AppleTalk facts for kids

Quick facts for kids
AppleTalk

Protocol stack
Developer(s)	Apple Computer
Introduction	1985; 40 years ago (1985)
Hardware	LocalTalk, others

AppleTalk was a special set of rules, called a protocol suite, created by Apple Computer for their Macintosh computers. It helped these computers connect and share information in a local area network (LAN). Think of it like a language computers use to talk to each other.

One cool thing about AppleTalk was that it was super easy to set up. You didn't need a special expert or a central server. Computers using AppleTalk could automatically find each other, get their own network addresses, and even help route information. It was truly "plug-and-play."

Apple released AppleTalk in 1985. It was the main way Apple devices connected throughout the 1980s and 1990s. You could even find versions for IBM PCs and Apple IIGS computers. Many printers, especially laser printers, and some file servers also supported AppleTalk.

However, in the 1990s, another set of rules called TCP/IP became very popular. This is the main language the internet uses today. Because of this, Apple slowly stopped supporting AppleTalk. By 2009, with the release of Mac OS X v10.6, AppleTalk was no longer supported. Many of AppleTalk's easy setup features are now found in newer technologies like Bonjour.

History

Early Network Ideas

After Apple released the Apple Lisa computer in 1983, they worked hard on a network system called AppleNet. This system was meant to connect computers in a local area. It was based on a system from Xerox, but Apple used its own special cables. AppleNet was announced in 1983, but it was later canceled.

At that time, many different network systems were competing, like Ethernet and Token Ring. Apple decided it was better to support existing standards rather than create their own.

AppleBus and Easy Connections

While developing the Macintosh, Apple engineers chose a special chip called the Zilog SCC for the computer's serial ports. This chip was a bit more expensive but allowed for faster connections and could handle multiple devices. The idea was to connect many devices to one port, reducing the need for lots of different ports or expansion cards. This early idea was called AppleBus.

The Macintosh team also wanted to make it easy to share expensive devices like the LaserWriter printer. They realized that IBM's Token Ring network wouldn't be ready in time for the Mac's launch. So, they started working on a new network system based on the AppleBus hardware.

This new system was designed to be super simple for users. You could just plug it in, and it would work without needing complicated settings or fixed network addresses. It was a true "plug-and-play" network. This "new" AppleBus was announced in 1984.

AppleTalk Personal Network

Just before its release in early 1985, AppleBus was renamed AppleTalk. It was first called AppleTalk Personal Network. It included both the network rules (protocols) and the physical way devices connected.

The first physical connection, later called LocalTalk, was a bit slow (230.4 kilobits per second) and could only connect up to 32 devices over a distance of about 1000 feet (300 meters). But since the basic parts were already built into the Mac, adding a device only cost about $50 for a small adapter box. This was much cheaper than Ethernet or Token Ring cards, which cost hundreds or thousands of dollars. The entire AppleTalk system also used very little computer memory, so it could run on any Mac.

AppleTalk was designed to be easy to expand. It could handle up to 255 devices on a network, and you could connect different networks using "bridges" (which we now call "routers"). These connected networks could be organized into "zones" to make them easier to manage.

The biggest advantage of AppleTalk was how easy it was to use. To connect a device, you just plugged in an adapter and connected a cable. The network would automatically give the computer an address, a name, and show you a list of other devices. This made it very popular, and Apple even showed it in an advertisement where a network was created between two seats on an airplane!

PhoneNet and Other Adapters

Because AppleTalk was slow but cheap, it became very popular. Other companies started making their own AppleTalk devices. One famous example was PhoneNET from Farallon. This adapter let you use regular telephone wires to connect AppleTalk networks. You could even use the same phone cable for both your phone and your network!

Some companies also made faster AppleTalk systems, like FlashTalk and DaynaTalk, which could reach speeds up to 1 Mbit/s.

AppleTalk Over Ethernet

As Apple computers became more common in businesses and schools, they needed to connect to existing networks, especially Ethernet. AppleTalk had a way to connect different AppleTalk networks together. So, EtherTalk was created to use Ethernet as a main connection between LocalTalk networks. Companies like Hayes and Kinetics made special "LocalTalk-to-Ethernet bridges" to help with this.

LocalTalk, EtherTalk, TokenTalk, and AppleShare

By 1987, Ethernet was becoming the most popular network standard. Apple introduced EtherTalk 1.0, which allowed AppleTalk to run directly over Ethernet. This was for the new Macintosh II computer, which had expansion slots. Users could choose which connection to use in their computer settings. With EtherTalk, the original AppleTalk Personal Network was renamed LocalTalk. Later, Apple also supported Token Ring networks with a similar product called TokenTalk.

Many networks had both new Macs with Ethernet and older Macs with LocalTalk. To help them communicate, Apple relied on those LocalTalk-to-Ethernet bridges. By the end of 1987, AppleTalk was one of the most used network systems in the world.

In 1987, Apple also released AppleShare, a special program that turned any Mac into a file server. This allowed users to share files easily. AppleShare became very popular for sharing files on Mac networks.

AppleTalk Phase II and Later

In 1989, Apple released a big update called AppleTalk Phase II. This version made the system more flexible. Networks could now have more than 255 devices, and "zones" (groups of devices) could be set up in any way, not just based on physical location. Phase II also made the network less "chatty," which helped when connecting networks over long distances.

Apple also started building Ethernet directly into Macs. They created a special port called AAUI (Apple AUI) that allowed users to plug in different adapters for various Ethernet cables. Later, Macs started including the more common 10BASE-T Ethernet port.

The Internet and AppleTalk's End

In the early 1990s, people wanted to connect their Macs to the growing TCP/IP networks. Programs like MacIP allowed AppleTalk networks to carry Internet traffic. By 1994, MacTCP, which allowed Macs to use TCP/IP, became a standard part of the Mac operating system.

As the world moved to TCP/IP for all networking, AppleTalk became an older system. When Apple created Mac OS X, AppleTalk was kept for a while to support old printers and file shares. However, as new ways to connect devices (like USB for printers) became popular, AppleTalk was used less and less. Finally, Apple removed AppleTalk support from macOS in 2009.

Even though AppleTalk is gone, its idea of easy-to-use networking lives on. Apple has developed new technologies like AirPort routers and Bonjour (which helps devices find each other automatically on a network) that offer similar benefits using modern IP networks.

As of 2020, AppleTalk support has been completely removed from macOS.

How AppleTalk Worked

AppleTalk was designed very carefully, following a model called the OSI model. This model breaks down how networks work into different layers.

One of the coolest things about AppleTalk was that it could set itself up automatically.

• The AppleTalk Address Resolution Protocol (AARP) helped devices automatically get their own network addresses.
• The Name Binding Protocol (NBP) let users give easy-to-remember names to devices and services, like "My Printer" or "Shared Files."

When you turned on an AppleTalk device, AARP would help it find a free address. If no router gave it an address, it would pick one randomly and check if anyone else was using it. Once it had an address, NBP would let you give it a name.

These features made AppleTalk super easy to use. You just plugged in a new machine, maybe gave it a name, and it would show up on the network. A program called the Chooser on the Mac would show you a list of all the devices, like printers and file servers, making it simple to find what you needed.

Addressing and Naming

An AppleTalk address had four parts: a network number, a device number, and a socket number. Only the network number usually came from a router. Each device chose its own device number, and the system made sure no two devices had the same one.

Because addresses could change, users didn't have to remember complicated numbers. Instead, all services had names that humans chose, like "Office Printer" or "Design Server." These names could be long and include spaces, making them easy to understand.

A name in AppleTalk pointed directly to a service on a machine, not just the machine itself. This meant if a service (like a printer) moved to a different computer, its name could stay the same, and users wouldn't even notice the change. This is different from how some other networks work, where a name usually points to a computer's address.

Key Protocols

AppleTalk Address Resolution Protocol (AARP)

AARP helps AppleTalk devices find their network addresses. When a device starts, it asks for an address. If it doesn't get one, it picks a random address and checks if anyone else is using it. If the address is free, it uses it. This makes setting up new devices very simple.

AppleTalk Data Stream Protocol (ADSP)

ADSP was added later to provide a reliable way for two devices to send data back and forth, similar to how TCP works on the internet. It made sure that data arrived in the correct order and that nothing was lost.

Apple Filing Protocol (AFP)

Apple Filing Protocol (AFP) is the set of rules for talking to AppleShare file servers. It helps users log in and lets them work with files and folders on the server. AFP is still used in modern macOS versions for file sharing, even though most other AppleTalk protocols are no longer used.

AppleTalk Session Protocol (ASP)

ASP was a protocol that helped manage communication sessions. It was built on top of ATP and allowed devices to send commands and get status updates.

AppleTalk Transaction Protocol (ATP)

ATP was an early reliable way to send data in AppleTalk. It was simpler than a full connection-based protocol. When one device sent a request, the other could send up to eight response packets. The first device would then confirm which packets it received, and the sender would resend any missing ones.

Datagram Delivery Protocol (DDP)

DDP was the most basic way to send data in AppleTalk. It sent data in small packages called datagrams, but it didn't guarantee that they would arrive. All other AppleTalk protocols were built on top of DDP.

Name Binding Protocol (NBP)

NBP was a smart system for managing AppleTalk names. When a service started, it registered a name. NBP made sure no other device had the same name. When a user wanted to find a service, NBP helped them search for it by name. This made it easy to browse and find devices on the network.

AppleTalk Echo Protocol (AEP)

AEP was used to test if a network device was reachable. It sent a small packet to a device, and if the device was there, it would send the packet back. This was like a "ping" to see if a device was online.

Printer Access Protocol (PAP)

PAP was the standard way to talk to PostScript printers. It was built on ATP. When you printed something, PAP would send the print job to the printer. It also allowed other computers to check the printer's status, so they could see if it was busy.

Routing Table Maintenance Protocol (RTMP)

RTMP was how AppleTalk routers shared information about the network. Every 10 seconds, routers would send out a list of all the network numbers they knew about and how far away they were.

Zone Information Protocol (ZIP)

ZIP connected AppleTalk network numbers with "zone" names. A zone was a way to group parts of the network that made sense to people, like "Accounting Department." A zone could include different parts of the network, even if they weren't physically connected.

Physical Connections

The first way AppleTalk connected devices was through a system called LocalTalk. It used the Macintosh's built-in serial ports and special cables. You would daisy-chain cables from one computer to the next. LocalTalk was slow, but it was cheap and easy to set up, especially when other computers needed expensive network cards.

Farallon PhoneNET adapter

A very popular alternative to LocalTalk was PhoneNET from Farallon. It also used the Mac's serial port but ran over very inexpensive standard phone cables. This meant you could use existing phone wires to connect your network. PhoneNet was cheap, flexible, and easy to fix if there was a problem, making it very popular for Mac networks.

Later, AppleTalk protocols also ran over Ethernet and Token Ring physical connections. These were called EtherTalk and TokenTalk. EtherTalk became the most common way to use AppleTalk as Ethernet became popular in the computer world.

Versions of AppleTalk

AppleTalk on Other Computers

In the late 1980s, Apple made it possible for Windows PCs to join AppleTalk networks. They released the AppleTalk PC Card in 1987, allowing PCs to print to LaserWriter printers. A year later, AppleShare PC let PCs access AppleShare file servers.

Today, open-source projects like Netatalk allow BSD and Linux computers to use AppleTalk. This means they can act as file or print servers for older Macintosh computers.

Windows Server operating systems also supported AppleTalk for a while, starting with Windows NT and ending after Windows Server 2003. Some companies still offer software that includes AppleTalk for connecting Macs and Windows computers.

Images for kids

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  Interior of Apple LocalTalk interface box.

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  Rear view of auto-termination switch with dust cover removed

See also

In Spanish: AppleTalk para niños

• Netatalk is a free, open-source way to use AppleTalk protocols.
• Network File System
• Remote File Sharing
• Samba
• Server Message Block