AppleTalk is Apple Computer’s LAN protocol. It is built into every Macintosh computer and facilitates communications between a variety of Apple and non-Apple products linked on LANs. AppleTalk provides access to print and file servers, e-mail applications, and other network services. The AppleTalk network itself can be configured in either a bus, star, or ring topology.
When AppleTalk is used among Macintosh computers in a small workgroup LAN the physical connection is called LocalTalk. It lets Macintosh computers in any network configuration communicate among themselves or with a printer at 230.4 Kbps over unshielded twisted pair (UTP) wiring or a RJ-11 phone cable (i.e., PhoneNet). Although LocalTalk networks are relatively slow, they are popular because they are easy and inexpensive to install and maintain. Up to 32 nodes are supported on a LocalTalk network.
AppleTalk can also be run over other types of higher-speed networks. When AppleTalk runs over Ethernet, token ring, and FDDI, the networks are referred to as EtherTalk, TokenTalk, and FDDITalk, respectively. AppleTalk networks can be interconnected through routers. An AppleTalk internet can consist of a mix of LocalTalk, TokenTalk, EtherTalk, and FDDITalk networks, or it can consist of more than one network of a single type, such as several LocalTalk networks.
AppleTalk can also be carried within different protocols through a process known as encapsulation or tunneling. This would allow two Macintosh computers to communicate through a TCP/IP-based Virtual Private Network (VPN), for example, using various tunneling protocols.
Other Connectivity Options
Additional Apple software may be required to connect computers to a network or implement special features, such as:
APPLETALK REMOTE ACCESS A family of products that allows individuals or workgroups to access information and services remotely over a variety of connections, ranging from telephone lines to wireless links over cellular networks.
APPLE INTERNET ROUTER Allows users to increase the size, performance, and manageability of their AppleTalk networks. Features include the isolation of local traffic, built-in data compression for maximizing throughput, Macintosh-based administration and configuration, and administrator password options to lock out unauthorized access.
APPLESEARCH Turns a collection of documents stored on a server into an online library where users can research a variety of information. Apple- Search recognizes and processes natural-language search queries, as well as the Boolean queries. In addition, it uses a relevance-ranking algorithm to present the most useful references first. The documents are not altered; instead, they are stored in their native format and translated into searchable text by Apple’s XTND technology.
APPLESHARE Provides file and print services, centralized storage, and administration capabilities to users in a workgroup or department.
APPLESHARE IP Combines traditional file sharing using TCP/IP and AppleTalk, with File Transfer Protocol (FTP) capabilities, a POP3/SMTP mail server, an HTTP Web server, and an AppleTalk print server to provide users with a one-stop productivity solution for shared information and resources.
MACX.400 Turns a Macintosh computer into a Message Transfer Agent (MTA) that supports the X.400 messaging standards. It allows e-mail and other electronic documents to be sent from a Macintosh computer to any number of users who work on other computer platforms and use other email systems. This can be accomplished over the Internet and through a variety of network environments.
MACX High-performance software that enables users to seamlessly run both network-based X applications and Mac OS applications on one Macintosh computer. It delivers the rich application and development resources of network-based UNIX and VMS systems with the productivity and ease of use of the Mac OS.
MACX25 MacX25 server software allows users to link Macintosh computers to X.25 packet data networks. It can also be used with the Apple Internet Router to connect remote AppleTalk networks over X.25 links. Using this server software, a Macintosh can be set up as a gateway to an X.25 network. The MacX25 server distributes access to host computers and end-user services to Macintosh computers over the AppleTalk network system.
In addition, a network of Macintosh computers can be administered with Apple Network Assistant, an all-in-one solution for remote assistance, system profiling and configuration, and software distribution. With this software, administrators can provide assistance to end users, get system profiles, reconfigure system settings, and distribute applications across hundreds of computers—all from a central location, over both TCP/IP and AppleTalk networks.
Figure 3
LAN surveyor is Neon Software’s Mac OS network mapping, monitoring, and reporting application.
Management
AppleTalk networks can be managed with the SNMP Administrator program provided by Apple Computer. This program lets administrators set up and monitor groups of computers on the network using the Simple Network Administration Protocol (SNMP). When SNMP is not enough, there are third-party network management products that run on the Macintosh. One of these products is Neon Software’s LAN surveyor.
LAN surveyor graphically draws the network, which displays network objects—computers, printers, routers, and other nodes—and their relationships (Figure 3), provides real-time troubleshooting capability, and uses SNMP to profile and monitor network devices. Network objects are queried in real time for details including SNMP data, responder information, zone information, and AppleTalk services. If the devices on the network change, the map can easily be updated to show any changes.
LAN surveyor tests the network for responsiveness, alerts managers to problems, and shows how problems relate to other parts of the map. Device profiling, reporting, and traffic monitoring features provide the data needed to configure the network for efficient performance and to determine resource requirements. Other capabilities of LANsurveyor include the collection of asset and resource management data, software inventory and license metering, electronic software distribution, remote administration, and task scheduling.
Last Word
The AppleTalk protocol makes it easy to set up small to midsize networks, and does not consume as much bandwidth as some other protocols, such as IPX (Internetwork Packet Exchange). However, the features that make Ap-pleTalk easy to use, such as computers announcing their presence to the rest of the network whenever they “wake up,” tend to bog down the performance of larger networks. Moving to IP eliminates the problems associated with AppleTalk’s network chatter File, print, and Web services, among others, are all seamlessly accessible via IP on the Macintosh. Mac-to-NT connectivity is now easy to achieve with third-party software, and Apple has added support for SNMP to the MacOS and is working with other vendors to improve Mac management tools in cross-platform environments. See Also Linux, NetWare, Windows NT, UNIX
