling, plugged into self-terminating transceivers, running at a rate of 230.4 kbit/s...
that used the Macintosh's built-in RS-422 ports at 230.4 kbit/s. LocalTalk used a splitter box in the RS-422 port to provide an upstream and downstream cable from a single port. The topology was a bus
Bus network
A bus network topology is a network architecture in which a set of clients are connected via a shared communications line, called a bus. There are several common instances of the bus architecture, including one in the motherboard of most computers, and those in some versions of Ethernet...
: cables were daisy-chained from each connected machine to the next, up to the maximum of 32 permitted on any LocalTalk
LocalTalk
LocalTalk is a particular implementation of the physical layer of the AppleTalk networking system from Apple Computer. LocalTalk specifies a system of shielded twisted pair cabling, plugged into self-terminating transceivers, running at a rate of 230.4 kbit/s...
segment. The system was slow by today's standards, but at the time the additional cost and complexity of networking on PC machines was such that it was common that Macs were the only networked personal computers in an office. Other larger computers, such as UNIX or VAX workstations, would commonly be networked via Ethernet.
Other physical implementations were also available. One common replacement for LocalTalk was PhoneNet
PhoneNet
PhoneNet was an implementation of the AppleTalk networking physical layer created by Farallon Computing . Instead of using expensive shielded twisted pair wiring as in Apple's LocalTalk implementation, PhoneNet uses standard four-conductor telephone patch cords and modular connectors, and is...
, a 3rd party solution (from a company called Farallon, now called Netopia
Netopia
Netopia is a company, headquartered in Emeryville, California, that produces a variety of broadband products including modems, routers, gateways, and Wi-Fi devices. The company also produces the NBBS , as well as the Timbuktu remote administration software...
) that also used the RS-422 port and was indistinguishable from LocalTalk as far as Apple's LocalTalk port drivers were concerned, but ran over the two unused wires in standard four-wire phone cabling. PhoneNet was considerably less expensive to install and maintain. Ethernet
Ethernet
Ethernet is a family of computer networking technologies for local area networks commercially introduced in 1980. Standardized in IEEE 802.3, Ethernet has largely replaced competing wired LAN technologies....
and Token Ring was also supported, known as EtherTalk and TokenTalk respectively. EtherTalk in particular gradually became the dominant implementation method for AppleTalk as Ethernet became generally popular in the PC industry throughout the 1990s. Besides AppleTalk and TCP/IP, any Ethernet network could also simultaneously carry other protocols such as DECnet
DECnet
DECnet is a suite of network protocols created by Digital Equipment Corporation, originally released in 1975 in order to connect two PDP-11 minicomputers. It evolved into one of the first peer-to-peer network architectures, thus transforming DEC into a networking powerhouse in the 1980s...
, NetBEUI
NetBEUI
NetBIOS Frames or NBF protocol is a non-routable network- and transport-level data protocol most commonly used as one of the layers of Microsoft Windows networking in the 1990s. NBF protocol or NetBIOS over IEEE 802.2 LLC is used by a number of network operating systems released in the 1990s, such...
, and IPX
IPX
Internetwork Packet Exchange is the OSI-model Network layer protocol in the IPX/SPX protocol stack.The IPX/SPXM protocol stack is supported by Novell's NetWare network operating system. Because of Netware's popularity through the late 1980s into the mid 1990s, IPX became a popular internetworking...
.
Networking model
| OSI Model | Corresponding AppleTalk layers |
|---|---|
| Application Application layer The Internet protocol suite and the Open Systems Interconnection model of computer networking each specify a group of protocols and methods identified by the name application layer.... |
Apple Filing Protocol Apple Filing Protocol The Apple Filing Protocol is a network protocol that offers file services for Mac OS X and original Mac OS. In Mac OS X, AFP is one of several file services supported including Server Message Block , Network File System , File Transfer Protocol , and WebDAV... (AFP) |
| Presentation Presentation layer The presentation layer is layer 6 of the seven-layer OSI model of computer networking and serves as the data translator for the network. It is sometimes called the syntax layer.-Description:... |
Apple Filing Protocol Apple Filing Protocol The Apple Filing Protocol is a network protocol that offers file services for Mac OS X and original Mac OS. In Mac OS X, AFP is one of several file services supported including Server Message Block , Network File System , File Transfer Protocol , and WebDAV... (AFP) |
| Session Session layer The session layer is layer 5 of the seven-layer OSI model of computer networking.The session layer provides the mechanism for opening, closing and managing a session between end-user application processes, i.e., a semi-permanent dialogue. Communication sessions consist of requests and responses... |
Zone Information Protocol (ZIP) AppleTalk Session Protocol (ASP) AppleTalk Data Stream Protocol (ADSP) |
| Transport Transport layer In computer networking, the transport layer or layer 4 provides end-to-end communication services for applications within a layered architecture of network components and protocols... |
AppleTalk Transaction Protocol (ATP) AppleTalk Echo Protocol AppleTalk Echo Protocol AEP is a transport layer protocol in the AppleTalk protocol suite designed to test the reachability of network nodes. AEP generates packets to be sent to the network node and is identified in the Type field of a packet as an AEP packet. The packet is first passed to the source DDP... (AEP) Name Binding Protocol (NBP) Routing Table Maintenance Protocol (RTMP) |
| Network Network layer The network layer is layer 3 of the seven-layer OSI model of computer networking.The network layer is responsible for packet forwarding including routing through intermediate routers, whereas the data link layer is responsible for media access control, flow control and error checking.The network... |
Datagram Delivery Protocol (DDP Datagram Delivery Protocol Datagram Delivery Protocol is a member of the AppleTalk networking protocol suite. Its main responsibility is for socket-to-socket delivery of datagrams over an AppleTalk network.... ) |
| Data link Data link layer The data link layer is layer 2 of the seven-layer OSI model of computer networking. It corresponds to, or is part of the link layer of the TCP/IP reference model.... |
EtherTalk Link Access Protocol (ELAP) LocalTalk Link Access Protocol (LLAP) TokenTalk Link Access Protocol (TLAP) Fiber Distributed Data Interface (FDDI) |
| Physical Physical layer The physical layer or layer 1 is the first and lowest layer in the seven-layer OSI model of computer networking. The implementation of this layer is often termed PHY.... |
LocalTalk LocalTalk LocalTalk is a particular implementation of the physical layer of the AppleTalk networking system from Apple Computer. LocalTalk specifies a system of shielded twisted pair cabling, plugged into self-terminating transceivers, running at a rate of 230.4 kbit/s... driver Ethernet Ethernet Ethernet is a family of computer networking technologies for local area networks commercially introduced in 1980. Standardized in IEEE 802.3, Ethernet has largely replaced competing wired LAN technologies.... driver Token Ring IBM token ring thumb|Two examples of token ring networks: a) Using a single [[Media Access Unit|MAU]] b) Using several MAUs connected to each otherthumb|Token ring networkthumb|IBM hermaphroditic connector with locking clipthumb|An IBM 8228 MAU... driver FDDI driver |
Versions
| AppleTalk version | Apple Filing Protocol Apple Filing Protocol The Apple Filing Protocol is a network protocol that offers file services for Mac OS X and original Mac OS. In Mac OS X, AFP is one of several file services supported including Server Message Block , Network File System , File Transfer Protocol , and WebDAV... |
Corresponds to | Notes |
|---|---|---|---|
| 56 | System 7.0 | ||
| 57.0.4 | System 7.12 | ||
| 58.1.1 | System 7.1.2 | ||
| 58.1.3 | System 7.5 | ||
| 60.3 | Mac OS 7.6.1 | Open Transport 1.3 | |
| 60.0a6 | Mac OS 8.6 | Open Transport 2.0.3 | |
| 3.0 | Mac OS X 10.0.3 | ||
| 3.1 | Mac OS X v10.3 Mac OS X v10.3 Mac OS X Panther is the fourth major release of Mac OS X, Apple’s desktop and server operating system. It followed Mac OS X v10.2 "Jaguar" and preceded Mac OS X Tiger... |
||
| 3.2 | Mac OS X v10.4 Mac OS X v10.4 Mac OS X v10.4 Tiger is the fifth major release of Mac OS X, Apple's desktop and server operating system for Macintosh computers. Tiger was released to the public on 29 April 2005 for US$129.95 as the successor to Mac OS X Panther , which had been released 18 months earlier... |
Cross-platform solutions
When AppleTalk was first introduced the dominant office computing platform was the PC compatible running MS-DOS. The "TOPS Teleconnector" system enabled MS-DOS PCs to communicate over AppleTalk network hardware; it comprised an AppleTalk interface card for the PC and a suite of networking software allowing such functions as file, drive and printer sharing. As well as allowing the construction of a PC-only AppleTalk network, it allowed communication between PCs and Macs with TOPS software installed. (Macs without TOPS installed could use the same network but only to communicate with other Apple machines.) The Mac TOPS software did not match the quality of Apple's own either in ease of use or in robustness and freedom from crashes, but the DOS software was relatively simple to use in DOS terms, and was robust.The BSD and Linux
Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...
operating systems support AppleTalk through an open source project called Netatalk
Netatalk
Netatalk is a free, open-source implementation of the AppleTalk suite of protocols. It allows Unix-like operating systems to serve as file, print and time servers for Macintosh computers....
, which implements the complete protocol suite and allows them to both act as native file or print servers for Macintosh computers, and print to LocalTalk printers over the network.
The Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
Server operating systems supported AppleTalk starting with Windows NT
Windows NT
Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. It was a powerful high-level-language-based, processor-independent, multiprocessing, multiuser operating system with features comparable to Unix. It was intended to complement...
and ending after Windows Server 2003
Windows Server 2003
Windows Server 2003 is a server operating system produced by Microsoft, introduced on 24 April 2003. An updated version, Windows Server 2003 R2, was released to manufacturing on 6 December 2005...
. Miramar included AppleTalk in its PC MacLAN product which was discontinued by CA in 2007. Group Logic
Group Logic
, founded in 1988 and headquartered in Arlington, VA, USA, is an enterprise software company that develops, sells and supports software for moving and storing data including mobilEcho, , MassTransit and ExtremeZ-IP...
continues to bundle its AppleTalk protocol with its ExtremeZ-IP
ExtremeZ-IP
ExtremeZ-IP, a Apple Filing Protocol server from Group Logic, Inc, , runs on Windows operating systems enabling Mac clients to access files via the Apple Filing protocol...
server software for Macintosh-Windows integration which supports Windows 2008 Server and Windows Vista
Windows Vista
Windows Vista is an operating system released in several variations developed by Microsoft for use on personal computers, including home and business desktops, laptops, tablet PCs, and media center PCs...
as well prior versions. HELIOS Software GmbH offers a proprietary implementation of the AppleTalk protocol stack, as part of their HELIOS UB2 server. This is essentially a File and Print Server suite that runs on a whole range of different platforms.
In addition, Columbia University released the Columbia AppleTalk Package (CAP) which implemented the protocol suite for various Unix flavors including Ultrix
Ultrix
Ultrix was the brand name of Digital Equipment Corporation's native Unix systems. While ultrix is the Latin word for avenger, the name was chosen solely for its sound.-History:...
, SunOS
SunOS
SunOS is a version of the Unix operating system developed by Sun Microsystems for their workstation and server computer systems. The SunOS name is usually only used to refer to versions 1.0 to 4.1.4 of SunOS...
, *BSD and IRIX
IRIX
IRIX is a computer operating system developed by Silicon Graphics, Inc. to run natively on their 32- and 64-bit MIPS architecture workstations and servers. It was based on UNIX System V with BSD extensions. IRIX was the first operating system to include the XFS file system.The last major version...
. This package is no longer actively maintained.
Ports Used
Sample iptablesIptables
iptables is a user space application program that allows a system administrator to configure the tables provided by the Linux kernel firewall and the chains and rules it stores...
rules to allow Netatalk access
- Netatalk needs a flock of ports.
- This is the one-line-per-port example, and should work with
- older versions of iptables.
-A UVAfw -s 128.143.0.0/16 -p tcp --dport 427 -j ACCEPT
-A UVAfw -s 128.143.0.0/16 -p udp --dport 427 -j ACCEPT
-A UVAfw -s 128.143.0.0/16 -p tcp --dport 548 -j ACCEPT
-A UVAfw -s 128.143.0.0/16 -p tcp --dport 201 -j ACCEPT
-A UVAfw -s 128.143.0.0/16 -p tcp --dport 202 -j ACCEPT
-A UVAfw -s 128.143.0.0/16 -p tcp --dport 204 -j ACCEPT
-A UVAfw -s 128.143.0.0/16 -p tcp --dport 206 -j ACCEPT
- -A UVAfw -s 137.54.0.0/16 -p tcp --dport 427 -j ACCEPT
- -A UVAfw -s 137.54.0.0/16 -p udp --dport 427 -j ACCEPT
- -A UVAfw -s 137.54.0.0/16 -p tcp --dport 548 -j ACCEPT
- -A UVAfw -s 137.54.0.0/16 -p tcp --dport 201 -j ACCEPT
- -A UVAfw -s 137.54.0.0/16 -p tcp --dport 202 -j ACCEPT
- -A UVAfw -s 137.54.0.0/16 -p tcp --dport 204 -j ACCEPT
- -A UVAfw -s 137.54.0.0/16 -p tcp --dport 206 -j ACCEPT
- Multiport variant of the netatalk ports above.
- I'm not quite sure why 427 is missing.
-A UVAfw -m multiport -s 128.143.0.0/16 -p tcp --dports 548,201,202,204,206 -j ACCEPT
See also
- Cambridge RingCambridge RingThe Cambridge Ring was an experimental local area network architecture developed at the Cambridge University Computer Laboratory in the mid-late 1970s and early 1980s. It used a ring topology with a theoretical limit of 255 nodes , around which cycled a fixed number of packets...
- NetatalkNetatalkNetatalk is a free, open-source implementation of the AppleTalk suite of protocols. It allows Unix-like operating systems to serve as file, print and time servers for Macintosh computers....
is a free, open-source implementation of the AppleTalk suite of protocols. - Network File System
- Remote File SystemRemote File SystemThe Remote File System was a distributed file system developed by AT&T in the 1980s. It was first delivered with UNIX System V Release 3 .Compared to NFS it made quite different design decisions...
- Samba
- Server Message BlockServer Message BlockIn computer networking, Server Message Block , also known as Common Internet File System operates as an application-layer network protocol mainly used to provide shared access to files, printers, serial ports, and miscellaneous communications between nodes on a network. It also provides an...