6.2.3: Interoperability

Where ICT with RTT functionality interoperates with other ICT with RTT functionality (as required by 6.2.1.1) they shall support at least one of the four RTT interoperability mechanisms described below:

a) ICT interoperating over the Public Switched Telephone Network (PSTN), with other ICT that directly connects to the PSTN as described in Recommendation ITU-T V.18 [i.23] or any of its annexes for text telephony signals at the PSTN interface;

b) ICT interoperating with other ICT using VOIP with Session Initiation Protocol (SIP) and using real-time text that conforms to RFC 4103 [i.13];

c) ICT interoperating with other ICT using RTT that conforms with the IP Multimedia Sub-System (IMS) set of protocols specified in TS 126 114 [i.10], TS 122 173 [i.11] and TS 134 229 [i.12];

d) ICT interoperating with other ICT using a relevant and applicable common specification for RTT exchange that is published and available. This common specification shall include a method for indicating loss or corruption of characters.

Testing methods

Type of complianceTest
Pre-conditions
    1. The ICT under test supports two-way voice communication.
    2. The ICT under test has RTT functionality.
      Procedure
      1. Check that the ICT interoperates over the Public Switched Telephone Network (PSTN), with other ICT that directly connects to the PSTN as described in Recommendation ITU-T V.18 [i.23] or any of its annexes for text telephony signals at the PSTN interface.
      2. Check that the ICT interoperates with other ICT using VOIP with Session Initiation Protocol (SIP) and using real-time text that conforms to RFC 4103 [i.13].
      3. Check that the ICT interoperates with other ICT using RTT that conforms with the IP Multimedia Sub-System (IMS) set of protocols specified in TS 126 114 [i.10], TS 122 173 [i.11] and TS 134 229 [i.12].
      4. Check that the ICT interoperates with other ICT using a relevant and applicable common specification that is published and available.
      5. Check that the common specification in check 4 includes a method for indicating loss or corruption of characters.
      Result Pass: Check 1 or 2 or 3 or both 4 and 5 are true
      Fail: All of Checks 1, 2, 3 and at least one of 4 or 5 are false

      Requirement details

      Reference number: 6.2.3

      Related requirements

      Related functional statements

      Related technical requirements

      No related technical requirements are associated with this technical requirement