Difference between revisions of "Exercise 2.2Z: DSL Internet Connection"

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{{quiz-Header|Buchseite=Beispiele von Nachrichtensystemen/xDSL–Systeme
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{{quiz-Header|Buchseite=Examples_of_Communication_Systems/xDSL_Systems
 
}}
 
}}
  
[[File:|right|frame|]]
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[[File:EN_Bei_Z_2_2.png|right|frame|Standard DSL configuration]]
  
 +
The graphic shows a possible configuration of a DSL Internet connection,
 +
*above the subscriber side and
 +
*below the components of the exchange,
  
  
 +
which forwards the telephone signals (analog or ISDN) via the digital exchange (DIV) to the telephone network and the data signals to the Internet.
  
 +
The components on the customer side, viz.
  
 +
*Splitter,
 +
*NTBA,
 +
*DSL router/modem
  
  
===Fragebogen===
+
are the focus of the following questions.
 +
 
 +
 
 +
 
 +
 
 +
 
 +
 
 +
Hints:
 +
 
 +
*This exercise belongs to the chapter  [[Examples_of_Communication_Systems/xDSL_Systems|"xDSL Systems"]]
 +
 
 +
 
 +
 
 +
 
 +
 
 +
 
 +
 
 +
===Questions===
 
<quiz display=simple>
 
<quiz display=simple>
  
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{ Which components separate voice and data signal at the subscriber?
 +
|type="[]"}
 +
- DSL router/modem,
 +
- DSLAM,
 +
+ splitter.
 +
 +
 +
{ What is the importance and task of the NTBA?
 +
|type="[]"}
 +
+ The NTBA is only required for ISDN.
 +
+ Conversion of&nbsp; $\rm U_{\rm KO}$&nbsp; to&nbsp; $\rm S_0$&nbsp; (two-wire &nbsp; &rArr; &nbsp; four-wire).
 +
+ ISDN code conversion from "MMS43" to AMI code.
  
 +
{ What are the tasks of the DSL modem or router?
 +
|type="[]"}
 +
+ These units accomplish a protocol conversion.
 +
+ These units contain the "xTU-R" plug-in module.
 +
- These units contain the "xTU-C" plug-in module.
  
  
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</quiz>
 
</quiz>
  
===Musterlösung===
+
===Solution===
 
{{ML-Kopf}}
 
{{ML-Kopf}}
'''(1)'''&nbsp; Richtig ist <u>der Lösungsvorschlag 3</u>. Der Splitter ist eine Kombination aus Hoch– und Tiefpass, der die Trennung des Telefonsignals (unterhalb von $120 \ \rm kHz$) vom DSL–Datensignal (oberhalb von $138 \ \rm kHz$) übernimmt bzw. deren Kombination.
+
'''(1)'''&nbsp; Correct is <u>the proposed solution 3</u>:
 +
*The splitter is a combination of a high-pass and low-pass filter that handles the separation of the telephone signal (below 120 kHz) from the DSL data signal (above 138 kHz), or their combination.
 +
 
  
'''(2)'''&nbsp; <u>Alle Aussagen</u> sind richtig. Genauere Informationen zum ISDN–Basisanschluss und insbesondere zum Netzabschluss (NTBA) finden Sie im Kapitel [[Beispiele_von_Nachrichtensystemen/ISDN-Basisanschluss|ISDN-Basisanschluss]] dieses Buches.
+
'''(2)'''&nbsp; <u>All statements</u> are correct.
 +
*For more detailed information on the ISDN basic access and especially on the network termination (NTBA), please refer to the chapter [[Examples_of_Communication_Systems/ISDN_Basic_Access|"ISDN Basic Access"]] of this book.
  
'''(3)'''&nbsp; Richtig sind <u>die beiden ersten Lösungsvorschläge</u>. Bei den heutigen DSL–Systemen dient stets ATM (''Asynchronous Transfer Mode'') als Basisprotokoll. Die Endgeräte der Kunden verwenden meist das Ethernet–Protokoll und können ATM–Zellen nicht verarbeiten. Die Protokollumsetzung geschieht anhand des Protokolls AAL5 (ATM ''Adaption Layer Protocol 5'').
 
  
Die teilnehmerseitige xDSL–Einheit ist xTU–R (xDSL ''Transceive Unit Remote'') und befindet sich als Einschub im xDSL–Modem bzw. im Router. Dagegen ist das xTU–C (xDSL ''Transceive Unit Central Office'') im DSLAM (''Digital Subscriber Line Access Multiplexer'') in der Vermittlungsstelle oder im Kabelverzweiger untergebracht, also auf der Netzbetreiberseite.
+
'''(3)'''&nbsp; Correct are the <u>suggested solutions 1 and 2</u>:
 +
*DSL systems always use ATM (''Asynchronous Transfer Mode'') as the basic protocol.
 +
*The customers' terminal equipment, however, usually uses the Ethernet protocol and cannot process ATM cells.
 +
*The protocol conversion is based on the AAL5 protocol (''ATM Adaption Layer Protocol 5'').
 +
*The subscriber-side xDSL unit is $\rm xTU-R$ (''xDSL Transceive Unit - Remote'') and is located as a plug-in unit in the xDSL modem or router.  
 +
*In contrast, the $\rm xTU-C$ (''xDSL Transceive Unit - Central Office'') is located in the DSLAM (''Digital Subscriber Line Access Multiplexer'') in the exchange or in the cable distribution frame, i.e. on the network operator side.
  
 
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[[Category:Aufgaben zu Beispiele von Nachrichtensystemen|^2.2 xDSL–Systeme
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[[Category:Examples of Communication Systems: Exercises|^2.2 xDSL Systems
 
^]]
 
^]]

Latest revision as of 19:28, 25 March 2023

Standard DSL configuration

The graphic shows a possible configuration of a DSL Internet connection,

  • above the subscriber side and
  • below the components of the exchange,


which forwards the telephone signals (analog or ISDN) via the digital exchange (DIV) to the telephone network and the data signals to the Internet.

The components on the customer side, viz.

  • Splitter,
  • NTBA,
  • DSL router/modem


are the focus of the following questions.




Hints:




Questions

1

Which components separate voice and data signal at the subscriber?

DSL router/modem,
DSLAM,
splitter.

2

What is the importance and task of the NTBA?

The NTBA is only required for ISDN.
Conversion of  $\rm U_{\rm KO}$  to  $\rm S_0$  (two-wire   ⇒   four-wire).
ISDN code conversion from "MMS43" to AMI code.

3

What are the tasks of the DSL modem or router?

These units accomplish a protocol conversion.
These units contain the "xTU-R" plug-in module.
These units contain the "xTU-C" plug-in module.


Solution

(1)  Correct is the proposed solution 3:

  • The splitter is a combination of a high-pass and low-pass filter that handles the separation of the telephone signal (below 120 kHz) from the DSL data signal (above 138 kHz), or their combination.


(2)  All statements are correct.

  • For more detailed information on the ISDN basic access and especially on the network termination (NTBA), please refer to the chapter "ISDN Basic Access" of this book.


(3)  Correct are the suggested solutions 1 and 2:

  • DSL systems always use ATM (Asynchronous Transfer Mode) as the basic protocol.
  • The customers' terminal equipment, however, usually uses the Ethernet protocol and cannot process ATM cells.
  • The protocol conversion is based on the AAL5 protocol (ATM Adaption Layer Protocol 5).
  • The subscriber-side xDSL unit is $\rm xTU-R$ (xDSL Transceive Unit - Remote) and is located as a plug-in unit in the xDSL modem or router.
  • In contrast, the $\rm xTU-C$ (xDSL Transceive Unit - Central Office) is located in the DSLAM (Digital Subscriber Line Access Multiplexer) in the exchange or in the cable distribution frame, i.e. on the network operator side.