Abstract:
A system and method for providing access to a web server on an electronic device positioned within a firewall. A gateway device including a gateway server is provided outside of the firewall. The gateway device includes an IP address that corresponds to the same DNS extension that is used in the DNS name of the web server. When a client device attempts to contact the web server through the DNS name, the request is transmitted to the gateway server, which in turn communicates with the web server.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to web servers on mobile electronic devices. More particularly, the present invention relates to the accessing of web servers on mobile electronic devices that are located behind a firewall. 
     BACKGROUND OF THE INVENTION 
     Currently, network connectivity for mobile devices such as mobile telephones are provided by an operator. The network connectivity can involve the use of systems, such the general packet radio service (GPRS), that allow information to be sent and received across a mobile telephone network. It may be desirable for a server to be placed on that mobile device, where the server can be accessible by clients running on devices on the Internet. 
     In such a system, however, there are currently a number of obstacles that must be overcome. In current operator networks, mobile devices are assigned temporary Internet Protocol (IP) addresses. Client devices attempting to access a web server on such a device must therefore be provided with a way of reaching the server that is independent of the IP address that has been assigned to the mobile device. This constitutes a basic problem of addressability in such a system. 
     Even if a mobile device with a built-in server is assigned a static IP address, however, or if techniques such as dynamic domain name systems (DNS) are used, the server would still be inaccessible. This is due to the fact that operator firewalls typically do not allow connections to be created from a device on the Internet to a mobile device inside the operator&#39;s network. Instead, connections must be created from the inside of the operator&#39;s network and extend outward to the client device. 
     Although there have been attempts to address this accessibility issue, each of these proposed solutions possess serious shortcomings. One proposed solution involves port knocking. With port knocking, when certain firewall port numbers are knocked in a “secret” sequence, then one particular port number is opened for a short period of time. This concept is discussed at www.linuxjournal.com/article.php?sid=6811. Another solution involves the use of a firewall control protocol (FCP), which can enable a third, trusted party to dynamically control the firewall (i.e., which ports are opened, the period of time the ports are opened, which clients are permitted to have the ports opened, etc.) FCP is discussed at www.iptel.org/fcp/ietf-fcp.ppt. For both of these systems, however, there is a requirement that the out-of-network device be given at least some indirect control of the firewall. To satisfy this requirement, operators would need to invest more in their infrastructure and possibly attempt to solve a problem for which there is no correctly existing industry-standard. Moreover, making firewalls dynamically configurable would also result in a need to modify web browsers, which is undesirable. 
     In addition to the above, even if the mobile device possessing the server and the device from which the server is accessed are in the same operator network, there are still no guarantees that the server could be accessed, even if the client knows the temporary IP address. In particular, typical operators do not currently route packets directly between the mobile devices. 
     SUMMARY OF THE INVENTION 
     The present invention addresses the issues discussed above by introducing a gateway that transparently delivers requests from client devices on the Internet to a web server on a mobile device such as a mobile telephone. Similarly, the gateway delivers replies from the mobile web server to the client that initiated the request. 
     The system and method of the present invention provides for a number of advantages over conventional systems. The present permits access to a web server on mobile devices such as mobile phones in currently-existing operator networks, while not requiring any involvement from the operator of the respective device. Additionally, the present invention allows devices such as mobile telephones to become full members of the Internet, without having to wait for the Mobile IPv6 protocol to become available. 
     These and other objects, advantages and features of the invention, together with the organization and manner of operation thereof, will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, wherein like elements have like numerals throughout the several drawings described below. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an overview diagram of a system according to an embodiment of the present invention; 
         FIG. 2  is a perspective view of a mobile telephone that can be used in the implementation of the present invention; 
         FIG. 3  is a schematic representation of the telephone circuitry of the mobile telephone of  FIG. 2 ; 
         FIG. 4  is a representation of a simplified a mobile device, a client device, and a gateway computer/gateway server according to one embodiment of the present invention; 
         FIG. 5  is a flow chart showing the implementation of one embodiment of the present invention; and 
         FIG. 6  is a flow chart showing a process for opening a socket between a client device and a gateway computer in the event that an operator has blocked a particular port to be used. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  shows a system  10  in which the present invention can be utilized, comprising multiple communication devices that can communicate through a network. The system  10  may comprise any combination of wired or wireless networks including, but not limited to, a mobile telephone network, a wireless Local Area Network (LAN), a Bluetooth personal area network, an Ethernet LAN, a token ring LAN, a wide area network, the Internet, etc. The system  10  may include both wired and wireless communication devices. 
     For exemplification, the system  10  shown in  FIG. 1  includes a mobile telephone network  11  and the Internet  28 . Connectivity to the Internet  28  may include, but is not limited to, long range wireless connections, short range wireless connections, and various wired connections including, but not limited to, telephone lines, cable lines, power lines, and the like. 
     The exemplary communication devices of system  10  may include, but are not limited to, a mobile telephone  12 , a combination PDA and mobile telephone  14 , a PDA  16 , an integrated messaging device (IMD)  18 , a desktop computer  20 , and a notebook computer  22 . The communication devices may be stationary or mobile as when carried by an individual who is moving. The communication devices may also be located in a mode of transportation including, but not limited to, an automobile, a truck, a taxi, a bus, a boat, an airplane, a bicycle, a motorcycle, etc. Some or all of the communication devices may send and receive calls and messages and communicate with service providers through a wireless connection  25  to a base station  24 . The base station  24  may be connected to a network server  26  that allows communication between the mobile telephone network  11  and the Internet  28 . The system  10  may include additional communication devices and communication devices of different types. 
     The communication devices may communicate using various transmission technologies including, but not limited to, Code Division Multiple Access (CDMA), Global System for Mobile Communications (GSM), Universal Mobile Telecommunications System (UMTS), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Transmission Control Protocol/Internet Protocol (TCP/IP), Short Messaging Service (SMS), Multimedia Messaging Service (MMS), e-mail, Instant Messaging Service (IMS), Bluetooth, IEEE 802.11, etc. A communication device may communicate using various media including, but not limited to, radio, infrared, laser, cable connection, and the like. 
       FIGS. 2 and 3  show one representative mobile telephone  12  according to one embodiment of the invention. It should be understood, however, that the present invention is not intended to be limited to one particular type of mobile telephone  12  or other electronic device. The mobile telephone  12  of  FIGS. 2 and 3  includes a housing  30 , a display  32  in the form of a liquid crystal display, a keypad  34 , a microphone  36 , an ear-piece  38 , a battery  40 , an infrared port  42 , an antenna  44 , a smart card  46  in the form of a UICC according to one embodiment of the invention, a card reader  48 , radio interface circuitry  52 , codec circuitry  54 , a controller  56  and a memory  58 . Individual circuits and elements are all of a type well known in the art, for example in the Nokia range of mobile telephones. 
     The present invention, depicted in simplified form in  FIG. 4 , operates in a situation where a mobile device  100 , which does not have a fixed IP address, resides behind an operator firewall. The firewall prevents connections from being created from outside of the network to the mobile device  100 , instead only permitting connections to be created from the mobile device  100  to outside of the network. The present invention addresses a situation where a web server  110  is to run on the mobile device, and it is desirable for the server  100  to be accessible to at least one client device  120  (both mobile and/or stationary) on the Internet  28 . 
     According to the present invention, the protocol to be used in the communication between client device  120  on the Internet and the web server  110  on the mobile device  100  is such that the request, when sent by the client device  120  to the web server  110 , contains information about which electronic device  100  the request is intended for. A gateway computer  130  is also set up somewhere on the Internet, outside of the operator firewall. The gateway computer  130  includes a gateway server  140  that listens on two ports. One port is well-known to client devices  120  on the Internet  28  (the HTTP port), while the port is referred to as a specific port. The client device  120 , the mobile device  100  and the gateway computer  130  can all possess circuitry and functionality of the type described in  FIG. 3 . 
     The mobile device  100  containing the web server  110  proceeds to open a connection to the specific port of the gateway server  140 . Each mobile device  100  is assigned a name and is arranged so that DNS lookups for that name result in the IP address of the gateway computer  130  being returned. The gateway server  140  looks at each request arriving from various client devices  120  to the well-known port and uses the content in order to deduce for which mobile device  100  the request is intended. The gateway server  140  then delivers the request over the connection that was opened by the mobile device  100 . The web server  110  on the mobile device  100  will then return a reply over the same connection, and the reply is transmitted to the client device  120 . In this process, it appears as if the web server  110  on the mobile device  100  is directly accessible from any client device  120  on the Internet. Thus, the mobile device  100  has become both addressable and accessible. 
     On implementation of the present invention is generally as follows and is represented in  FIG. 5 . In this particular implementation, the mobile device  100  comprises a mobile telephone, and the protocol is HTTP. In this implementation, a DNS is configured so that all DNS lookups ending in a particular extension, such as “name.mu”, result in the IP address of the gateway computer. For illustrative purposes only, it is assumed that the IP address is 10.20.30.40. In practice, this means that lookups such as, for instance, alice.name.mu and bob.name.mu result in an IP address of 10.20.30.40. 
     As discussed earlier, the gateway computer  130  includes a gateway server  140 , which listens to the usual HTTP port  80 , and, for example to port  2050 . On the mobile telephone, the web server  110  is running at step  500 , and it listens to the usual HTTP port  80 . However, this web server  110  is not accessible by anyone outside of the mobile telephone due to the problems discussed above. Furthermore, another process, referred to herein as the connector, is running, The connector opens a socket to port  2050  at step  505 . As part of the opening of that socket, the connector declares the identity of the mobile telephone. As part of this opening sequence, the gateway server  140  learns the name of the mobile telephone. In this example, the mobile telephone is known as “alice.” 
     In the event that someone on the Internet attempts to browse to alice.name.mu, the following sequence of events occurs. The browser on the client device  120  performs a lookup for alice.name.mu at step  510 . This lookup returns 10.20.30.40 as a result at step  515 , which is the IP address of the gateway server  140 . The browser proceeds to the HTTP port  80  on 10.20.30.40 and to transmit a regular HTTP request at step  520 . The HTTP request header includes alice.name.mu in its host field. 
     From the value of the host field, the gateway sever deduces the recipient for the request at step  525 . If the device known as alice has opened a connection to the gateway server  140 , then the gateway server  140  sends the request to the mobile telephone over that connection at step  535 . If the mobile telephone has not opened a connection to the gateway server, then the gateway server  140  responds with the appropriate error reply at step  530 . When the request reaches the connector on the mobile telephone, the connector transmits it to the web server  110  running on the mobile telephone at step  540 . When the web server  110  replies, the connector sends the reply back to the gateway server at step  545 . The gateway server then proceeds to send it back to the browser that made the initial request at step  550 . Therefore, to the individual using the browser, it appears as if the mobile telephone was directly accessible using the url alice.name.mu. 
     The solution depicted in  FIG. 5  relies upon the mobile device  100  being able to open a TCP/IP socket from the mobile device  100  to the gateway server  140 . However, an operator could prevent this creation from occurring by blocking the port that is used in the communication between the mobile device  100  and gateway computer  130 .  FIG. 6  is a flow chart showing a process for addressing this issue according to one embodiment of the present invention. In this process, it is assumed that the operator does not block every potential port, and that port  80  is not blocked by the operator. 
     As depicted in  FIG. 6 , the mobile device  100  attempts to open a socket to the gateway server  140  at step  600 . If this succeeds, then no additional action is necessary and the process of  FIG. 5  proceeds as discussed above. This is represented at step  610 . If the attempt fails, this may be due to the fact that the operator has blocked the desired port in its firewall. In response, the mobile device  100  opens an HTTP connection to the gateway computer  130  using the regular web port  80  at step  620 . This step is likely to succeed, as it is extremely unlikely that an operator would block this port. At step  630 , the mobile device  100  transmits an HTTP request using a particular URL and informs the gateway server  140  that a particular port can no longer be used. At step  640 , the gateway server  140  creates another incoming socket using a different port and, in the HTTP reply, informs mobile device  100  of the port number. The process is then repeated until an open port is found, at which time a socket is opened. This system makes it difficult, if not impossible, for an operator to prevent the connectivity solution of the present invention to be implemented unless all ports were blocked, which would render 2G and 3G networks meaningless unless a traffic analysis was performed on every connection. 
     The present invention is described in the general context of method steps, which may be implemented in one embodiment by a program product including computer-executable instructions, such as program code, executed by computers in networked environments. 
     Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Computer-executable instructions, associated data structures, and program modules represent examples of program code for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represent examples of corresponding acts for implementing the functions described in such steps. 
     Software and web implementations of the present invention could be accomplished with standard programming techniques, with rule based logic, and other logic to accomplish the various database searching steps, correlation steps, comparison steps and decision steps. It should also be noted that the words “component” and “module” as used herein, and in the claims, is intended to encompass implementations using one or more lines of software code, and/or hardware implementations, and/or equipment for receiving manual inputs. 
     The foregoing description of embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the present invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the present invention. The embodiments were chosen and described in order to explain the principles of the present invention and its practical application to enable one skilled in the art to utilize the present invention in various embodiments and with various modifications as are suited to the particular use contemplated.