Abstract:
The invention provides a test phone whereby the test phone comprises means to communicate to a server, means to generate SIP signaling towards the server, whereby the test phone by means for SIP signaling may request the server to set-up a test call using specific resources for routing said test call.

Description:
TECHNICAL FIELD 
       [0001]    In the telecommunications world, there exists a need to test devices of a telecommunication network, either regarding their overall functionality or the quality they provide. The invention relates to an improved system allowing to use Phones using SIP as a Test phone. 
       BACKGROUND 
       [0002]    Telecommunication exchanges, wireline as well as wireless exchanges, are equipped with a test position. 
         [0003]    Typically, test position comprises an I/O device, an instrument box and a test phone. 
         [0004]    The I/O device can be used to specify and retrieve details for the wanted test. 
         [0005]    The instrument box can be used to connect measurement equipment and/or to receive or send tones, e.g. to generate in-band information. 
         [0006]    The test phone can be a mobile or a fixed phone. 
         [0007]    Typically, operators use the test position to check the call and routing analysis, to check the general speech quality, to check the performance and accessibility of specific resources by routing the call through these resources, and to monitor an ongoing call involving other parties to access the speech quality. 
         [0008]    Such checks and analysis comprise an increasing value since premium services are offered typically along with certain warranted characteristics. 
         [0009]    Traditionally, for the purposes stressed above the exchange needs to support PRA signaling (Primary Rate Access) towards the test phone. 
         [0010]    However, in typical soft switch architecture, the exchange is split into one or more servers and one or more media gateways. 
         [0011]    A server is responsible for call handling connecting to one or more media gateways, while the one or more media gateways are actually handling the payload data. 
         [0012]    Typically, the servers are located centralized whilst the media gateways are located de-centralized. 
         [0013]    By splitting up the architecture, it is now impossible to connect devices concerning payload data such as test phones and/or I/O devices towards the server unless the server provides extra hardware. 
         [0014]    On the other hand although it would be possible to connect these devices towards a media gateway, the media gateway does not support call set-up and call control since these functionalities are shifted towards the server unless the media gateway provides extra hardware. 
         [0015]    A present solution to this problem encompasses the use of a mobile phone as a test phone. 
         [0016]    However, using a mobile phone leads to several limitations, making it a complement rather than replacement of a fixed test phone. 
         [0017]    Such limitations include for example, that a mobile phone will only work when the radio network works, that the voice quality is limited to the voice quality of the mobile network, that the capabilities of the test phone are limited to the capabilities of the mobile phone, . . . . 
         [0018]    Another solution used so far encompasses the use of a test phone in a remote exchange. 
         [0019]    However, using a remote test phone leads to other disadvantages of which two are mentioned exemplary, i.e. that it is not possible to request certain resources to be used within a test call and that such remote test phones rely on the availability of the remote control. 
         [0020]    Operators need a subjective way of testing the pay load connectivity (voice quality) which is independent from the radio network performance. 
       SUMMARY 
       [0021]    It is the object to obviate at least some of the above disadvantages and provide an improved system and methods therefore which allows for greater flexibility. 
       BASIC CONCEPT 
       [0022]    The basic idea of this invention is it to use a test phone using SIP. 
         [0023]    Typically, Soft switch servers are equipped with a Media Gateway Control Function (MGCF), which allows for interworking between SIP and ISUP/BICC signaling networks. 
         [0024]    In providing a test phone using SIP certain advantages may be achieved. 
         [0025]    For example, using a test phone using SIP obviates an implementation of PRA in a Multi-Mediagateway (M-MGw). 
         [0026]    Furthermore, it is also possible to use soft phones as a test phone using SIP, hence no new hardware is needed. 
         [0027]    In addition, the test phone using SIP and a I/O-device functionality may be integrated in one work place and even more into one device. 
         [0028]    Furthermore, such a test phone using SIP would also provide for execution of automatic test cases through SIP application servers. In this case the test phone using SIP could instruct an SIP application server to perform tests remotely, on request or even in a scheduled way. The results can either be stored and /or provided back to the instructing test phone or any other interested party. 
         [0029]    It should also be mentioned, that such a test phone using SIP could support a broader range of bearer and teleservices, like video and data calls. 
         [0030]    Furthermore, it would be possible to have a single test phone position supporting both native SIP test calls, circuit switched test calls and combinations of SIP and circuit switched test calls. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0031]    By means of the appended figures the invention will now be described in detail: 
           [0032]    In the following 
           [0033]      FIG. 1  shows a typical setup of a test position, 
           [0034]      FIG. 2  shows another typical setup of a test position allowing to monitor an ongoing call involving other parties to access the speech quality, 
           [0035]      FIG. 3  shows a typical setup of a test position in a soft switch architecture, 
           [0036]      FIG. 4  shows a flow chart of messages involved in a test phone using SIP set-up according to the invention, 
           [0037]      FIG. 5   a  shows a first alternative embodiment of the invention, 
           [0038]      FIG. 5   b  shows a second alternative embodiment of the invention, and 
           [0039]      FIG. 5   c  shows a third alternative embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0040]      FIG. 1  shows a typical setup of a test position in an exchange  20 . A fixed test phone  50  is connected via a group switch (not shown) towards the exchange  20 . 
         [0041]      FIG. 2  shows another typical setup of a test position in an exchange  20  allowing for monitoring an ongoing call involving other parties to access the speech quality. 
         [0042]      FIG. 3  shows typical soft switch architecture. Here the exchange is split into a server, responsible for call handling, connecting to one or more media gateways, handling the payload. 
         [0043]    It is only possible to connect a fixed test phone to the soft switch as long the server is equipped with extra hardware supporting the test phone. 
         [0044]    The reason for this is that the server part of a soft switch does normally not handle payload data like voice. 
         [0045]    The media gateway that handles payload data, lack the means to set-up and control test calls in a soft switch network. 
         [0046]      FIG. 4  shows a typical flow of messages involved in a test call. In the following, the content of the messages as well as the name of messages will be shown in italic letters. 
         [0047]    In a set-up, where the Server does not provide for a user-network interface for the test phone, the test phone using SIP first registers with a Registrar for example by the following message
       Register   From : testphone@operator.org   Contact : &lt;195.37.78.173&gt;       
 
         [0051]    The Registrar will typically reply a message
       200 OK.       
 
         [0053]    Once, the test phone is registered or otherwise can communicate to a server via a user-network-interface, the test phone may send an Invite message to a SIP proxy
       Invite   From : testphone@operator.org   To : +496099999   CallID : 12342343@sip.com       which will typically answered by a
       TRYING 100   
       message and possibly one or more Ringing 180 messages.   
 
         [0061]    The Invite message may contain an attribute such as a predefined
       Subject : Test-Call       indicating to the SIP proxy that the call is a test-call.   
 
         [0064]    Furthermore, attributes of the Invite message may contain additional information on the nature of the test call, i.e. which resources to use and/or which information to provide. 
         [0065]    Attributes may be located in the header, e.g. like the subject attribute, and/or in the body of the Invite or any following message. 
         [0066]    In further embodiments such additional information may also be transported via other appropriate methods, such as the SIP INFO method (RFC2976) as shown exemplary in  FIG. 4   b  or the MESSAGE method (RFC3428) as shown exemplary in  FIG. 4   c.    
         [0067]    The SIP proxy in turn will recognize the test-call and once the SIP proxy has received the additional information on the nature of the test call, i.e. which resources to use and/or which information to provide, the SIP proxy instructs the usage of resources and the provisioning of information of the appropriate resources, e.g. within Multimedia-Gateways (M-MGw), via appropriate signaling, e.g. GCP. 
         [0068]    Information provided by the appropriate Multimedia-Gateways (M-MGw) will than in turn be reported to the SIP Proxy again via appropriate signaling, e.g. GCP. 
         [0069]    Than, the Information will be provided via SIP signaling towards the test-phone. For example, the information may be transported via methods, such as the SIP INFO method (RFC2976) or the MESSAGE method (RFC3428). 
         [0070]    In the meantime a corresponding media gateway control function (MGCF) of the SIP proxy/Server may translate some of the data provided in the invite message into corresponding ISUP/BICC signaling. 
         [0071]    This message may contain additional information indicating that the call to be set-up is a test call. Furthermore, other information, e.g. specific resources to be used, may be included as well. 
         [0072]    In further embodiments such information may also be transported via other methods, such as the SIP INFO method (RFC2976) or the MESSAGE method (RFC3428). 
         [0073]    Apparently, the way the information is transported may vary. However, it is preferred to have the information transported according to SIP signaling. 
         [0074]    Such information may be translated by an enhanced media gateway control function (MGCF) into corresponding BICC messages and vice versa. For example, information provided to the test phone may encompass used resources, protocol traces, error codes, dumps, etc . . . . 
         [0075]    Once the called party is reached an OK  200  to the Invite message is sent towards the test phone, which in turn acknowledges the receipt of the message with an ACK message. 
         [0076]    Than, one or more corresponding payload connection(s), e.g. an RTP/UDP connection, is/are established. 
         [0077]    In the meantime, reported Information provided by the appropriate Multimedia-Gateways (M-MGw) will be reported by the SIP Proxy towards the SIP test phone and/or may be stored for further processing. 
         [0078]    Again, such reported Information may be transported towards the SIP test phone by the methods, such as the SIP INFO method (RFC2976) or the MESSAGE method (RFC3428) as described above. 
         [0079]    If information is to be stored, such information can be easily distinguished by means of a unique identifier, such as the Call-Id. Furthermore, the information may include a time stamp. 
         [0080]    Once the test-call is to be finished, either the test phone (not shown) or the called party (as shown) may send a
       BYE message,       which is turn acknowledged by a
       200 OK message.   
       
 
         [0084]    Obviously, also when no connection can be established the resources will report information as instructed backwards to the SIP Proxy. 
         [0085]    Again, such information may be transported by the methods, such as the SIP INFO method (RFC2976) or the MESSAGE method (RFC3428) as described above. 
         [0086]    In order to prevent misuse of the features provided by test-phone functionality as shown above, the procedures may be subject to authorization procedures. 
         [0087]    As a further embodiment, the sip phone may be a soft-phone, i.e. implemented in a computerized device such as a desktop computer, a laptop computer or any comparable device. 
         [0088]    Furthermore, the functionality of an instrument-box as explained above may be implemented in the test-phone either in software or in hardware. 
         [0089]    For example, DTMF tones may be transported via the INFO method. Such DTMF signaling may be used as explained above to transport additional information, i.e. information on the nature of the test call, i.e. which resources to use and/or which information to provide. 
         [0090]    As already indicated it is also possible to let a test phone using SIP instruct an SIP application server. In doing so, it is possible to let automatic test cases being executed by the SIP application servers. 
         [0091]    In doing so, functionality of a test phone using SIP is shifted to the application server. Thereby a simple, standard SIP phone can be used and the specialized processing relating to test calls in a SIP environment is handled by the application server. 
         [0092]    Furthermore, some of the functionality of the Multimedia-Gateways is shifted to the application server as well. The application server is able to handle different types and revisions of MSS nodes without the need to update the MSS nodes. 
         [0093]    Furthermore, this solution also provides for an improved way of authorizing and authentication of users. A SIP application server for example typically has access to confidential parts of the network acting as a filter and firewall. SIP phones can request test calls to the application server. Depending on the user, location, type of test call requested, time of the day, addressed resource, etc. the application server may or may not grant and execute the request after consulting security mechanisms within and outside the SIP domain. 
         [0094]    The application server can be part of a bigger application, securing that a SIP initiated test call is tied to a bigger work flow not available in the SIP domain, like gathering network performance statistics including QoS metrics, as well as scheduling maintenance staff and hardware replacement. 
         [0095]    Such an application server may be instructed after a SIP session is successfully established by sending appropriate SIP-INFO message(s). 
         [0096]    The results from the tests are send back via SIP-INFO messages. 
         [0097]    The test phone will instruct the SIP application server. In this case the test phone using SIP could instruct an SIP application server to perform tests remotely, on request or even in a scheduled way. The results can either be stored and/or provided back to the instructing test phone or any other interested party.