brad@cayman.com (Brad Parker) (12/19/89)
CAYMAN SYSTEMS BACKGROUNDER
In large networks, managers need to connect multiple platforms
using the most efficient network architecture. They must respond to
users who demand data and file sharing, easy communication via
electronic mail, and efficient use of resources like printers and
storage devices. And managers must plan for future expansion. To
address these needs, networking products from Cayman Systems are
designed to support standard protocols, open systems, and
heterogeneous platforms.
The GatorBox: AppleTalk to Ethernet gateway
Introduced in August 1988, the GatorBox is an intelligent
AppleTalk-to-Ethernet gateway that provides Macintosh users with
access to network services commonly found on Ethernet networks. The
GatorBox integrates Macintosh users into Ethernet environments by
offering them a full range of network services, including file
sharing, file transfer, mail, printing and terminal emulation.
GatorBox features include:
- AppleTalk routing -
With the GatorBox, EtherTalk-based Macintoshes can access
LocalTalk-based resources, like AppleShare servers and LaserWriters.
- File sharing -
Macintosh users can access AppleShare file servers on Ethernet
(likeVMS-based VAXs running AppleShare software from Pacer or Alisa
and UNIX systems with Columbia AppleTalk Protocols [CAP]).
- Terminal emulation -
Macintoshes users can log in as VT100 terminals to any
TCP/IP-based computers using NCSA Telnet, terminal emulation software
thatUs shipped with the GatorBox.
- Configuration -
The GatorBox's GatorKeeper software allows the network
administrator to set access privileges and configure other network
options from a Macintosh on LocalTalk or Ethernet.
- GatorShare -
With GatorShare software running on the GatorBox, the GatorBox
translates AppleShare into NFS (Network File System from Sun
Microsystems), allowing Macintoshes to share files with Suns, VAXs,
NeXTs, Silicon Graphics, Apollos, or any other workstations or
minicomputers that support NFS.
Why is the GatorBox called an "intelligent gateway?" The
GatorBox provides application-level connectivity to services on
Ethernet and LocalTalk. Other gateways provide only transport-level
connectivity for routing data on Ethernet and LocalTalk. To use a
gateway that provides only transport-level connectivity, the user must
typically install software on both the Macintosh client and the
Ethernet-based host, as well as download software into the gateway.
The software that lets these gateways implement network services is
available from third-party Macintosh software developers or from the
public domain.
Page Two
Backgrounder
GatorShare: Macintosh to UNIX file sharing
The GatorBox runs sophisticated networking software that
provides application level connectivity between Macintoshes on
LocalTalk or EtherTalk, and UNIX workstations on Ethernet.
GatorShare, the first of the GatorBox applications, provides file
sharing between Macintoshes and computers with NFS on Ethernet.
Supports Standard Protocols:
The use of standard protocols protects the network manager's
investment against obsolesence. The Cayman software products translate
between the AppleTalk protocols used by Macintosh computers on
LocalTalk or EtherTalk and the TCP/IP protocols used on most Ethernet
networks.
GatorShare translates the entire AppleTalk protocol suite --
starting with LLAP at the LocalTalk cable and moving up through all
six levels to AFP (the AppleTalk file-sharing protocol) -- into the
most popular suite of protocols on Ethernet: the file-sharing protocol
NFS from Sun Microsystems and the TCP/IP protocols developed by the
Department of Defense.
GatorShare translates the entire AppleTalk and NFS protocol stacks, so both
Macintoshes and NFS computers use their own native protocols.
Page Three
Backgrounder
Since GatorShare transparently handles protocol translation,
network managers don't need to install special network operating
software on any of the computers in the network. Computers use their
native protocols and need no additional networking software. The
AppleShare client software, which is part of the Macintosh system
software, is distributed with GatorShare.
Supports Heterogeneous Platforms:
Increasingly, network managers are expected to smoothly
integrate many different computers into a single network. By
translating AppleShare into NFS, GatorShare lets Macintoshes share
files with Suns, NeXTs, VAXs, Apollos, Sequents, Macintoshes with
A/UX, or any other computer that supports NFS.
In a heterogeneous network, users want to use familiar
commands, instead of learning multiple interfaces. With GatorShare,
access is transparent to the Macintosh user: files on the server
appear as AppleShare volumes. The user can transfer files and
applications to the local disk by dragging their icons, or open them
on a remote disk by double-clicking..
Multiple Client, Multiple Server Networks:
GatorShare lets Macintoshes running the AppleShare client
software access computers that support NFS as if they were AppleShare
servers. This gives the individual user access to expanded file
storage. For the network manager, the client-server architecture
ensures data integrity and data security.
All of the NFS workstations can act as file servers for all of the Macintoshes.
Page Four
Backgrounder
GatorMail: Macintosh to UNIX electronic mail
GatorMail is the first software gateway between Macintosh and
UNIX mail systems. It links QuickMail or Microsoft Mail networks with
electronic mail networks supported by SMTP, the most common mail
protocol for UNIX workstations on TCP/IP networks.
In a homogeneous environment consisting of UNIX workstations,
exchanging electronic mail reliably and consistently is a known art.
Increasingly, however, Macintosh computers have proliferated in
environments where UNIX workstations are common. Until now they have
been cut off from the world of UNIX mail. UNIX users have become
accustomed to sending electronic mail to and from UNIX machines. Now
they want to send mail to and from Machintoshes in the same way.
Solutions to this problem have emerged that give the user
varying levels of connectivity. The simplest solution is terminal
emulation. The Macintosh is connected to the UNIX computer via
asynchronous serial line, usually running at 9600 baud. The user runs
a terminal emulator program that logs into the UNIX workstation
directly, creating a "window" into that environment. The user
can read as well as send UNIX mail.
Terminal emulation.
Using terminal emulation, it's difficult to enclose Macintosh
files with the UNIX mail messages, or to save UNIX mail messages on
the Macintosh. Also, the terminal session is not cleanly integrated
into the Macintosh environment, so the user must learn the UNIX
commands to send mail.
Page Five
Backgrounder
Another solution is to put TCP/IP protocols on the Macintosh
computer, letting it communicate with UNIX computers on TCP/IP
networks. With the release of Apple Computer's MacTCP, a TCP/IP
implementation for Macintosh computers, several non-commercial UNIX
mail solutions employing POP (Post Office Protocol) have been
developed at universities and released into the public domain.
Notable among these are mh-POP from Stanford University and a
HyperCard POP stack from the University of Minnesota.
POP mail network.
Essentially, POP mail gives the user access to UNIX mail
through a Macintosh front end, without the benefit of commercial
support. To implement this kind of mail, POP support must be added to
the protocols on the UNIX mail server. This requires some programming
and a great deal of support from the UNIX mail system administrator,
since POP services are not built into commercial UNIX systems. POP
mail also demands an understanding of TCP/IP on the part of the user.
Macintosh and SMTP Mail Systems.
Several commercial mail systems for the Macintosh have been
released or annouced that include gateway functions. These offer the
user full integration with different mail networks, while still using
the familiar Macintosh user interface. Microsoft Mail 2.0, CE
Software's QuickMail and TOP's InBox all provide integrated support
for mail gateways. Cayman SystemsU GatorMail-M and GatorMail-Q
take advantage of these gateway capabilities to connect users
transparently with UNIX mail networks via the TCP/IP and SMTP
protocols.
Page Six
Backgrounder
GatorMail forwards Macintosh mail messages to and from UNIX mail networks.
In the Macintosh environment, proprietary servers using
proprietary mail protocols like QuickMail or Microsoft Mail are the
norm. There is no Macintosh standard for sending electronic mail. In
the UNIX environment, mail protocols are standardized. UNIX computers
on a TCP/IP network send mail back and forth between each other using
Simple Mail Transfer Protocol (SMTP). Because there are standards
governing the use of SMTP and the TCP/IP protocols, it's
straightforward for a group of UNIX computers to send mail back and
forth on a network.
Connecting heterogenous networks via standard protocols:
GatorMail takes advantage of the standard SMTP protocol to
link UNIX computers and Macintoshes in a single electronic mail
network. SMTP is a DOD (Department of Defense) mail protocol standard
that is supported by most UNIX networks and by other computers that
support TCP/IP protocols. For instance, Macintosh users can send mail
to users of workstations from Digital Equipment, Sun, Apollo,
Intergraph, NeXT and others.
There are two versions of GatorMail. GatorMail-M links
Microsoft Mail 2.0 users with SMTP mail users. GatorMail-Q links
QuickMail users with SMTP mail users. Both programs feature a
transparent interface that lets users send mail using their own mail
software. Neither UNIX users nor Macintosh users need to learn new
commands to send mail to each other.
Like GatorShare, GatorMail is easy to configure. It runs on
the Macintosh mail server, and no additional software needs to be
installed on the Macintoshes or workstations in the network.
Page Seven
Backgrounder
GatorPrint: Macintosh to UNIX printing
A third network application, called GatorPrint, will be
available in 1990. GatorPrint will initially enable UNIX-based
workstations and minicomputers that support the "lpr" printing
protocol to print to LocalTalk-based Laserwriters. Future
enhancements to GatorPrint will allow Macintosh users to print to
PostScript-based printers connected to UNIX-based computers on
Ethernet.
Currently, GatorBox users can print from UNIX workstations to
Laserwriters using CAP (Columbia AppleTalk Protocols). CAP is a
widely used printing protocol for computers that support the TCP/IP
protocol stack. It was developed at and is available from Columbia
University.
Cayman, the Cayman logo, GatorShare, GatorMail, GatorPrint, GatorCard
and GatorBox are trademarks of Cayman Systems, Inc. Microsoft and the
Microsoft logo are registered trademarks of Microsoft Corporation.
UNIX is a registered trademark of AT & T Information Systems.
Ethernet is a registered trademark of Xerox Corporation. Network File
System (NFS) is a trademark of Sun Microsystems, Inc.