|(Continuation of Questions 15/16 and 18/16) |
This Question deals with the implementation and interaction aspects of signal processing network equipment/terminals for transporting voice and voiceband traffic in networks.
With the increased popularity of packet-based networks using Internet Protocol (IP), more and more speech traffic is expected to be carried over these transport networks. Therefore, it will also be observed a significant amount of voice and voiceband data traffic going through signal processing network equipment (SPNE), such as gateway and circuit multiplication equipment that interconnect the GSTN and packet networks as well as interconnect different packet networks. For this reason, there is a need to ensure a high quality of service for voice and voiceband data carried in part or wholly via IP networks.
One of the purposes of this Question is to apply the following aspects in a new generation of voice gateway functions in SPNE (e.g. GSTN to IP gateway, vehicle gateway and integrated access devices) reflecting the experiences gained from previous generations of equipment:
- enhancement of signal compression and processing (including channel multiplexing) techniques to accommodate new types of signals and services;
- enhancement of system controls to maintain end-to-end signal qualities as high as possible.
Another purpose of this Question is to encompass these Recommendations under various equipment specifications and to include performance requirements and test methodologies that will help ensure that the correct and appropriate functionality is present in the equipment. It is not intended to define new protocols, but eventually new requirements for these protocols.
Recommendations have been developed covering circuit multiplication, speech enhancement (network echo cancellers, voice enhancement devices, and automatic level control), and GSTN/IP gateway equipment. In order to minimize the undesirable effects when the SPNEs are connected together, the Question also deals with:
- the logic and protocol requirements needed for the control and coordination of signal processing functionalities in the networks and terminals;
- the study of interaction of SPNE, between different SPNE/terminals, between SPNE and terminals, and between SPNE/terminals and transmission systems;
- the consistency of Recommendations in the area of SPNE.
The Question will attempt to work electronically where possible and to make full use of e-mail and conferencing facilities in an attempt to reduce its carbon footprint.
Study items to be considered include, but are not limited to
- impact of speech processing issues (e.g. speech coding, voice enhancement) related to SPNE on overall network performance;
- specification and Recommendation of functionality, interfaces, performance requirements and functional tests to provide good network performance for transport network equipment for interconnecting various type of networks;
- identify protocols and Internet interworking functions needed to be supported;
- support of functionality needed to ensure minimal end-to-end delay;
- impact of evolving terminal equipment (such as text telephones, modems, facsimile and wireless terminals) on voice quality for terminal equipment and multimedia terminals including home gateways;
- optimization of voice gateway functionality for ATM and IP networks transporting voice and voiceband data traffic;
- interactions between similar and different SPNE/terminals;
- interactions between voiceband signals and SPNE;
- interactions between SPNE and end-terminal equipment;
- interactions between SPNE and transmission systems;
- techniques to ensure high-quality SPNE and terminals Recommendations;
- enhancement of existing or development of new Recommendations to ensure that these interactions do not impair service;
- logic and protocol requirements needed for control and coordination of signal processing functionalities in the networks and terminals. Such logic may be used to get the optimal arrangements of signal processing functionalities in the networks and terminals in a connection, or to configure their parameters for optimum performance;
- the availability of general evaluation procedures;
- interaction between similar and different SPNE/terminals;
- interaction between SPNE and other voiceband traffic technologies, including text telephony;
- the interaction of acoustic echo control devices with SPNE/terminals;
- interaction between SPNE/terminals and transport systems;
- interaction between SPNE/terminals in networks that include satellite links;
- the effect of tandem signal processing avoidance and methods of minimizing the impact of these effects (e.g. codec bypass or tandem-free operation) on in-path SPNE/terminals;
- the methodology and technique to minimize the undesirable interactions among SPNEs and SPNEs with terminals to achieve better voice quality (e.g. dynamic coordination of signal processing functions);
- study for SPNE/terminals used in next generation networks (SPNE/terminals interworking between GSTN and packet/IP networks);
- evaluation of the corresponding ITU T Recommendations;
- to ensure the interoperability between SPNE, e.g. dynamic coordination, data relay
- to consider any additions to Recommendations that may help to measure and reduce the impact of climate change. Examples include reduced power consumption of hardware and hardware tools, and reduced complexity of algorithms.
Tasks include, but are not limited to:
- improving voice performance for various gateways including vehicle and home gateways (e.g. implementation of tandem avoidance mechanisms of speech processing functions);
- guidelines to perform tests for measuring performance of signal processing functionalities (e.g. embedded echo cancellers) of a gateway equipment;
- coordination of activities verifying the consistency of SPNE/terminal Recommendations;
- develop guidelines on the preferred locations of SPNE in networks;
- addressing performance issues between SPNE/terminals and other voiceband traffic types including text telephony;
- develop draft new Recommendation(s) on control logic for SPNE and between SPNE and terminals; on mechanism for dynamic and soft coordination of SPNE/terminals to achieve optimal end-to-end voice quality; and on provision of information and requirements for SPNE;
- maintain and further develop ITU T G.161, Q.115-series, G.799.2 and G.776.1;
- enhancement of ITU-T G.799.1/Y.1451.1 to include support of ATM networks for GSTN interface;
- revision of ITU-T G.799.3 (IP-to-IP Gateway) that can be used for the bulk interconnection of voice and voiceband data traffic of two network operators;
- aintenance of ITU T G.763, G.764, G.765, G.766, G.767, G.768, G.769/Y.1242, G.799.1/Y.1451.1, G.799.3 and I.733.
An up-to-date status of work under this Question is found in the SG 16 work programme (http://itu.int/ITU-T/workprog/wp_search.aspx?sp=15&q=18/16).
- ITU-T G.108.2, G.114, G.131, G.136, G.160-series, G.173, G.175, G.177, G.710- and G.720-series, G.760-series, G.827, G.828, P.330, P.340, P.342, P.1010, P.1100, P.1110, P.501, P.502, P.82, P.84, P.800, P.831, P.835, P.840, P.862-series, Q.50-series, Q.55, Q.56, Q.115-series, S.1522, T.30, T.38, V.18, V.20-series, V.32, V.34, V.150.x-series, V.151, V.152
- 1/16 and 21/16 on multimedia systems, terminals, protocols and architectures
- 3/16 and on media gateway control
- 7/16 and 10/16 on speech coding algorithms
- 15/16 on voiceband signal compression protocols
- 16/16 on network/terminals signal processing
- 27/16 on vehicle gateway platform
- Study groups
- ITU-T SG 2 on operational aspects of networks and performance and network management
- ITU-T SG 11 on signalling requirements and protocols
- ITU-T SG 12 on speech performance
- ITU-T SG 13 on IP-based networks, NGN, FN and Internetworking
- ITU-T SG 15 on core network architecture, and management and control of transport systems and equipment
- ITU-R SGs 4 and 5 on voice on mixed terrestrial/satellite networks
- Other bodies
- Broadband Forum on ATM, MPLS and frame relay transport
- ETSI TISPAN, 3GPP, 3GPP TSG SA4, 3GPP2 and TIA on mobile networks, mobile network architectures, tandem-free operation and the logic and protocol requirements needed for the control and coordination of signal processing functionalities in the networks and terminals
- IETF on IP transport, applications, speech service control, and operation and management
- ISO, IEC