# Patent

## Title
Real-time streaming protocol gateway and proxy for serving and caching static media over a low bandwidth connection

## Abstract

A system and method to support the transmission of static media, originating from an HTTP source, as a Real-Time Streaming Protocol (RTSP) stream to a caching proxy. A server-side gateway accepts RTSP requests, loads a requested resource from the HTTP source, and streams requested portions of a file via RTSP. A RTSP proxy caches received portions of media to avoid re-requesting those portions. The RTSP proxy may receive a RTSP TEARDOWN command to trigger removal of cached media and passes the RTSP TEARDOWN command to the server-side gateway. Further, the server-side gateway may receive a RTSP TEARDOWN command to trigger the server-side gateway to remove media loaded from the HTTP source.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of and claims the benefit of prior filed U.S. application Ser. No. 12/138,473, filed on Jun. 13, 2008, titled REAL-TIME STREAMING PROTOCOL GATEWAY AND PROXY FOR SERVING AND CACHING STATIC MEDIA OVER A LOW BANDWIDTH CONNECTION, incorporated herein by reference.


BACKGROUND OF THE INVENTION
The present invention relates to a Real-Time Streaming Protocol (RTSP) gateway and proxy for serving and caching static media over a low bandwidth connection. More particularly, the present invention is directed to a system and method to support the transmission of static media, originating from an HTTP source, as an RTSP stream to a caching proxy.
In telephony, Interactive Voice Response (IVR) is a technology that allows a computer to detect voice and touch tones in a telephone call.
Many companies employ systems based on IVR technology to process and route telephone calls originating from their respective customers. Examples include telephone banking, televoting, and credit card transactions. IVR systems are typically used to service high call volumes, reduce cost and improve the customer experience.
If a customer dials a telephone number that is answered by an IVR system, the system executes an application that responds to the customer/caller with pre-recorded or dynamically generated audio files. These audio files explain the options available to the caller and direct the caller on how to proceed. The caller selects an option by using spoken words or Dual-Tone Multi-Frequency (DMTF) tones, e.g., telephone keypad touch tones.
Modern IVR applications are structured similar to World Wide Web pages, using languages such as VoiceXML. Other languages may include, for example, SALT or T-XML.
Since many companies do not have their own IVR platforms, they typically turn to outsourcing companies or vendors to either host their VoiceXML application or manage the application as a whole. An example of such a hosted environment is shown in FIG. 1.
The hosted environment shown in FIG. 1 may include end user devices, such as a mobile device 105 or a land-line phone 110; hosted vendor systems 115; and client systems 120. The mobile device 105, such as a cellular phone, PDA, or iPhone, and/or the land-line phone 110 may communicate with the hosted vendor systems 115 via a telephony interface 125. The telephony interface 125, in turn, interacts with a VoiceXML browser 130, a MRCP TTS Server 135, and a MRCP Speech Recognition Server 140, all of which are part of the hosted vendor systems 115.
The VoiceXML browser 130 may be an extension of a web browser that presents an interactive voice user interface to the user and that operates on pages that specify voice dialogs. These pages may be written in VoiceXML language, which is the W3C's standard voice dialog markup language, but other proprietary voice dialog languages may be used. The VoiceXML browser 130 may present information aurally, using pre-recorded audio file playback or using Text-To-Speech (TTS) software to render textual information as audio. Further, the VoiceXML browser 130 may obtain information from the end user of the mobile device 105 and/or the land-line phone 110 by speech recognition and keypad entry, e.g., DTMF detection.
The VoiceXML browser 130 interacts with the MRCP TTS Server 135 and the MRCP Speech Recognition Server 140. MRCP stands for Media Resource Control Protocol, which is a communication protocol that allows speech servers to provide various speech services, such as speech recognition, speech synthesis, and TTS to its clients. The MRCP TTS Server 135 provides ITS services to its clients, and the MRCP Speech Recognition Server 140 provides speech recognition services to its clients.
Computer Telephone Integration (CTI) data are sent from the hosted vendor systems 115 to a CTI Management Server 145. CTI is a technology that allows interactions on a telephone and a computer to be integrated or coordinated. As contact channels have expanded from voice to email, web, and fax, CTI has expanded to include the integration of all customer contact channels (voice, email, web, fax, etc.) with computer systems. Common functions that may be implemented using CTI are, for example, call routing, call information display with or without using calling line data, phone control (answer, hang up, hold, conference, etc.), automatic dialing and computer-controlled dialing, etc.
Furthermore, application requests are sent from the VoiceXML Browser 130 to a VoiceXML Application Server 150, and the requested VoiceXML application is delivered from the VoiceXML Application Server 150 to the VoiceXML Server 130. The CTI Management Server 145 and the VoiceXML Application Server 150 are both part of the client systems 120.
More and more people use intelligent mobile devices, such as cellular phones, PDAs, or iPhones, as a means of communication. These intelligent mobile devices become more and more sophisticated due to, for example, increased computing power or memory capacity, and due to, for example, the availability of mobile Software Development Kits (SDKs), such as Java Platform, Micro Edition (Java ME) or Apple's iPhone SDK. This may lead to decreased reliance on teleservices companies that are built on standard telephony technology. More particularly, this may lead to decreased reliance on hosted environments for IVR applications, for example.
BRIEF SUMMARY OF THE INVENTION
The present invention, in exemplary embodiments, overcomes the above disadvantages and other disadvantages not described above. Also, the present invention is not required to overcome the disadvantages described above, and an exemplary embodiment of the present invention may not overcome any of the problems described above.
Thus, in one aspect, the present invention is directed to a method for supporting transmission of static media, originating from an HTTP source, as a Real-Time Streaming Protocol (RTSP) stream to a caching proxy, the method comprising accepting RTSP requests, loading a requested resource from the HTTP source, and streaming requested portions of a file via RTSP.
In another aspect, the present invention is directed to a computer-readable medium comprising instructions for supporting transmission of static media, originating from an HTTP source, as a Real-Time Streaming Protocol (RTSP) stream to a caching proxy, wherein the instructions are for accepting RTSP requests, loading a requested resource from the HTTP source, and streaming requested portions of a file via RTSP.
In yet another aspect, the present invention is directed to a system to support transmission of static media, originating from an HTTP source, as a Real-Time Streaming Protocol (RTSP) stream to a caching proxy, wherein the system comprises a server-side gateway and a RTSP proxy. The server-side gateway accepts RTSP requests, loads a requested resource from the HTTP source, and streams requested portions of a file via RTSP. The RTSP proxy caches received portions of media to avoid re-requesting the received portions.



BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
In the following section, the invention will be described with reference to exemplary embodiments illustrated in the attached Figures, in which:
FIG. 1 illustrates a hosted environment for IVR applications as it may be known in the related art;
FIG. 2 illustrates a Mobile Voice Self Service (MVSS) system in accordance with an exemplary embodiment of the present invention;
FIG. 3 illustrates an MVSS VoiceXML Navigation situation in accordance with an exemplary embodiment of the present invention;
FIG. 4 illustrates incorporation of multimedia data into MVSS in accordance with an exemplary embodiment of the present invention;
FIG. 5 illustrates a method in accordance with an exemplary embodiment of the present invention; and
FIG. 6 illustrates a method in accordance with another exemplary embodiment of the present invention.



DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings.
Given the rapidly increasing processing power of mobile devices and the availability of mobile SDKs, a hosted application browser of the related art, such as a hosted VoiceXML browser, may be moved directly to an end user's mobile device. In other words, an application browser, such as a VoiceXML browser, and other, associated components may be deployed as a mobile application and implemented on the mobile device to allow a VoiceXML application to be processed directly on the mobile device. This concept may also be known as Mobile Voice Self Service (MVSS).
MVSS may provide the benefit of reduced cost or, in the case of simple applications, no hosting cost to companies, for example. In addition, the end-user features that MVSS provides may allow applications to become more user-friendly.
FIG. 2 illustrates an MVSS system in accordance with an exemplary embodiment of the present invention.
As shown in FIG. 2, a mobile device 205 communicates with client systems 210 and media resource systems 215 of a vendor. The mobile device 205 may include an Application Browser 220 that interacts with a Call Data Manager 225 and a Media Resource Gateway 230. The Call Data Manager 225 and the Media Resource Gateway 230 may also be included in the mobile device 205. These components may utilize the mobile device's 205 mobile broadband or wireless connection to communicate with the client systems 210 or the service vendor's media resource systems 215. The mobile device 205 may be, for example, a cellular phone, a PDA, or an iPhone, and may operate, for example, in a CDMA or GSM network. The mobile device 205 may also include a GPS component 235 to provide, for example, location-based services to the user of the mobile device 205.
As is the case in the related art, the client systems 210 may include a VoiceXML Application Server 240 and a CTI Management Server 245. The vendor's media resources systems 215 may include an MRCP Speech Recognition Server 250, a Media Resource Gateway 255, and a MRCP TTS Server 260.
The Application Browser 220 of the mobile device 205 may be a VoiceXML 2.1 compliant browser with a minimal memory footprint and minimal processing overhead. Unlike the VoiceXML browsers used in a hosted environment in the related art, the Application Browser or VoiceXML browser 220 may only need to be able to handle one call. Therefore, the required processing power is significantly reduced. In addition, the VoiceXML browser 220 may be able to handle a majority of the call flow required to provide an IVR application to the user of the mobile device 205. The VoiceXML browser 220 may send application requests to the VoiceXML Application Server 240, and the requested VoiceXML application may be delivered from the VoiceXML Application Server 240 to the VoiceXML browser 220.
The Call Data Manager 225 may communicate important telephony events to the client systems 210, in particular to the CTI Management Server 245. Such telephony events may include, for example, set up, deliver (ringing), establish (answer), clear (hang up), end, hold, retrieve from hold, conference, transfer, forward, etc. When a legitimate call is being processed on the mobile device 205, the call data provided by the Call Data Manager 225 may be used, in conjunction with data of the VoiceXML Application Server 240, to authorize access to advanced MRCP features. The advanced MRCP features may include automatic speech recognition (ASR) that may be provided by the MRCP Speech Recognition Server 250 or Text-To-Speech (TTS) that may be provided by the MRCP TTS Server 260, for example. Proper authentication may be important because MRCP features may be charged per transaction by the vendor. Also, the Call Data Manager 225 may be important with respect to transfers. Transfers that usually depend on a carrier's advanced features may need to be implemented by other means, so it may be necessary for User-to-User Information (UUI) and other call data to be transferred out-of-band.
The Media Resource Gateway 255 may provide advanced services, such as ASR or TTS to the application, by bridging communication between the VoiceXML browser 220 and the MRCP services. As part of authorizing communication to media resources, MRCP requests from the VoiceXML browser 220 may be directed through the Media Resource Gateway 255. The gateway layer may handle authentication and then host the MRCP communication through the established channel. If the mobile device 205 is capable of processing speech or generating TTS on its own, resources not requiring vendor-specific handling may be passed off to the mobile device 205 by the Media Resource Gateway 230, thereby saving the application provider additional advanced service fees.
To facilitate the configuration of MVSS components prior to running a VoiceXML document, a Mobile Voice Self Service configuration file may be used. This file may be an xml-based configuration file that contains the configuration settings of the Media Resource Gateway 230 and the Call Data Manager 225 as well as the URL of the intended VoiceXML target.
Having a unique file type for voice applications targeted to mobile devices may also be useful in allowing seamless integration of MVSS into a web environment. A mobile device may automatically launch the MVSS application when the user follows a link that provides MVSS content. The format of such a file may be defined, published and validated via standard xml validation methods.
Simple blind transfers may be accomplished by allowing the MVSS application to access the phone's system APIs (Application Programming Interfaces) to simply dial the transfer number. More complicated transfers may require functions that may be unavailable within the realm of the mobile device's capabilities on the mobile carrier's network. To implement these transfers may require dialing a toll-free number that has carrier-advanced features and then utilizing call data to execute the transfer.
The following may be exemplary applications of MVSS that may be advantageous to, for example, the end users, vendors, service providers, companies and clients involved.
With respect to access to IVR applications, in the case of MVSS, the user may be allowed to access applications via web URLs rather than phone numbers. A client's site may list individual URLs for each subsection of their application, giving the user direct access to billing or technical support features, without the need for the client to have individual phone numbers for each service. Having direct access to the VoiceXML interpretation allows the user to easily “pause” the IVR, and it may be relatively simple to provide a complete range of controls a user would normally be accustomed to with other media, such as fast forward, rewind, etc.
Instead of having to rely on the application's menu repeat options, the user may interact with the browser instructing it to scan through a prompt in reverse, go back to the beginning of the current prompt or menu, or even go to a previous menu and either accept the user's original response again or provide new input. To support such features, when it comes to application reporting, it may be beneficial to create new VoiceXML events that the browser can handle, so reporting can accurately reflect the user's navigation. FIG. 3 shows an exemplary illustration of MVSS VoiceXML Navigation.
Having direct access to the call flow data may allow implementing user-defined hotkeys or “bookmarks” in a VoiceXML application. If the user would like to return to a portion of an application at a later time, he or she may press a hotkey capture button, which may then suspend the running VoiceXML application. The MVSS browser may store the current state and the input required to reach that state. After speaking or entering a bookmark identifier, the application may resume normally. At a later time, the user may request access to the bookmark, and this may instruct MVSS to load the application and automatically proceed to the bookmarked state if modifications to the applications do not prevent it. In the case where the application has been modified, MVSS may provide a message to the user indicating the bookmark needs to be updated; present the user with the prompt where the application changed; and wait for the user to indicate that he or she has once again reached the point in the application the user wishes to bookmark.
Location-based services is another area in which having the MVSS browser running directly on the mobile device may be of advantage. Providing location-based information to customers may mean to add more value in the mobile realm. Rather than relying on complicated data exchanges to determine the location of the caller, the browser may directly access the device's GPS or tower based coordinates and pass them on to the application server. This may all be done as part of the initial request to the application server. Self-service applications may then be catered for the caller's current location prior to even the first prompt.
Multimedia resources, as illustrated, for example, in FIG. 4, may be referenced within the VoiceXML application, allowing the mobile device to display supplemental data during the progress of the call. This may be utilized by providing an image of the caller's current billing statement when the caller requests payment information; by providing a video clip of the steps required to reset a satellite receiver when the caller is requesting technical support; or even by launching a web page with a registration form when the caller wants to enroll in some special program. There may also be the branding aspect that may be important to many companies, so a company logo, customer notifications, or advertising may be displayed on the mobile device while working with their IVR.
In the VoIP world, it may be common for a conference call to be presented along with video conferencing or a shared desktop for a presentation. MVSS may add functionality in the voice self-service world because the multimedia may also interact back with the IVR. For example, if the caller has a question about their bill, MVSS may display the caller's recent billing statement on the screen and allow the user to select the billing line-item the caller has a question about and say “What is this charge”? Again, due to the fact that the VoiceXML interpretation is happening locally on the caller's phone, the act of selecting an item on the screen may be passed to the browser as input without complex data exchanges. This sort of interaction may be simplified because MVSS is just a single system that accepts multiple forms of input.
MVSS technology may be an industry standard that may be implemented by mobile device builders as part of their devices' core features.
There may be several versions of MVSS to support various mobile device architectures. Open development environments like Java ME may aid in that sort of development, but each device may require its own special development for its unique features or hardware.
FIG. 5 illustrates a method in accordance with an exemplary embodiment of the present invention. In step 510, an application browser that is implemented on an MVSS mobile device may request an application from an application server. The application browser may be a VoiceXML browser; the application may be a VoiceXML application; and the application server may be a VoiceXML application server.
In step 520, a call data manager may provide call data. The call data manager may also be implemented on the MVSS mobile device. The call data, in conjunction with data from the application server, may authorize access to advanced MRCP services such as ASR or TTS.
In step 530, the advanced MRCP services may be provided to the application that was requested by the application browser. The advanced MRCP services may be provided by a media resource gateway.
In another exemplary embodiment of the present invention, a system and method are provided to support the transmission of static media, originating from an HTTP source, as a Real-Time Streaming Protocol (RTSP) stream to a caching proxy. The exemplary system and method may be used to conserve bandwidth by supporting the transmission of static media to systems that are likely to require only a portion of the media.
Therein, as shown in FIG. 6, a server-side gateway may accept 610 RTSP requests, may load 620 the requested resource from the HTTP source, and may stream 630 the requested portions of the file via RTSP. A RTSP proxy may cache 640 received portions of the media to avoid re-requesting those portions of the media. Discrete segments of the received media may be coalesced into a single segment when those segments are adjacent.
A RTSP TEARDOWN command received by the RTSP proxy may trigger the removal of the cached media. The RTSP proxy may pass the RTSP TEARDOWN command to the server-side gateway.
A RTSP TEARDOWN command received by the server-side gateway may trigger the gateway to remove the media which was loaded from the HTTP source. Concurrent requests for the same media may result in the server-side gateway maintaining either separate copies of the same HTTP media or a shared copy. This behavior may be dependent upon media-specific configurations.
As will be recognized by those skilled in the art, the innovative concepts described in the present application can be modified and varied over a wide range of applications. Accordingly, the scope of patented subject matter should not be limited to any of the specific exemplary teachings discussed above, but is instead defined by the following claims.

## Claims

1. A method comprising:
supporting transmission of static media, originating from an HTTP source, as a Real-Time Streaming Protocol (RTSP) stream to a caching proxy, wherein the static media is based on a location of a client sending RTSP requests.

2. The method as claimed in claim 1, further comprising caching received portions of media to avoid re-requesting the received portions.

3. The method as claimed in claim 2, wherein discrete segments of received media are coalesced into a single segment when the discrete segments are adjacent.

4. The method as claimed in claim 1, further comprising:
receiving a RTSP TEARDOWN command in a RTSP proxy to trigger removal of cached media; and
passing the RTSP TEARDOWN command from the RTSP proxy to a server-side gateway.

5. The method as claimed in claim 1, further comprising loading a requested resource from the HTTP source, and receiving a RTSP TEARDOWN command in a server-side gateway to trigger the server-side gateway to remove media loaded from the HTTP source.

6. The method as claimed in claim 1, further comprising, if same media is concurrently requested, maintaining one of separate copies and a shared copy of the same media.

7. The method as claimed in claim 6, wherein the maintaining of one of separate copies or a shared copy of the same media is dependent upon media-specific configurations.

8. A non-transitory computer-readable storage medium:
supporting transmission of static media, originating from an HTTP source, as a Real Time Streaming Protocol (RTSP) stream to a caching proxy, wherein the static media is based on a location of a client sending RTSP requests.

9. The non-transitory computer-readable storage medium as claimed in claim 8, further comprising caching received portions of media to avoid re-requesting the received portions.

10. The non-transitory computer-readable storage medium as claimed in claim 9, wherein discrete segments of received media are coalesced into a single segment when the discrete segments are adjacent.

11. The non-transitory computer-readable storage medium as claimed in claim 8, further comprising:
receiving a RTSP TEARDOWN command in a RTSP proxy to trigger removal of cached media; and
passing the RTSP TEARDOWN command from the RTSP proxy to a server-side gateway.

12. The non-transitory computer-readable storage medium as claimed in claim 8, further comprising receiving a RTSP TEARDOWN command in a server-side gateway to trigger the server-side gateway to remove media loaded from the HTTP source.

13. The non-transitory computer-readable storage medium as claimed in claim 8, further comprising, if same media is concurrently requested, maintaining one of separate copies and a shared copy of the same media.

14. The non-transitory computer-readable storage medium as claimed in claim 13, wherein the maintaining of one of separate copies or a shared copy of the same media is dependent upon media-specific configurations.

15. A system comprising:
a server-side gateway operable to:

support transmission of static media, originating from an HTTP source, as a Real-Time Streaming Protocol (RTSP) stream to a caching proxy, wherein the static media is based on a location of a client sending RTSP requests.

16. The system as claimed in claim 15, further comprising an RTSP proxy operable to cache received portions of media to avoid re-requesting the received portions, wherein the RTSP proxy is operable to receive a RTSP TEARDOWN command to trigger removal of cached media; and wherein the RTSP proxy is operable to pass the RTSP TEARDOWN command to the server-side gateway.

17. The system as claimed in claim 15, wherein the server-side gateway is further operable to load a requested resource from the HTTP source, and to receive a RTSP TEARDOWN command to trigger the server-side gateway to remove media loaded from the HTTP source.

18. The system as claimed in claim 15, wherein, if same media is concurrently requested, the server-side gateway is operable to maintain one of separate copies and a shared copy of the same media.