Telescript White Paper #2

TELESCRIPT TECHNOLOGY: SCENES FROM THE ELECTRONIC MARKETPLACE GENERAL MAGIC, INC.
TELESCRIPT WHITE PAPER #2 PAGE 1
Telescript Technology
Scenes from the Electronic Marketplace
Version 1.0
17 December 1993
James E. White
General Magic, Inc.
Contents
Contents ............................................................................................................... 1
Introduction ......................................................................................................... 1
Telescript Technology Overview ......................................................................... 2
The Electronic Marketplace ....................................................................................... 2
The Telescript Language ............................................................................................ 3
The Telescript Engine................................................................................................. 3
Monitoring Changing Conditions ....................................................................... 4
The User Experience................................................................................................... 4
How Agents Provide the Experience.......................................................................... 4
Variations on the Theme ............................................................................................ 6
Doing Time-Consuming Legwork ....................................................................... 6
Variations on the Theme ............................................................................................ 8
Using Services in Combination........................................................................... 8
Variations on the Theme .......................................................................................... 10
Telescript Products............................................................................................ 11
Introduction
Today’s networks—especially public networks—pose an insurmountable bar-
rier to the development of communicating applications, applications that
have a functional need to distribute themselves among both the computers of
individual users and the computers that users share, the servers. Such
distribution is not possible in practice for reasons of logistics, portability, and
safety.
General Magic has developed a software technology that overcomes this bar-
rier. That technology, Telescript technology, enables the creation of a new

breed of value-added network that supports the development of communicat-
ing applications by making the entire network an open platform for develop-
ers. While conceived for a new breed of consumer electronics product, the per-
sonal intelligent communicator, Telescript technology is equally at home in
more familiar settings, for example, that of the personal computer.
A companion paper, Telescript Technology: The Foundation for the Electronic
Marketplace, provides a technical overview of the Telescript technology and
presents the vision of an electronic marketplace based upon it. The present
paper explores a variety of communicating applications that could, but do not
yet, exist. These are scenes from the electronic marketplace of the future.
This paper has four sections. The first, intended especially for those who
haven’t read the companion paper, provides an abbreviated overview of Tele-
script technology. The other sections present varied scenarios that illustrate
the technology’s use in communicating applications. Each of these three sec-
tions has a theme, develops one variation of the theme, and sketches others.
Telescript technology will appear initially in products and services offered by
Apple, AT&T, Matsushita, Motorola, Philips, and Sony.
Telescript Technology Overview
The Electronic Marketplace
Telescript technology integrates an electronic world of computers and the net-
works interconnecting them. This world is filled with Telescript places occu-
pied by Telescript agents. Each place or agent represents, in the electronic
world, an individual or organization in the physical world, its authority. A
place’s or agent’s authority is revealed by its telename which can’t be falsi-
fied.
A place, but not an agent, has a teleaddress1 which designates the place’s lo-
cation in this electronic world and which reveals the authority of the individ-
ual or organization operating the computer in which the place is housed.
The typical place is permanently occupied by an agent of the place’s author-
ity, and is temporarily occupied—visited—by agents of other authorities. A
theater ticketing place, for example, might be occupied by a ticketing agent
able to provide information about theater events and to sell tickets to those
events. The ticketing place might be visited by agents of other authorities,
agents wishing to avail themselves of the service the ticketing agent offers.
A Telescript agent is a computer program—in modern terms, a software ob-
ject—with the unusual ability to transport itself from one place in this elec-
tronic world to another. The place to which an agent travels may be either in
the same computer as the place from which it travels or in a different com-
puter. In the latter case, the agent’s travel involves the use of a network.
An agent travels to obtain a service that is offered remotely. A user’s agent,
for example, might travel to the ticketing place, from a place in the user’s
personal communicator, to obtain theater tickets from the ticketing agent. In
general, one agent travels to first meet and then interact with another agent.
The agents interact programmatically using object-oriented techniques.
1 The companion paper
discusses telenames, but
not teleaddresses.

We describe the electronic world that Telescript technology enables as an
electronic marketplace because it provides a setting in which the agents of the
providers and consumers of goods and services can find and interact with one
another. Varied forms of electronic commerce are possible as a result.
The Telescript Language
The centerpiece of Telescript technology is a computer language for remote
programming developed by General Magic. The Telescript language supple-
ments, not replaces, systems programming languages such as C and C++.
Only the parts of an application that require the ability to move from one
place in a network to another—the agents—are written in the Telescript lan-
guage. Telescript technology makes such movement possible but also safe.
The Telescript language is communication-centric. Just as PostScript™ is de-
signed for describing complex images, and Mathematica™ for performing
complex mathematics, so the Telescript language is designed for carrying out
complex networking tasks: navigation, transportation, authentication, etc.
Agents travel using the Telescript language’s go instruction. The agent need
merely present a ticket that identifies its destination. An agent executes go
when it must get from one place to another. The next instruction in the
agent’s program is executed at the agent’s destination, not at its source. Thus
the Telescript language reduces networking to a single program instruction.
A ticket designates either a particular place by name, any place of a specified
authority, any place at a specified address, any place at an address of a speci-
fied authority, or any place of a specified class, that is, any place providing a
specified service.2 These constraints can be imposed in combination.
Another instruction available to the Telescript programmer is meet, which
enables one agent to meet another. The agent presents a petition which iden-
tifies the agent to be met. An agent executes meet whenever it wants assis-
tance. By meeting, the agents receive references to one another which enable
them to interact as peers using object-oriented programming techniques.
A petition designates either a particular agent by name, any agent of a speci-
fied authority, or any agent of a specified class, that is, any agent providing a
specified service.3 These constraints can be imposed in combination.
The Telescript Engine
A Telescript agent is powerless in the absence of a Telescript engine, which
implements the Telescript language by interpreting programs written in it.
General Magic has developed two implementations of the Telescript lan-
guage. One of these two engines is designed for personal intelligent communi-
cators, the other for public services and enterprise servers.
Any Telescript engine—at least conceptually—has three application program
interfaces (APIs) through which the engine draws upon the resources of the
computer platform on which it runs. The storage API provides access to the
platform’s non-volatile store which the engine uses to preserve agents in the
face of a crash. The transport API provides access to the platform’s communi-
cation media which the engine uses to send agents to other engines, and to
discusses only the first of
these forms of place des-
ignation.
discusses only the first of
these forms of agent des-
ignation.

receive agents from other engines. The external applications API, finally, al-
lows the bulk of an application written, for example, in C to create and inter-
act with the parts written in the Telescript language, that is, the agents.
Monitoring Changing Conditions
The User Experience
Two weeks from now, Chris must make a two-day business trip to Boston. He
makes his airline reservations using his personal communicator. He’s ready
to go. Chris’ schedule in Boston proves hectic. On the second day, he’s run-
ning late. Two hours before his return flight is scheduled to leave, Chris’ per-
sonal communicator informs him that the flight has been delayed an hour.
That extra hour enables Chris to avoid cutting short his last appointment.
The hour Chris saved was important to him. He could have called the airline
to see whether his flight was on time, but he was extremely busy. Chris was
startled—pleasantly so—when notice of his flight’s delay hit the screen of his
personal communicator. When he used his communicator to arrange his trip
two weeks ago, Chris had no idea that this was part of the service.
How Agents Provide the Experience
Chris can thank one Telescript agent for booking his round-trip flight to
Boston, another for monitoring his return flight and notifying him of its de-
lay. The first of these two tasks was accomplished in the following steps:
Electronic Shopping CenterTrip Planning
Application
Airline
PIC Mainframe
Airline
Chris
#1
1
2
3
4
5
Chris
#1
Network
6
78
Directory
Direc-
tory
1. Chris gives to the trip planning application he bought for his personal
communicator the dates of his trip, his means of payment (e.g., the num-
ber and expiration date on his Visa card), his choice of airline, etc. If he’s
used the application before, it has much of this information already.
2. The application creates a Telescript agent of Chris’ authority and gives
Chris’ flight information to it. The part of the application written in C
creates and interacts with the part written in the Telescript language,
the agent, using the Telescript engine in Chris’ personal communicator.4
3. The agent travels from Chris’ personal communicator to the electronic
marketplace’s airline place. It does this by executing the Telescript lan-
guage’s go instruction with a ticket that designates the airline place by
its authority and class.
4 The Telescript engine is
accessed via its external
applications API.

4. The agent meets with the airline agent it finds in the airline place. It
does this by executing the Telescript language’s meet instruction with a
petition that designates the airline agent by its authority and class.
5. The agent gives Chris’ flight information to the airline agent, which
compares the authority of Chris’ agent to the name on Chris’ Visa card
and then books his flight, returning a confirmation number and itiner-
ary. The agents interact using object-oriented programming techniques.
6. The agent returns to Chris’ personal communicator. It does this by exe-
cuting the go instruction with a ticket that designates home by its name
and address, information the agent noted before leaving home.
7. The agent gives the confirmation number and itinerary to the trip plan-
ning application.5 Its work complete, the agent terminates.
8. The application conveys the confirmation number and itinerary to Chris,
perhaps making an entry in his electronic calendar as well.
The remaining task, that of monitoring Chris’ return flight and informing
him if it’s found to be delayed, is carried out in the following additional steps:
Electronic Shopping CenterTrip Planning
Application
PIC Mainframe
Airline
Chris
#2
Network
Chris
#2
Directory Airline
9
1 0
1 1
1 2
1 21 2
Direc-
tory
9. Before leaving the airline place (in step 6), the agent that made Chris’
reservation creates a second agent,6,7 also of Chris’ authority, and gives
Chris’ confirmation number and itinerary to that agent.
10. Noting that the flight is two weeks hence, the newly created agent puts
itself to sleep until the day of Chris’ trip. The airline place may charge
the agent (and thus Chris) a fee for its room and board.
11. On the day of Chris’ flight, the agent arises. Throughout the day, the
agent checks Chris’ flight once an hour. On each occasion, the agent first
meets with the airline agent by executing the meet instruction with a
petition that designates the airline agent by its authority and class, and
then interacts with the airline agent using object-oriented programming
techniques. In one of these checks, it notes the delay in Chris’ flight.
12. The agent (as in step 6) returns to Chris’ personal communicator, the
agent (as in step 7) notifies the trip planning application of the delay in
Chris’ return flight and then terminates, and the application (as in step
8) gives Chris the information that allows him to complete his meeting.
5 The agent accesses the
application through the
Telescript engine’s exter-
nal applications API.
6 Permits are described
in the companion paper.
does not discuss the fact
that one agent can create
another if its permit al-
lows. The parent can
grant its children only
capabilities it has itself,
and must share its own
allowance with them.

Variations on the Theme
This first scenario demonstrates how Telescript agents can monitor changing
conditions in the electronic marketplace. There are many variations:
■ Chris learns by chance that the Grateful Dead are in town next month. He
tries to get tickets, but finds that the concert sold out in twelve hours.
Thereafter, Chris’ agent monitors Ticketron every morning at 9 am. The next
time a Grateful Dead concert in Chris’ area is listed, the agent snaps up two
tickets. If Chris can’t go himself, he’ll sell the tickets to a friend.
■ Chris buys a television from The Good Guys. Chris’ agent monitors the lo-
cal consumer electronics market for 30 days after Chris’ purchase. If it finds
the same set for sale at a lower price, the agent notifies Chris so that he can
exercise the low price guarantee of the store he patronized.
■ Chris invests in several publicly traded companies. Chris’ agent monitors
his portfolio, sends him biweekly reports, and notifies him of any sudden
change in stock price. The agent also monitors the wire services and relays to
Chris any news stories about the companies whose stock he owns.
■ Mortgage rates continue to fall. Chris refinances his house at a more favor-
able rate. Thereafter, Chris’ agent monitors the local mortgage market and
notifies him if rates drop 1% below his new rate. With banks forgoing closing
costs, such a drop is Chris’ signal to refinance again.
Doing Time-Consuming Legwork
The User Experience
John’s in the market for a camera. He’s read the equipment reviews in the
photography magazines and Consumer Reports and visited the local camera
store. He’s buying a Canon EOS A2. The only question that remains is: from
whom? John poses that question to his personal communicator. In fifteen
minutes, John has the names, addresses, and phone numbers of the three
shops in his area with the lowest prices. A camera store in San Jose, 15 miles
away, offers the A2 at $70 below the price his local camera shop is asking.
The $70 that John saved, needless to say, was significant to him. John could
have consulted the three telephone directories covering his vicinity, made a
list of the 25 camera retailers within, say, 20 miles of his office, and called
each to obtain its price for the EOS A2, but who has the time? John now con-
siders his personal communicator to be an indispensable shopping tool.
John can thank a Telescript agent for finding the camera store in San Jose, a
task that it accomplished in the following steps:

Electronic Shopping CenterShopping
Application
PIC Mainframe
John
John
CameraDirectory
Direc-
tory
John
Network (Other
camera
places
not shown)Cam-
era
1
2
3
4
5
6
7
8
9
1 01 1
1. John gives to the shopping application he bought for his personal com-
municator the make and model of the camera he’s selected. He also iden-
tifies the geographical area for which he wishes pricing information.
2. The application creates a Telescript agent of John’s authority and gives
John’s shopping instructions to it. The part of the application written in
C creates and interacts with the part written in the Telescript language,
the agent, using the Telescript engine in John’s personal communicator.8
3. The agent travels from John’s personal communicator to the electronic
marketplace’s “yellow pages” directory place. It does this by executing
the go instruction with a ticket that designates the directory place by its
authority and class.
4. The agent meets with the directory agent it finds in the directory place.
It does this by executing the meet instruction with a petition that desig-
nates the directory agent by its authority and class.
5. The agent obtains from the directory agent the directory listing for every
camera retailer about which the directory has information. The two
agents interact using object-oriented programming techniques. The
agent then narrows the list of retailers to those shops in the geographi-
cal area it was asked to explore.
6. The agent visits, in turn, the electronic storefronts of those retailers.
Each storefront is another place in the electronic marketplace. For each
trip the agent uses the go instruction with a ticket that designates the
agent’s destination by its name and address, information the agent ob-
tained from the storefront’s directory listing.
7. The agent meets with the camera agent it finds in each camera place it
visits. It does this by executing the meet instruction with a petition that
designates the camera agent by its authority and class.
8. The agent gives to the camera agent the camera’s make and model and
receives a price in return. The agents interact using object-oriented pro-
gramming techniques. The agent retains information about this particu-
lar shop only if the shop proves a candidate for the agent’s top-three list.
9. Once it has visited all the shops on its list, the agent returns to John’s
personal communicator. It does this by executing the go instruction with
8 The Telescript engine is
accessed through its ex-
ternal applications API.

a ticket that designates home by its name and address, information the
agent noted before starting its journey.
10. The agent makes its report to the shopping application.9 Its work com-
plete, the agent terminates.
11. The application in turn presents the report to John, perhaps making an
entry in John’s electronic diary as a permanent record.
This second scenario demonstrates how Telescript agents can find and ana-
lyze information in the electronic marketplace. There are many variations:
■ Chris hasn’t talked to his college friend, Doug, in twenty years. He remem-
bers that Doug was a computer science major. Chris’ agent searches the trade
journals and conference proceedings—even very specialized ones—in the hope
that Doug has written or spoken publicly. The agent discovers that Doug has
published several papers, one as recently as two years ago. The agent returns
with Doug’s address in LA where he has lived, as it turns out, for five years.
■ It’s Friday and Chris has been in Chicago on business all week. Expecting
to go home today, Chris is asked to attend a Monday morning meeting in
New York instead. He faces an unplanned weekend in midtown Manhattan.
Chris’ agent discovers that Charles Aznavour—Chris has every recording
Aznavour ever made—is performing at Radio City Music Hall on Saturday
night. With Chris’ approval, Chris’ agent purchases him a seat for the con-
cert.
■ Chris is in the market for a used car. He’s had great experience with
Toyota’s. Chris’ agent examines the classified sections of all fifteen Bay Area
newspapers, and produces for Chris a tabular report that includes all used
Toyota’s presently on the market. The report lists the cars by model, year,
and mileage, allowing Chris to easily make comparisons between them.
■ Chris yearns for a week in Hawaii. Chris’ agent voices his yearning in the
electronic marketplace, giving details that Chris has provided: a few days on
Kauai, a few more on Maui, beach-front accommodations, piece and quiet.
The agent returns with a dozen packages—from American Airlines, Hilton
Hotels, Aloha Condominiums, Ambassador Tours, etc.. Unlike the junk mail
Chris routinely receives by post, many of these offers are designed specifically
for him. Their providers, in effect, are competing for his business.
Using Services in Combination
The User Experience
Mary and Paul have been seeing each other for years. Both lead busy lives.
They don’t have enough time together. But Mary’s seen to it that they’re
more likely than not to spend Friday evenings together. She’s arranged—
using her personal communicator—that a romantic comedy is selected and
ready for viewing on her television each Friday at 7 pm, that pizza for two is
delivered to her door at the same time, and that she and Paul are reminded,
9 The agent accesses the
application through the
Telescript engine’s exter-
nal applications API.

earlier in the day, of their evening together and of the movie to be screened
for them.
Paul and Mary recognize the need to live well-rounded lives, but their de-
manding jobs make it difficult. Their personal communicators help them
achieve their personal, as well as their professional objectives. And it’s fun.
Mary relies upon a Telescript agent to orchestrate her Friday evenings. Born
months ago and waiting patiently in a quiet corner of the electronic market-
place for most of each week, the agent takes these steps each Friday at noon:
Electronic Shopping Center
Mainframe
Mary
#1
VideoResting
Mary
#1
Network
Video
Mary
#1
Pizza
Pizza
1
2
3
4
5
6
7
8
1. Mary’s agent maintains a record of the films it selected on past Fridays
to avoid selecting one of those films a second time.
2. The agent travels, within the electronic marketplace, from its place of
resting to the video place. It does this by executing the go instruction
with a ticket that designates the video place by its authority and class.
3. The agent meets with the video agent it finds in the video place. It does
this by executing the meet instruction with a petition that designates
the video agent by its authority and class.
4. The agent obtains from the video agent the catalog listing for each ro-
mantic comedy in its inventory. The agent selects a film at random from
among the more recent comedies, but avoiding the films it has selected
before (information it carries with it). The agent orders the film from the
video agent, charging it to Mary’s Visa card and instructing the video
agent to transmit the film to her home at 7 pm. The video agent com-
pares the authority of Mary’s agent to the name on the Visa card. The
two agents interact using object-oriented programming techniques.
5. The agent goes next to Domino’s pizza place. It does this by executing
the go instruction with a ticket that designates the pizza place by its
class and its authority.
6. The agent meets with the pizza agent it finds in the pizza place. It does
this by executing the meet instruction with a petition that designates
the pizza agent by its authority and class.
7. The agent orders one medium-size Pepperoni pizza for home delivery at
6:45 pm. The agent charges the pizza, as it did the video, to Mary’s Visa

card. The pizza agent, like the video agent before it, compares the au-
thority of Mary’s agent to the name on the Visa card the agent presents.
The two agents interact using object-oriented programming techniques.
8. Mary’s agent returns to its designated resting place in the network. It
does this by executing the go instruction with a ticket that designates
that place by its name and address, information the agent noted before
leaving the resting place earlier in the day.
What remains is for the agent to notify Mary and Paul of their evening ap-
pointment. This is accomplished in the following additional steps:
9. The agent creates two new agents of Mary’s authority and gives to each
the catalog listing of the selected film and the names of Mary and Paul,
respectively. Its work complete, the agent awaits another Friday.
10. One of the newly created agents goes to Mary’s mailbox place, while the
other goes to Paul’s. They do this by executing the go instruction with
tickets that designate the mailbox places by their class and authorities.
11. The agents meet with the mailbox agents they find in the mailbox
places. They do this by executing the meet instruction with a petition
that designates the mailbox agents by their class and authorities.
12. The agents deliver to the mailbox agents electronic messages that in-
clude the film’s catalog listing and that remind Mary and Paul of their
appointment with one another. The agents interact using object-oriented
programming techniques. The visiting agents terminate. The mailbox
agents subsequently convey the reminders to Mary and Paul themselves.
This third scenario demonstrates how Telescript agents can combine existing
services to create new, more specialized services. There are many variations:
■ Mary plans to take Paul to see Phantom of the Opera next weekend. Her
agent tries to book orchestra seats for Saturday or Sunday evening, succeeds
in getting them for Sunday, reserves a table at a highly regarded Indian
restaurant within walking distance of the theater, and (in a reversal of roles)
orders a dozen roses for delivery to Paul’s apartment that Sunday morning.
■ Mary’s travel plans change unexpectedly. Rather than return home this
evening as planned, she’s off to Denver. Mary’s agent alters her airline reser-
Electronic Post Office
MailboxMailbox
Electronic Shopping Center
Mainframe
VideoResting
Mary
#2
Network
Video
Pizza
Pizza
Mary
#3
9
1 0
1 0
Mary
Mary
#2
Paul
Mary
#3
1 1
1 11 2
1 2
Mainframe

vation, books her a non-smoking room at a Marriott Courtyard within fifteen
minutes of her meeting location, reserves her a compact car and provides her
with driving instructions, both to the hotel and to the meeting. The agent also
supplies Mary with a list of Indian restaurants in the vicinity.
■ Mary has begun to receive and to pay her bills electronically. Mary’s agent
receives each bill as it arrives, verifies that Mary has authorized its payment,
checks that the bill is in the expected range, and issues instructions to the
bank if it is. Mary’s agent prepares for her a consolidated monthly report and,
at tax time, sends a report of her tax deductible expenses to her accountant.
■ Mary subscribes to a daily newspaper, but it isn’t her idea of news. Mary’s
agent prepares and delivers to her each morning a personalized newspaper.
It include synopses of the major national and international news stories, but
goes on to provide the local news from her hometown in Virginia, the major
events of yesterday in her field, physics, the market activity of the stocks in
her portfolio, and Doonesbury, which she always finds gives her a chuckle.
Telescript Products
The Telescript technology is embodied in two products offered by General
Magic. Both involve the Telescript engine for services and servers.
The Telescript Developer’s Kit (TDK), available for several different
platforms, comprises object code for the Telescript engine and for platform-
specific implementations of its APIs. This product includes the tools, sample
programs, and documentation required to use Telescript technology to create
communicating applications. The product is aimed at developers of such
applications.
The Telescript Porting Kit (TPK) comprises source code for the Telescript en-
gine, along with the ancillary software and documentation needed to port the
engine to a new platform. This product is aimed at platform manufacturers.
Additionally, General Magic has developed a communicating application that
does personal, intelligent, multi-media messaging. Parts of the application
run on personal intelligent communicators, the sources and destinations of
messages. Other parts run on servers, which house the mailboxes through
which messages are routed. This work, along with the Telescript software
that underlies it, is the basis for a consumer messaging service which AT&T
will offer to the public beginning in 1994. Arising from this work are addi-
tional, electronic mail-specific products available from General Magic.

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