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DSL.Indd 1 IMPOSEBDSL.Indd 14.05.2004, 16:50:34 14.05.2004 ons". Recommendati (DSL) line subscriber digital of "Overview G.995.1, Recommendation also see information, detailed more For pairs". one line networking systems on metallic metallic on systems networking line one ph in-premises and access customer for "Transceivers of area the in Recommendations of development the for responsible is ITU-T subscriber line subscriber Very high speed digital digital speed high Very VDSL subscriber line subscriber Asymmetric digital Asymmetric ADSL/ADSL2/ADSL2+ digital subscriber line subscriber digital Single-pair high-speed Single-pair SHDSL User Network Interface Network User Service Node Interface Node Service UNI/XNI SNI Voice – PSTN – – N-ISDN Services N-ISDN – Data Splitter Splitter Copper Twisted Pair Twisted Copper Subscriber Line Subscriber Audio xTU-C xTU-R – Leased Lines Leased – – IP-Based Services IP-Based – e.g. Video on Demand on Video e.g. Remote end Remote Central Office end Office Central – Video Services, Services, Video – Transceiver Unit, Transceiver Transceiver Unit, Transceiver – B-ISDN Services B-ISDN – Video xTU-R, xTU-C, for DSL transceivers DSL for Handshake procedures procedures Handshake Central Office Central Premises Customer Handshake ITU-T International Telecommunication Union The leader on DSL G.994.1, Handshake procedures for digital subscriber line (DSL) transceivers Standards Provides a flexible mechanism for DSL transceivers to exchange capabilities and to select a common mode of operation. It includes parameters relating to service and SHDSL application requirements as well as parameters pertinent to various DSL transceivers. G.991.2, Single-pair high-speed digital subscriber line (SHDSL) transceivers Related Recommendations Duplex operation over one copper pair. Optional multi-pair operation for extended reach or higher net data rates. G.991.1 – High bit rate digital subscriber line (HDSL) Net data rate of 192 kbit/s to 2.312 Mbit/s. Optional transceivers extensions allow net data rates up to 5.696 Mbit/s. G.995.1 – Overview of digital subscriber line (DSL) Line code: Trellis Coded Pulse Amplitude Modulation Recommendations (TC-PAM). G.996.1 – Test procedures for digital subscriber line (DSL) transceivers ADSL G.997.1 – Physical layer management for digital subscri- ber line (DSL) transceivers G.992.1, Asymmetric digital subscriber line (ADSL) G.989.x – Phoneline networking transceivers transceivers One copper pair. Net data rate ranging up to a minimum of 6 Mbit/s downstream and 640 kbit/s upstream. Optional Digital Subscriber Line support of higher net data rates. Line code: Discrete MultiTone (DMT). means G.992.3, Asymmetric digital subscriber line transceivers 2 (ADSL2) One copper pair. Net data rate ranging up to a minimum of · Support for wide range of services 8 Mbit/s downstream and 800 kbit/s upstream. Optional · IP-based services support of higher net data rates. · Audio/video services Line code: Discrete MultiTone (DMT). · ATM-based services · Frame relay services G.992.5, Asymmetric Digital Subscriber Line (ADSL) · N-ISDN and B-ISDN transceivers – Extended bandwidth ADSL2 · 64 kbit/s-based voice and data services (ADSL2+) One copper pair. Net data rate ranging up to a minimum of · Exploiting existing infrastructure 16 Mbit/s downstream and 800 kbit/s upstream. Optio- Provides cost-effective transport of high-speed digi- nal support of higher net data rates. tal signals over existing copper wire infrastructure Line code: Discrete MultiTone (DMT). · Advanced technology VDSL Modulation techniques such as: · DMT (Discrete MultiTone) · QAM (Quadrature Amplitude Modulation) G.993.1, Very high speed digital subscriber line founda- · TC-PAM (Trellis Coded Pulse Amplitude tion Modulation) One copper pair. Permits the transmission of asymme- · Handshake procedures tric and symmetric aggregate data rates up to tens of Mbit/s on twisted pairs. It includes worldwide frequency plans that allow asymmetric and symmetric services in Your the same group of twisted pairs. Line code: Discrete MultiTone (DMT) or, alternatively, fast access Quadrature Amplitude Modulation (QAM). to today’s and For more information on ongoing GPON Recommen- dation activities, please check the ITU-T Study Groups future services website at: http://www.itu.int/ITU-T 05.2004 [email protected] IMPOSEBDSL.indd 1 14.05.2004, 16:50:34 ons". Recommendati (DSL) line subscriber digital of "Overview G.995.1, Recommendation also see information, detailed more For pairs". one line networking systems on metallic metallic on systems networking line one ph in-premises and access customer for "Transceivers of area the in Recommendations of development the for responsible is ITU-T subscriber line subscriber Very high speed digital digital speed high Very VDSL subscriber line subscriber Asymmetric digital Asymmetric ADSL/ADSL2/ADSL2+ digital subscriber line subscriber digital Single-pair high-speed Single-pair SHDSL User Network Interface Network User Service Node Interface Node Service UNI/XNI SNI Voice – PSTN – – N-ISDN Services N-ISDN – Data Splitter Splitter Copper Twisted Pair Twisted Copper Subscriber Line Subscriber Audio xTU-C xTU-R – Leased Lines Leased – – IP-Based Services IP-Based – e.g. Video on Demand on Video e.g. Remote end Remote Central Office end Office Central – Video Services, Services, Video – Transceiver Unit, Transceiver Transceiver Unit, Transceiver – B-ISDN Services B-ISDN – Video xTU-R, xTU-C, for DSL transceivers DSL for Handshake procedures procedures Handshake Central Office Central Premises Customer Handshake ITU-T International Telecommunication Union The leader on DSL G.994.1, Handshake procedures for digital subscriber line (DSL) transceivers Standards Provides a flexible mechanism for DSL transceivers to exchange capabilities and to select a common mode of operation. It includes parameters relating to service and SHDSL application requirements as well as parameters pertinent to various DSL transceivers. G.991.2, Single-pair high-speed digital subscriber line (SHDSL) transceivers Related Recommendations Duplex operation over one copper pair. Optional multi-pair operation for extended reach or higher net data rates. G.991.1 – High bit rate digital subscriber line (HDSL) Net data rate of 192 kbit/s to 2.312 Mbit/s. Optional transceivers extensions allow net data rates up to 5.696 Mbit/s. G.995.1 – Overview of digital subscriber line (DSL) Line code: Trellis Coded Pulse Amplitude Modulation Recommendations (TC-PAM). G.996.1 – Test procedures for digital subscriber line (DSL) transceivers ADSL G.997.1 – Physical layer management for digital subscri- ber line (DSL) transceivers G.992.1, Asymmetric digital subscriber line (ADSL) G.989.x – Phoneline networking transceivers transceivers One copper pair. Net data rate ranging up to a minimum of 6 Mbit/s downstream and 640 kbit/s upstream. Optional Digital Subscriber Line support of higher net data rates. Line code: Discrete MultiTone (DMT). means G.992.3, Asymmetric digital subscriber line transceivers 2 (ADSL2) One copper pair. Net data rate ranging up to a minimum of · Support for wide range of services 8 Mbit/s downstream and 800 kbit/s upstream. Optional · IP-based services support of higher net data rates. · Audio/video services Line code: Discrete MultiTone (DMT). · ATM-based services · Frame relay services G.992.5, Asymmetric Digital Subscriber Line (ADSL) · N-ISDN and B-ISDN transceivers – Extended bandwidth ADSL2 · 64 kbit/s-based voice and data services (ADSL2+) One copper pair. Net data rate ranging up to a minimum of · Exploiting existing infrastructure 16 Mbit/s downstream and 800 kbit/s upstream. Optio- Provides cost-effective transport of high-speed digi- nal support of higher net data rates. tal signals over existing copper wire infrastructure Line code: Discrete MultiTone (DMT). · Advanced technology VDSL Modulation techniques such as: · DMT (Discrete MultiTone) · QAM (Quadrature Amplitude Modulation) G.993.1, Very high speed digital subscriber line founda- · TC-PAM (Trellis Coded Pulse Amplitude tion Modulation) One copper pair. Permits the transmission of asymme- · Handshake procedures tric and symmetric aggregate data rates up to tens of Mbit/s on twisted pairs. It includes worldwide frequency plans that allow asymmetric and symmetric services in Your the same group of twisted pairs. Line code: Discrete MultiTone (DMT) or, alternatively, fast access Quadrature Amplitude Modulation (QAM). to today’s and For more information on ongoing GPON Recommen- dation activities, please check the ITU-T Study Groups future services website at: http://www.itu.int/ITU-T 05.2004 [email protected] IMPOSEBDSL.indd 1 14.05.2004, 16:50:34.
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