WO1996021189A1

WO1996021189A1 - Network support of supplemental local applications

Info

Publication number: WO1996021189A1
Application number: PCT/US1995/017108
Authority: WO
Inventors: Randy W. Raynak; Viktor Kushnir
Original assignee: Compuserve Incorporated
Priority date: 1994-12-30
Filing date: 1995-12-29
Publication date: 1996-07-11
Also published as: AU4692996A; US5680549A

Abstract

A system for network support of supplemental local applications allows one workstation (10) application, communicating with a host computer (30) on a network, to invoke a second workstation application that takes control of the first application's connection to the network. The first application waits for the second application to terminate and then resumes control of the network connection so that the user is returned to the same point in the work session. The transistions between the workstation applications are automatic and facilitated by the network through a protocol known by both workstation applications and the network. Although the user is aware of the change in applications, the user may never know that an on-line service host facilitated the transition between the applications.

Description

NETWORK SUPPORT OF SUPPLEMENTAL LOCAL APPLICATIONS

BACKGROUND AND SUMMARY OF THE INVENTION

The present invention relates generally to a computer system that manages transitions

between two workstation software apphcations, running in a graphical interface environment

on a multitasking operating system, so that they may use the same network connection to

access information residing on a host computer connected to the network. More particularly,

the present invention relates to a system for enabling a first workstation application,

communicating with a host computer on a wide area network, to invoke a second workstation

application and allow the second workstation application to take control of the first

workstation's connection to the wide area network and then resume control of the network

connection when the second workstation application terminates.

Today, online information services, such as CompuServe® Incorporated, offer their

subscribers access to information and services provided by a multitude of host computers

connected via a wide area network. Subscribers usually connect to the network through a

mode Once connected, subscribers access the information and services through software residing on the subscribers' workstations. Among the functions performed by the workstation

software are managing the connection to the wide area network and managing the

presentation of information to the subscriber. The access software that the subscriber uses to

communicate with the online information service may be provided by the service itself or it

may be provided by another vendor. In either case, the software is general purpose for the

online service and provides the base functionality needed to interact with the online service.

Online information services today provide a wealth of information and services to their

subscribers. In addition, they provide sophisticated software to help their subscribers access the information they need or want. Despite the variety of needs and interests that online

information services are able to meet, subscribers often have a desire to access information and

services that are not part of the product suite of the online information service provider (i.e.,

outside or special apphcations). For example, a subscriber may be interested in accessing

5 travel information in order to plan a trip. Although some travel information may be available

from the online service, the travel planner may be able to get more information from an

outside vendor that specializes in compiling and organizing up-to-date travel information f om

a variety of sources such as hotels, restaurants, and airlines. In addition, the information may

be easier to access and understand if the travel planner uses special purpose, rather than online

o service general purpose, access software for presentation and display.

Today, subscribers usually are required to leave the online service and connect to a host that is not part of the online service (i.e., an outside host) in order to access the outside

application. In most cases, subscribers use special access software to connect to and to

communicate with the outside host. This method of accessing the outside application may be

5 inconvenient and inefficient. First, the subscriber may be required to leave the online service. Next, the subscriber may be required to invoke the special access software used to connect to

and communicate with the outside host. Depending on the sophistication of the access

software, the subscriber may need to know special commands to access and use the outside

host. Finally, depending on the access mechanism, the subscriber may be required to make a

o long distance telephone call to connect to the outside host.

Although these outside applications could be integrated into the product suite of the

online information service provider, doing so may not be desirable. For example, the online

service's general purpose access software that is used to interact with the online service may

not have the functionality required to interact with a specialized, outside application. The

5 general purpose access software provided by the online service may have to be modified to accommodate the outside apphcation thereby making the software more cumbersome and

difficult to use. In addition, the online service provider, rather than the outside vendor, may

need to assume some responsibility for maintaining the outside apphcation.

The present invention- Supplemental Local Apphcation Protocol (hereinafter SLAP)-addresses the needs of both the subscribers and the online information service

providers. The present invention provides a mechanism to allow special apphcations, also

referred to as supplemental local apphcations, to be supported by the online service. These

special apphcations include software residing on an outside host computer as well as

workstation software for managing a connection to the outside host and managing the

presentation and display of information. First, the invention allows vendors of special

apphcations to make their products more accessible by making them available through the

wide area network of the online service provider. Access through the online service wide area

network may mean that more subscribers can connect through local, rather than long distance,

telephone calls. In addition, the invention allows subscribers, who have connected to the

online service using the online service's general purpose access software, to then use a

supplemental local apphcation to interact with the special apphcation residing on a host

computer that is not a part of the online service. Once the subscriber has finished interacting with the special apphcation, the invention returns the subscriber to the general purpose

software session with an online service host computer. The present mvention manages the

transitions between the online service software and the supplemental local apphcation so that

the subscriber is not required to interrupt one session in order to start another. In addition, the

invention facilitates transitions between the outside and online service host computers so that

the subscriber is not aware the transition is taking place.

The needs of subscribers are met because they may access outside apphcations without

actually leaving the online information service. In addition, subscribers may take full advantage of the outside apphcation because they can use special purpose, rather than general purpose, software to interact with the apphcation. Finally, the online information service provider's involvement with the outside apphcation may be minimized The online service

makes the outside apphcation accessible to a wide subscriber base, but it is not required to

assume the added responsibihties of maintaining the special purpose access software for the

workstation or the special apphcation residing on the foreign host. Furthermore, the online

service provider is not required to modify its general purpose access sofhvare to accommodate

a variety of special apphcations. The advantages of the present invention are explained further

by the accompanying drawings and detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic representation of one embodiment of the present invention for

using a workstation to run general purpose and special purpose apphcations to access online service and foreign host computers, shown in two steps in Figures 1A and IB.

Figure 2 is a state diagram that represents possible states and transitions for one embodiment of the present invention.

Figure 3 is a flow diagram of the preferred system of workstation transitions for the

present invention.

Figure 4 shows a preferred method for designing or modifying a supplemental local

apphcation to communicate with the online service network.

Figures 5A and 5B show a connection diagram illustrating the steps of transferring a

network connection between a primary workstation apphcation and a supplemental local

apphcation. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring now to Figure 1A, one embodiment of the present invention is shown.

Figure 1A is a schematic representation of one known method for allowing a user at a

workstation 10 to connect to a host computer 40 through a network node 30. The

5 workstation 10 may be connected to the network node 30 via a modem 20. The modem

connection may be through a cable modem or a modem pool server. Other options may be available as well. The online service host computer 40 and a foreign host computer 50 are

connected via a wide area network. The online service network node 30 manages the

workstation's connections to the host computers. One network node is shown for simplicity

i o although actually more than one network node may be involved in the connection.

A distinction is made between online service network nodes/hosts and foreign hosts to

indicate who owns, operates, and maintains the equipment. The online service owns, operates,

and maintains the network node and online service host computer. Control over these devices,

as well as others that are part of the wide area network, allows the online service to define

15 how they will communicate. The devices that belong to the online service may use a common language or protocol that facilitates, and possibly optimizes, communication and data

transfers. As a result, new devices that understand the protocol may be integrated easily into

the online service wide area network. A host is considered foreign if it is not owned,

operated, or maintained by the online service. 0 Referring to Figure 1A, the connection to the host computer 40 is established,

preferably, through the general purpose access software running on the workstation 10.

Preferably, this software is provided by the online service so that it knows the online service

protocol and may take advantage of special features within the protocol that facilitate data

transfers and other communications. This online service general purpose access software may

5 be referred to as the Information Manager or IM. Preferably, the IM manages the connection to the online information service and manages the presentation of information to the user. The IM operates preferably in a multitasking, graphical interface environment such as the

Microsoft® Windows™ operating syste

Referring now to Figure IB, the workstation 10 may be equipped with another

apphcation for accessing information residing on a foreign host computer 50. It may serve a

specific purpose, and therefore, may be referred to as a special or supplemental local

apphcation. The supplemental local apphcation operates preferably in a multitasking,

graphical interface environment such as the Microsoft® Windows™ operating system. If the

supplemental local apphcation is provided by a third party, rather then the online service, it

may not understand details of the online service protocol and therefore, may not take

advantage of special protocol features that facilitate data transfers and other communications. Despite this possible limitation, the user may want to use the supplemental local apphcation

because it has special features, not present in the IM, for locating and displaying information.

In addition, the information that the user needs may be located on a foreign 50, rather than the

online service 40, host computer. Therefore, to take advantage of the supplemental local

apphcation, the supplemental local apphcation will be running and the workstation, in this

instance, is connected to the foreign host. The workstation 10, which is running the

supplemental local apphcation, may connect to the foreign host 50 via the online service network node 30.

The present invention manages a transition between the IM and online service host to

the supplemental local apphcation and foreign host. Figure 2, a state diagram, illustrates the

transition. The states and transitions described here are merely exemplary and illustrate a

preferred embodiment of the present invention. In the initial state (State 1), the user may not

be connected to the online service. When the user invokes the IM ( la), a connection is established between the user's workstation, the onhne service network node, and an online

service host (State 2).

At some point, the user may request access to the supplemental local apphcation and

the foreign host. This request is represented as transition 2a in the state diagram. In the third

state (State 3), the online service host and IM confirm the request and coordinate the

invocation of the supplemental local apphcation and connection to the foreign host. In the

next transition (3 a), the IM transfers control to the supplemental local apphcation and then

minimizes. The network node disconnects from the online service host and connects to the

foreign host. In the fourth state (State 4), the workstation is connected to the foreign host computer

via the network node. The workstation is running the supplemental local apphcation rather

than the IM. The supplemental local apphcation has control of the IMs connection to the

network node and the IM is in an inactive state. The user may use the supplemental local

apphcation to interact with the special apphcation residing on the foreign host computer.

Although the user is aware of the change between the IM and the supplemental local

apphcation, the user may never know that the online service host arranged the transition

between the programs running on the workstation and the transition between the host

computers.

The transition to the fifth state (4a) occurs when the user requests a return to the IM.

The network node arranges to disconnect from the foreign host computer and connect to an

onhne service host computer. An onhne service host then reactivates the IM which resumes

control of the network connection. Once again, the user is aware of the transition between the

supplemental local apphcation and the IM, but the user may never know that the online service

host arranged the transition between the programs running on the workstation and the

transition between the host computers. From State 4, the user may also request to disconnect from the online service (4b). When this request is made, the user returns to the initial state. As evident from the state

diagram, the user may decide to access a number of supplemental local apphcations before

ending the session. The present invention serves the user's requests and may facilitate any

number of transitions.

A protocol, called the Supplemental Local Apphcation Protocol or SLAP, is used to

manage the transitions between the apphcations running on the workstation and the transitions

between the online service and foreign host computers. SLAP is understood by the IM and

programs running on the online service host computers. The supplemental local apphcation

participates by accepting defined parameters passed on a command line and announcing itself

to the online service. SLAP permits apphcations that do not understand the details of the

online service protocol to nonetheless communicate and operate in the online service

environment. The supplemental local apphcation, which understands the Supplemental Local

Apphcation Protocol, is called a SLAP apphcation.

For the workstation, SLAP provides a means for invoking a SLAP apphcation and a

means for returning to the IM. Figure 3 presents a conceptual view of a preferred

embodiment of the present invention as h operates on the workstation. The present invention

operates when the user, who is connected to an online information service host via the IM, initiates a request to perform a task to be handled by the SLAP apphcation and a foreign host.

In Step 1, the IM invokes the SLAP apphcation. If the invocation is unsuccessful (Step 2),

the IM tries again up to five times (Step 3 and Step 4).

If the invocation is successful (through Step 2 or Step 4), Step 6 is executed and the

IM is minimized. The process of minimizing a workstation apphcation in a multitasking,

graphical interface environment is well known and is not explained here. When the IM

minimizes, it enters an inactive state, but it continues to run. As a result, information about the appearance of the workstation display and associated activities is preserved. Therefore,

the user may be returned to the point he or she was before the SLAP request was initiated.

In addition to minimizing, the IM passes to the SLAP apphcation a unique identifier or handle for the communication port through which the IM is connected to the network node

(Step 6). Using this information, the SLAP apphcation may then take control of the BV1

connection to the network node. The details of passing this information to the SLAP apphcation are explained in conjunction with Figure 4.

As shown in Step 7, after the IM minimizes, the SLAP apphcation starts running. The

SLAP apphcation takes control of the IM's, and hence the workstation's, connection to the

network node. Because the network node has estabhshed a connection to the foreign host, the

user may communicate with the foreign host via the SLAP apphcation. If the user tries to

maximize or switch to the HVI while the SLAP apphcation is running, the IM refuses to

respond to the request.

Although the IM is minimized and is technically inactive at this point, it has the abihty to momtor the state (active or not running) of the SLAP apphcation. The abihty of the DVI to

momtor the state of another apphcation running on the workstation is unique to SLAP as

implemented in a multitasking, graphical interface environment. It is well known that one

function of a multitasking operating system is to control the execution of apphcations.

Because the operating system performs this function, one apphcation running on the

workstation does not need to know whether other apphcations are running. However, one

objective of SLAP is to return the user to the IM session after the SLAP apphcation

terminates. This objective is accomplished through the IM's monitoring of the SLAP

apphcation. When the SLAP apphcation terminates (Step 8), the IM maximizes and takes

control of the connection (Step 9). As a result, the user returns to the same point he or she

was before the IM minimized. Referring now to Figure 4, setup details for the protocol are shown. Figure 4 illustrates one embodiment in which the present invention may operate. Details of the

protocol may vary without departing from the spirit and scope of the invention. To take

advantage of the protocol, the SLAP apphcation source code may be modified so that it can

announce itself to the online service and accept command line parameters (Step 1). The

announcement provides verification that the transition between the IM and the SLAP

apphcation succeeded. The announcement is preferably an ASCII string composed of the

characters ' ' (decimal 32) through '-' (decimal 126), inclusive. The process of creating an

ASCII string is known in the art and therefore, is not explained. Preferably, the announcement

format is as follows:

#<apphcation name>;<error check><CR> where <apphcation name> matches the apphcation name used by the online service host in a

request to invoke a SLAP apphcation and <error check> is the ASCII representation of the

sum of the ASCII values of the announcement bytes from '#' to ';', inclusive. The <error check> may be conφuted as a signed, sixteen bit integer value. The process of converting

integers to character strings is well known in the art and is not explained here. The

announcement may be terminated by a carriage return <CR>.

In Step 2, the SLAP apphcation is installed on the workstation. As shown in Step 2,

the name of the SLAP apphcation, along with an execution command, is added to the IM

initialization file. This information tells the IM about the SLAP apphcation so that at the

appropriate time, the IM may invoke the apphcation and pass to the SLAP apphcation the

information needed to take control of the network connection. The format is, preferably, as

follows:

application name> = <executable file><command line parameters>

where <application name> is an identifier sent to the IM by the network node when the user requests the SLAP apphcation. The <executable file> is a path name to the SLAP apphcation.

The <command line parameters> consist of static text and substituted parameters that the IM

may replace with current settings. The process of setting and reading a command line is well

known in the art and is not explained here. However, the information passed on the command

line is explained because it is through the command line, with the current settings, that the IM

is able to tell the SLAP apphcation how to take control of the connection to the network. The

available substitutable settings are:

%dir the current IM working directory

%userid the id used to log on in the current connection %port the current open communications port

%baud the current baud rate

%device the type of communications device in use

The type of the communications device (%device) tells the SLAP apphcation how to

interpret the communications port (%port) setting. The types of devices may include

"LOCAL," "NASI," and "NCSI." Preferably, the port parameter is set to the numeric value

for the identifier or open handle for the device.

After setup, the SLAP apphcation, the EM, and the online service host apphcation may

communicate using the protocol of the present invention. Figures 5 A and 5B show the steps

in the protocol. The form described here is merely a preferred or exenφlary embodiment. For

each step, the direction and a summary of the communication is shown. In addition, details of

the action are provided. Information in italics refers to messaging details that the IM, SLAP

apphcation, and online service host expect to send or receive.

Referring now to Figure 5 A, as shown in Step 1, the session may begin with an BVI

connection to an online service host. Both the IM and the online service host understand the

online service protocol so each may take advantage of special features in the protocol. In Step

2, the user initiates a request to be handled by the SLAP apphcation. In Step 3, the online

service host responds to the request by initiating an apphcation confirmation request from the IM to confirm that the SLAP apphcation has been installed on the user's workstation. If the

IM determines the SLAP apphcation exists, it responds to the online service host with an

apphcation confirmation response (Step 4). In Step 5, the online service host asks the IM to

invoke to SLAP apphcation. The request includes the apphcation name that the SLAP

5 apphcation is expected to use in its announcement. To respond to the request, the IM looks in

the IM intialization file for the requested SLAP apphcation and then makes a system call to

determine that the apphcation exists (Step 6). If the apphcation exists, the IM invokes the

SLAP apphcation and passes the current communication settings via the command line so that

the apphcation may assume control of the connection. The Evi then minimizes While

ι o minimized, the IM monitors the state of the apphcation. In Step 7, the IM tells the online

service host that the invocation of the SLAP apphcation was successful.

It is at this point that the SLAP apphcation starts communicating with the online

service network node. Technically, the SLAP protocol has been entered because the

supplemental local apphcation, which is not developed or maintained by the online service

is provider and therefore, does not understand details of the online service protocol, is

communicating with the online service. Referring now to Figure 5B, as shown in Step 8, the

SLAP apphcation announces itself to the online service host. The onhne service host responds

with an acknowledgment (Step 9). If the transition between the IM and SLAP apphcation is

successful, the SLAP apphcation takes control of the connection and communicates with the

0 foreign host (Step 10).

When the SLAP apphcation terminates (Step 11), the IM maximizes and awaits a

resume request from the online service host. After the resume request (Step 12) and an

acknowledgment by the IM (Step 13), the user may continue communicating with an online

service host via the IM. The IM and online service host may once again use the online service

5 protocol, rather than the SLAP protocol, to facilitate communications (Step 14). The present invention is unique because it manages transitions between two workstation apphcations, running in a graphical interface environment on a multitasking operating system, so that they may use the same network connection to access information residing on a host computer connected to the network. The transitions are facihtated through a protocol known by the two workstation apphcations and an online service host to which the workstation is connected. The present invention has been described in the form of preferred embodiments, but several modifications and variations to the invention could be made and fall within the scope of the subjoined claims.

Claims

WHAT IS CLAIMED IS:

(1.) A computer system that manages transitions between workstation apphcations said

system comprising: 5 a network node within a wide area network of online service and foreign host

computers; a workstation connected to said network node through a first computer program that

manages a network connection and manages the presentation of information;

a second computer program capable of managing the network connection and o managing the presentation of information to the user; and

a means for transferring network connection information from said first conφuter

program to said second conφuter program whereby said second conφuter program may take

control of said network connection and said first computer program may resume control of

said network connection when said second conφuter program terminates. 5 (2.) The conφuter system of Claim 1, further comprising:

means associated with first conφuter program, second computer program, and said

network node to communicate network connection and program state information.

(3.) The computer system of Claim 1, wherein said first computer program, after

transferring said network connection information enters an inactive state and monitors state of

o said second conφuter program.

(4.) The conφuter system of Claim 1, further comprising:

means associated with said network node for invoking said second computer program

and connecting said workstation to said foreign host conφuter.

(5.) The coπφuter system of Claim 1, wherein said first and said second coπφuter

5 programs operate in a graphical interface, multitasking environment. (6.) A method for transitioning between workstation apphcations, said method comprising

the steps of: providing a first computer program to manage a network connection and to manage

the presentation of information;

providing a second conφuter program to manage a network connection and to manage

the presentation of information;

providing a network node capable of communicating with said first and said second

conφuter programs; providing a means for said first computer program to transfer network connection

information to said second computer program so said second computer program may take control of said network connection;

providing a means for said first computer program to enter an inactive state and

monitor state said second computer program;

providing a means for said first coπφuter program to resume control of said network

connection when said second conφuter program terminates.

(7.) The method of Claim 6, wherein said first and second coπφuter programs operate in a

graphical interface, multitasking environment.

(8.) A system for managing transitions between workstation apphcations comprising:

a wide area network of online service and foreign host computers;

a network node for managing connections to said online service and said foreign host

computers;

a workstation capable of connecting to said network node;

a first computer program at said workstation for managing a connection to and

managing presentation of information from said online service host computer; a second computer program at said workstation for managing a connection to and

managing presentation of information;

a third conφuter program at said network node for managing said connections

whereby said first, said second, and said third computer programs may communicate using a

matching protocol;

said network node causes said workstation to invoke said second conφuter program;

said first conφuter program transfers network connection information to said second conφuter program so said second conφuter program may communicate with said network

node through said connection;

said first computer program monitors state of said second conφuter program so that

said first computer program may resume control of said connection when said second coπφuter program terminates.