Examples of Communication Systems/General Description of DSL - Revision history

Maintenance script: Add German interlanguage link

2026-03-16T12:26:06Z

Add German interlanguage link

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	{{Display}}		{{Display}}
			[[de:Beispiele_von_Nachrichtensystemen/Allgemeine_Beschreibung_von_DSL]]

Guenter at 21:01, 21 March 2023

2023-03-21T21:01:01Z

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	'''~~Non~~ part of the xDSL standard:~~''' '''KORREKTUR: not part?~~'''		'''Not part of the xDSL standard:'''
	#There are also many products circulating under  "DSL"  that are not part of the xDSL standard.		#There are also many products circulating under  "DSL"  that are not part of the xDSL standard.
	#They are often only intended to make it clear that fast data access is involved.		#They are often only intended to make it clear that fast data access is involved.

Hwang at 18:45, 21 March 2023

2023-03-21T18:45:04Z

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	These efforts culminated in April 1998 in the publication of the ETSI Technical Specification  "$\text{TS 101 270-1}$",  which defines as modulation methods both  [[Modulation_Methods/Further_OFDM_Applications#A_brief_description_of_DSL_-_Digital_Subscriber_Line\|$\rm DMT$]]  $($"Discrete Multitone Transmission"$)$  and  [[Modulation_Methods/Quadrature_Amplitude_Modulation\|$\rm QAM$]]  $($"Quadrature Amplitude Modulation"$)$.  The semiconductor manufacturers could not agree on a worldwide line code standard for a long time and there was even talk of the  "VDSL Line Code War".		These efforts culminated in April 1998 in the publication of the ETSI Technical Specification  "$\text{TS 101 270-1}$",  which defines as modulation methods both  [[Modulation_Methods/Further_OFDM_Applications#A_brief_description_of_DSL_-_Digital_Subscriber_Line\|$\rm DMT$]]  $($"Discrete Multitone Transmission"$)$  and  [[Modulation_Methods/Quadrature_Amplitude_Modulation\|$\rm QAM$]]  $($"Quadrature Amplitude Modulation"$)$.  The semiconductor manufacturers could not agree on a worldwide line code standard for a long time and there was even talk of the  "VDSL Line Code War".

	In 2003,  at the so-called  "VDSL Olympics",  the decision was made in favor of DMT and against QAM or the slightly modified variant  [[Examples_of_Communication_Systems/xDSL_as_Transmission_Technology#~~Carrierless_Amplitude_Phase_Modulation_.28CAP.29~~\|$\rm CAP$]]  $($"Carrierless Amplitude Phase Modulation"$)$,  namely		In 2003,  at the so-called  "VDSL Olympics",  the decision was made in favor of DMT and against QAM or the slightly modified variant  [[Examples_of_Communication_Systems/xDSL_as_Transmission_Technology#Carrierless_Amplitude_Phase_Modulation\|$\rm CAP$]]  $($"Carrierless Amplitude Phase Modulation"$)$,  namely
	*because of the robustness of DMT against narrowband interference sources,		*because of the robustness of DMT against narrowband interference sources,

Hwang at 18:38, 21 March 2023

2023-03-21T18:38:03Z

← Older revision		Revision as of 20:38, 21 March 2023
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	'''Non part of the xDSL standard:'''		'''Non part of the xDSL standard:''' '''KORREKTUR: not part?'''
	#There are also many products circulating under  "DSL"  that are not part of the xDSL standard.		#There are also many products circulating under  "DSL"  that are not part of the xDSL standard.
	#They are often only intended to make it clear that fast data access is involved.		#They are often only intended to make it clear that fast data access is involved.

Guenter at 16:39, 14 March 2023

2023-03-14T16:39:20Z

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	The graph illustrates the relationships between		The graph illustrates the relationships between milestones in the theoretical and practical design of transmission systems.
	#milestones in the theoretical and practical design of transmission systems,
	~~#parallel advances in semiconductor development,  and the~~
	~~#realization of the individual xDSL standards with corresponding data rates~~.



	[[File:~~EN_Bei_2_1_s3_v3~~.png\|right\|frame\|Milestones of the industrial xDSL development]]		[[File:EN_Bei_2_1_s3_v4.png\|right\|frame\|Milestones of the industrial xDSL development]]
	$\text{Milestones of DSL development in short form:}$		$\text{Milestones of DSL development in short form:}$

Guenter at 15:53, 8 March 2023

2023-03-08T15:53:50Z

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	These efforts culminated in April 1998 in the publication of the ETSI Technical Specification  "$\text{TS 101 270-1}$",  which defines as modulation methods both  [[Modulation_Methods/Further_OFDM_Applications#A_brief_description_of_DSL_-_Digital_Subscriber_Line\|$\rm DMT$]]  $($"Discrete Multitone Transmission"$)$  and  [[Modulation_Methods/Quadrature_Amplitude_Modulation\|$\rm QAM$]]  $($Quadrature Amplitude Modulation$)$.  The semiconductor manufacturers could not agree on a worldwide line code standard for a long time and there was even talk of the  "VDSL Line Code War".		These efforts culminated in April 1998 in the publication of the ETSI Technical Specification  "$\text{TS 101 270-1}$",  which defines as modulation methods both  [[Modulation_Methods/Further_OFDM_Applications#A_brief_description_of_DSL_-_Digital_Subscriber_Line\|$\rm DMT$]]  $($"Discrete Multitone Transmission"$)$  and  [[Modulation_Methods/Quadrature_Amplitude_Modulation\|$\rm QAM$]]  $($"Quadrature Amplitude Modulation"$)$.  The semiconductor manufacturers could not agree on a worldwide line code standard for a long time and there was even talk of the  "VDSL Line Code War".

	In 2003,  at the so-called  "VDSL Olympics",  the decision was made in favor of DMT and against QAM or the slightly modified variant  [[Examples_of_Communication_Systems/xDSL_as_Transmission_Technology#Carrierless_Amplitude_Phase_Modulation_.28CAP.29\|$\rm CAP$]]  $($"Carrierless Amplitude Phase Modulation"$)$,  namely		In 2003,  at the so-called  "VDSL Olympics",  the decision was made in favor of DMT and against QAM or the slightly modified variant  [[Examples_of_Communication_Systems/xDSL_as_Transmission_Technology#Carrierless_Amplitude_Phase_Modulation_.28CAP.29\|$\rm CAP$]]  $($"Carrierless Amplitude Phase Modulation"$)$,  namely
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	==Exercises for the chapter ==		==Exercises for the chapter ==
	<br>		<br>
	[[Exercise_2.1:_General_Description_of_xDSL\|"Exercise 2.1: General Description of xDSL"]]		[[Exercise_2.1:_General_Description_of_xDSL\|Exercise 2.1: General Description of xDSL]]



	{{Display}}		{{Display}}

Guenter at 15:50, 8 March 2023

2023-03-08T15:50:39Z

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	== Development of ADSL and VDSL in Europe ==		== Development of ADSL and VDSL in Europe ==
	<br>		<br>
	From the above compilation it can be seen that the  '''ADSL standardization'''  was predominantly driven by  [https://en.wikipedia.org/wiki/American_National_Standards_Institute "ANSI"]  (''American National Standards Institute'') and that ~~the~~ [https://en.wikipedia.org/wiki/ETSI "ETSI"] (''European Telecommunications Standards Institute'') followed shortly thereafter in each case:		From the above compilation it can be seen that the  »'''ADSL standardization'''«  was predominantly driven by  [https://en.wikipedia.org/wiki/American_National_Standards_Institute $\rm ANSI$]  $($"American National Standards Institute"$)$  and that  [https://en.wikipedia.org/wiki/ETSI $\rm ETSI$]  $($"European Telecommunications Standards Institute"$)$  followed shortly thereafter in each case:
	*The first ADSL standard  ~~('''~~ANSI T1.413~~''')~~  from 1995 was predominantly optimized for video-on-demand services, which is also made clear by the ratio of the downstream and upstream data rates defined herein:  1.5 Mbit/s and 16 kbit/s, 3 Mbit/s and 16 kbit/s, and finally 6 Mbit/s and 64 kbit/s.		#The first ADSL standard   "$\text{ANSI T1.413}$"   from 1995 was predominantly optimized for video-on-demand services,  which is also made clear by the ratio of the downstream and upstream data rates defined herein:  $1.5$  Mbit/s and  $16$  kbit/s,  $3$  Mbit/s and  $16$  kbit/s, and finally  $6$  Mbit/s and  $64$ kbit/s.
	*The frequency range was originally defined in such a way that ADSL could only be used to operate an analog telephone on the access line. ETSI published a technical report ~~in 1996~~  ~~('''~~ETR 328~~''')~~  with only a few detailed changes and the possibility to transmit 2048 kbit/s.		#The frequency range was originally defined in such a way that ADSL could only be used to operate an analog telephone on the access line.  ETSI published a technical report   "$\text{ETR 328}$"   in 1996 with only a few detailed changes and the possibility to transmit  $2048$  kbit/s.
	*Since the second version of the ANSI standard also allowed only one additional analog telephone, ETSI then defined an ADSL system that differed both in bit rates and in the possibility of using an ISDN basic access on the same twisted pair.		#Since the second version of the ANSI standard also allowed only one additional analog telephone,  ETSI then defined an ADSL system that differed both in bit rates and in the possibility of using an ISDN basic access on the same twisted pair.
	*The ANSI and ETSI standardization efforts of the previous years resulted in the  [https://en.wikipedia.org/wiki/International_Telecommunication_Union "ITU"] recommendation ~~'''~~G.992.1~~'''~~ in 1999, which includes both standards and thus allows many options for implementation.		#The ANSI and ETSI standardization efforts of the previous years resulted in the  [https://en.wikipedia.org/wiki/International_Telecommunication_Union "ITU"] recommendation  "$\text{G.992.1}$"   in 1999,  which includes both standards and thus allows many options for the implementation.


	However, the many options led to major conceptual differences at the end of the 1990s - worldwide, within Europe and also nationally, depending on the semiconductor manufacturer, among other things. Only a few systems, modems and measuring devices interoperated with other manufacturers.		However,  the many options led to major conceptual differences at the end of the 1990s  –  worldwide,  within Europe and also nationally  –  depending on the semiconductor manufacturer,  among other things.  Only a few systems,  modems,  and measuring devices interoperated with other manufacturers.

	To counteract this proliferation, Deutsche Telekom AG passed the ~~Technical Guideline~~  ~~'''~~1TR112~~'''~~ at the end of 2001, defining all the necessary interface parameters to ensure the interoperability of different manufacturer modems on the provider and customer side. Due to Telekom's market power, this became the quasi-standard for Germany.		To counteract this proliferation,  The  "Deutsche Telekom AG"  passed the technical guideline  "$\text{1TR112}$"   at the end of 2001,  defining all the necessary interface parameters to ensure the interoperability of different manufacturer modems on the provider and customer side.
	Furthermore, only those ADSL variants were used in Germany that allowed simultaneous operation of ISDN at any time. Thus, when switching from POTS to ISDN, it was not necessary to change the ADSL version as well.		*Due to Telekom's market power,  this became the quasi-standard for Germany.

			*Furthermore,  only those ADSL variants were used in Germany that allowed simultaneous operation of ISDN at any time.  Thus,  when switching from POTS to ISDN,  it was not necessary to change the ADSL version as well.

	The '''VDSL standardization''' relevant for Europe was decisively shaped by ETSI and often happened in parallel to the American activities. Overall, VDSL standardization proceeded in a more orderly fashion than ADSL. The 3-step plan adopted by ETSI provided for:
			The  »'''VDSL standardization'''«  relevant for Europe was decisively shaped by ETSI and often happened in parallel to the American activities.  Overall,  VDSL standardization proceeded in a more orderly fashion than ADSL.  The 3-step plan adopted by ETSI provided for:
	*Stage 1:  Functional and electrical requirements for VDSL systems,		*Stage 1:  Functional and electrical requirements for VDSL systems,

	*Stage 2:  Transmission coding and access method requirements,		*Stage 2:  Transmission coding and access method requirements,

	*Stage 3:  Interoperability requirements.		*Stage 3:  Interoperability requirements.


	These efforts culminated in April 1998 in the publication of the ETSI Technical Specification  ~~'''~~TS 101 270-1~~'''~~, which defines as modulation methods both  [[Modulation_Methods/Further_OFDM_Applications#A_brief_description_of_DSL_-_Digital_Subscriber_Line\|"DMT"]]  (''Discrete Multitone Transmission'') and  [[Modulation_Methods/Quadrature_Amplitude_Modulation\|"QAM"]]  (~~quadrature amplitude modulation~~). The semiconductor manufacturers could not agree on a worldwide line code standard for a long time and there was even talk of the ''VDSL Line Code War''. In 2003, at the so-called ''VDSL Olympics'', the decision was made in favor of DMT and against QAM or the slightly modified variant  [[Examples_of_Communication_Systems/xDSL_as_Transmission_Technology#Carrierless_Amplitude_Phase_Modulation_.28CAP.29\|"CAP"]]  (''Carrierless Amplitude Phase Modulation''), namely.		These efforts culminated in April 1998 in the publication of the ETSI Technical Specification  "$\text{TS 101 270-1}$",  which defines as modulation methods both  [[Modulation_Methods/Further_OFDM_Applications#A_brief_description_of_DSL_-_Digital_Subscriber_Line\|$\rm DMT$]]  $($"Discrete Multitone Transmission"$)$  and  [[Modulation_Methods/Quadrature_Amplitude_Modulation\|$\rm QAM$]]  $($Quadrature Amplitude Modulation$)$.  The semiconductor manufacturers could not agree on a worldwide line code standard for a long time and there was even talk of the  "VDSL Line Code War".

			In 2003,  at the so-called  "VDSL Olympics",  the decision was made in favor of DMT and against QAM or the slightly modified variant  [[Examples_of_Communication_Systems/xDSL_as_Transmission_Technology#Carrierless_Amplitude_Phase_Modulation_.28CAP.29\|$\rm CAP$]]  $($"Carrierless Amplitude Phase Modulation"$)$,  namely
	*because of the robustness of DMT against narrowband interference sources,		*because of the robustness of DMT against narrowband interference sources,
	*although QAM (CAP) would allow faster call setup.
			*although QAM/ CAP would allow a faster call setup.

Guenter at 14:56, 7 March 2023

2023-03-07T14:56:29Z

Show changes

Guenter at 10:24, 7 March 2023

2023-03-07T10:24:04Z

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	*$\text{WDSL}$  –  "Wireless Digital Subscriber Line":  Brand name of a German company that uses wireless technology to enable data rates of up to  $108$  Mbit/s in DSL-free areas.		*$\text{WDSL}$  –  "Wireless Digital Subscriber Line":  Brand name of a German company that uses wireless technology to enable data rates of up to  $108$  Mbit/s in DSL-free areas.

	*$\text{mvoxSatellit}$:   Brand name of an Internet access with  "WiMAX-like radio technology",  which~~, ~~ like WDSL and PortableDSL~~, ~~ is only an auxiliary construct for DSL-free areas.		*$\text{mvoxSatellit}$:   Brand name of an Internet access with  "WiMAX-like radio technology",  which like WDSL and PortableDSL is only an auxiliary construct for DSL-free areas.


	==Historical development of xDSL - standardizations ==		==Historical development of xDSL standardizations ==
	<br>		<br>

			[[File:EN_Bei_2_1_s3_v3.png\|right\|frame\|Industrial xDSL development]]

	The need for digital subscriber lines to improve line utilization and increase customer convenience was recognized as early as the 1970s. After the ISDN specification in the early 1980s, the actual development of DSL began.		The need for digital subscriber lines to improve line utilization and increase customer convenience was recognized as early as the 1970s. After the ISDN specification in the early 1980s, the actual development of DSL began.

	*This development was influenced by the findings of many groups located around the world. Accordingly, standardization proceeded in an unstructured manner. From the list below ("Milestones"), it is clear that different committees around the world were in charge of the various standards.		*This development was influenced by the findings of many groups located around the world. Accordingly, standardization proceeded in an unstructured manner. From the list below ("Milestones"), it is clear that different committees around the world were in charge of the various standards.
	*In the industry, the technical realizations of the individual xDSL standards often deviated noticeably from the specification. For example, some standards were started as projects even before the specification, since the industry parties were also represented in the standardization committees.		*In the industry, the technical realizations of the individual xDSL standards often deviated noticeably from the specification. For example, some standards were started as projects even before the specification, since the industry parties were also represented in the standardization committees.


	~~[[File:EN_Bei_2_1_s3_v3.png\|right\|frame\|Industrial xDSL development]]~~
	The graphic illustrates relationships between.		The graphic illustrates relationships between.
	*milestones in the theoretical and practical design of transmission systems,		*milestones in the theoretical and practical design of transmission systems,
	*parallel advances in semiconductor development, and the		*parallel advances in semiconductor development, and the
	*realization of the individual xDSL standards with the corresponding data rates.		*realization of the individual xDSL standards with the corresponding data rates.
	~~<br clear=all>~~

	Here are thenbsp; '''Milestones'''nbsp; of DSL development in short form:		Here are thenbsp; '''Milestones'''nbsp; of DSL development in short form:
	*'''1986'''   A first concept for HDSL ('''''H'''igh-bit-rate '''D'''igital '''S'''ubscriber '''L'''ine'') is defined by AT&T, Bell Laboratories and Bellcore.
	*'''1989'''   First HDSL prototypes appear. # Bellcore meanwhile works on the conceptual definition of ADSL.		'''1986'''   A first concept for HDSL ('''''H'''igh-bit-rate '''D'''igital '''S'''ubscriber '''L'''ine'') is defined by AT&T, Bell Laboratories and Bellcore.

			'''1989'''   First HDSL prototypes appear. # Bellcore meanwhile works on the conceptual definition of ADSL.
	*'''1992'''   In February, first publication of '''ANSI Technical Report E1T1/92-002R1''': "''High Bit-rate Digital Subscriber Line'' - HDSL". # The first prototypes for ADSL ('''''A'''symmetric '''D'''igital '''S'''ubscriber '''L'''ine'') appear.		*'''1992'''   In February, first publication of '''ANSI Technical Report E1T1/92-002R1''': "''High Bit-rate Digital Subscriber Line'' - HDSL". # The first prototypes for ADSL ('''''A'''symmetric '''D'''igital '''S'''ubscriber '''L'''ine'') appear.
	*'''1994'''   The VDSL concept ('''''V'''ery-high-speed '''D'''igital '''S'''ubscriber '''L'''ine'') is discussed for the first time.		*'''1994'''   The VDSL concept ('''''V'''ery-high-speed '''D'''igital '''S'''ubscriber '''L'''ine'') is discussed for the first time.

Guenter at 16:55, 6 March 2023

2023-03-06T16:55:01Z

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	[[File:~~EN_Bei_2_1_s3_v2~~.png\|right\|frame\|Industrial xDSL development]]		[[File:EN_Bei_2_1_s3_v3.png\|right\|frame\|Industrial xDSL development]]
	The graphic illustrates relationships between.		The graphic illustrates relationships between.
	*milestones in the theoretical and practical design of transmission systems,		*milestones in the theoretical and practical design of transmission systems,