Patent Publication Number: US-2005137838-A1

Title: Dial-up resource simulator

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a dial-up resource simulator used to enable a test application which tests a data service.  
      2. Description of the Related Art  
      Providers of data services, such as email, MMS, SMS or even digital cellular or dial-up service providers must test their services to ensure quality. This testing may be achieved by running a test application, which may be developed by and purchased from another party. While developing the test application, the test application must be run over the network for which it is intended to be used.  
       FIG. 1  is a block diagram of a conventional system  100  to enable a test application  112 . A computer  110  runs the test application  112 . The test application  112  is connected to a digital cell phone  120 , which connects the test application  112  to a wireless receiver  130  which connects with a data service  140  via a network  135 .  
      As illustrated in  FIG. 1 , the system  100  includes a network  135  between the wireless receiver  130  and the data service  140 . The network  135  may be an IP network layered on top of a carrier network or a non-IP digital wireless carrier network.  
      As illustrated in  FIG. 1 , the system  100  includes a wireless connection between the test application  112  and the data service  140 . Although not illustrated, a wired connection is also possible in which the digital cell phone  120  and wireless receiver  130  are replaced with modems which connect via a conventional telephone line.  
       FIG. 2  is a flow diagram of a method of enabling the test application  112  of  FIG. 1 . First, a connection is established between the test application  112  and the modem (wired) or digital cell phone  120  (wireless) (S 100 ).  
      Next, in the case of an IP based connection, a connection is established between the test application  112  and the data service  140  (S 110   a ). This connection may be a GPRS network, when making an IP connection over a wireless link, or a standard modem connection on a switched phone network, when making an IP connection over a wired link. In either case, the connection is typically achieved via Point to Point Protocol (PPP). Alternately, in the case of a non-IP based connection, the test application  112  interacts with a digital cellular data service (S 110   b ). This digital cellular data service is provided by the digital wireless carrier network (such as a GSM, CDMA, or TDMA network), without requiring an IP network. Next, the test application  112  exercises the data service  140  (S 120 ).  
      The conventional approach has the following disadvantages. In the case of testing wireless services, there are acute dependencies on the existence of a wireless network. A wireless network for services testing is expensive to deploy and maintain. Use of existing services through commercial service providers is also expensive and limited by non-deterministic behavior. Also, wireless and wired services may not be readily available for development and testing. For example, some services (such as GPRS) may only be available in European geographies while development is done in the United States, requiring troublesome development and testing on remote systems with limited physical contact to the systems. In the past, testing of wireless services has required the purchase of mobile devices and SIM cards for those devices. Testing has been done by locating hardware in geographies with the wireless services and managing those devices remotely.  
     SUMMARY OF THE INVENTION  
      Accordingly, selected embodiments of the present invention overcome the above disadvantages of the conventional system.  
      The present invention could possibly provide an apparatus to reduce costs when evaluating an application which tests a data service over a dial-up connection.  
      The present invention also could possibly provide a simulator to simulate various dial-up devices.  
      Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.  
      The foregoing and other advantages may be achieved by providing an apparatus to enable an application which tests a data service, including a dial-up resource simulator to simulate a dial-up resource to connect the application and the data service.  
      The foregoing and other advantages may also be achieved by providing a method of enabling an application which tests a data service, including simulating a dial-up resource to connect the application and the data service with a simulator.  
      The foregoing and other advantages may also be achieved by providing a system including a test application to test a data service, and a simulator to simulate a dial-up resource to connect the test application and the data service. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      These and other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings of which:  
       FIG. 1  is a block diagram of a conventional system to enable a data service test application;  
       FIG. 2  is a flow diagram of a conventional method of enabling the data service test application of  FIG. 1 ;  
       FIG. 3 . is a block diagram of a system to enable a data service test application according to embodiments of the present invention; and  
       FIG. 4  is a flow diagram of a method of enabling the data service test application of  FIG. 4 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      Reference will now be made in detail to the present preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.  
       FIG. 3  is a block diagram of a system  1  to enable a data service test application  12  according to the embodiments of the present invention. As illustrated, the test application  12  is a computer program, run by a computer  10 . The test application  12  is connected to a dial-up resource simulator  20 . The simulator  20  simulates the function of a dial-up resource such as a digital cell phone, an AT modem, or any device that utilizes modem style AT commands which connects the test application  12  to a data service  32  or a digital cellular data service emulator  34  (described below). A dial-up resource is any type of device, supporting an AT-style command set, which interfaces a computer with an on-demand switched network (either wired or wireless). The interface is achieved via the use of AT commands, which are commands, typically beginning with “AT”, to control a dial-up resource by querying and setting registers internal to the dial-up resource. The simulator  20  includes a responder  22 , a connector  24 . The responder  22  includes a digital cellular data service emulator  34 . The responder  22  may be the AT-command simulator, or any other device that can receive register initialization and query commands (such as AT commands) from the test application  12  and simulate the response of a dial-up resource to the commands.  
      Pseudo-TTY units  42 ,  44  connect the test application  12  with the responder  22 . The pseudo-TTY units  42 ,  44  may be a software serial device such as Unix-style ptty devices, or any other software serial device that can receive and transmit serial data.  
      The digital cellular data service emulator  34  may be a program, or any device that emulates a digital cellular data service, such as SMS, that is controlled through AT-style commands. Digital cellular data services are defined as services provided by a digital cellular service provider that are internal to the digital cellular network, and not IP connection based,  
      The connector  24  establishes a connection to an IP network  30  which then connects to an IP data service  32 . The connector  24  may be a known device such as the pppd simulator, or any other utility that can establish an IP network connection between the test application  12  and the data service  32 .  
      This simulated connection may be achieved, for example, if the connector  24  is a pppd wrapper. A pppd wrapper gives the appearance of the pppd utility to the test application  12  to thereby establish an IP network connection to connect the test application  12  with the network  30  and simulate the function of an AT modem or other dial-up resource. The utility pppd is a known utility for establishing a network connection via a dial-up resource. The present invention is not limited to wrapping pppd, but may also simulate other utilities, such as SLIP or other serial line internet protocol utilities.  
      The listed examples with respect to the responder  22 , the connector  24  and the pseudo-TTY units  42 ,  44  are not limiting, and any apparatus to achieve the above-described functions of these elements may be used.  
      The data service  32  may be, for example, an HTTP service, a mail service, a news service, or an MMS (Multimedia Message Service) service. The digital cellular data service emulator  34  may be a modeling program of the actual service, SMS (Short Message Service) service for example. However, these are only examples, and any service which provides access to, transmission of, or searching of data is possible.  
      The simulator  20  may simulate the function of any AT-style modem or dial-up resource, thereby simulating either wired or wireless connections. Specifically, the connection via the network  30  simulates either a wired or a wireless connection and the connection between the connector  24  and the digital data service  34  simulates purely a wireless connection on the digital wireless carrier network. The network  30  may be a local area network (LAN), the Internet, or any global communications network. Although the concept of a “simulator” is well known, the application of this concept to simulate a dial-up resource as described herein is not.  
       FIG. 4  is a flow diagram of a method of enabling the data service test application  12  of  FIG. 3 . First, a connection is established between the test application  12  and the dial-up resource simulator  20  (S 10 ). The operation S 10  includes two sub-operations. First, the test application  12  generates AT commands so that the test application  12  may initialize a dial-up resource, establish and authenticate the provider of the dial-up services, and authenticate the identity of the user of the test application  12  (S 10 A). Then, the responder  22  simulates the response of an actual dial-up resource to the AT commands and sends this response back to the test application  12  via the pseudo-TTY units  42 ,  44 . The response may be either static or dynamic.  
      Next, in the case of an IP connection, a network connection is established between the test application  12  and the data service  32  or the emulator  34  (S 20 ). This is achieved by giving the appearance that pppd is run. Unlike an actual pppd connection, local networks may be used in the present embodiments. The network connection may be, for example, an IP connection or any simulated cellular data network connection. These are just examples, however, any type of connection is possible.  
      In the case of a non-IP connection, operation S 20  is not necessary.  
      Next, the test application  12  exercises the data service  32  or the emulator  34  (S 30 ). This exercising may be, for example, testing how long it takes to post or receive a SMS message, create or receive an MMS message, pull email from an email server or determine whether the appropriate content is provided.  
      The discussion of  FIG. 4  has shown illustrative examples, however, the present invention is not limited to these examples. For example, the connection between the test application  12  and the simulator  20  may be achieved by any command system that permits querying and setting state registers of a dial-up resource to establish an IP network. Instead of giving the appearance of pppd in operation S 20 , the connector  24  may give the appearance of establishing a SLIP connection. Numerous ways of exercising the data service other than those listed are also possible.  
      By enabling the test application  12  according to these embodiments, it is also possible to evaluate the test application  12  itself.  
      The present embodiments have the following advantages. First, the dial-up resource simulator minimizes the dependency on a dial-up, such as wireless, network, making it possible to do local testing with less expensive hardware than the needs of a dial-up network. Also, the dial-up resource simulator minimizes the amount of development and testing on expensive, remotely located hardware and the additional costs of purchasing dial-up services. The dial-up resource simulator also enables the emulation of large numbers of devices that would otherwise be economically infeasible.  
      Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.