# Patent

## Title
System and method of delivering DSL services

## Abstract

A system and method for delivering digital subscriber line (DSL) service to a subscriber from a remote terminal of a telephone network. Included is a first route for delivering a telephone signal to the subscriber, and a second route for passing the telephone signal through a DSL system before delivering the signal to the subscriber. A disruptor is then used to selectively activate either the first or second route.

## Background
FIELD OF THE INVENTION
The present invention relates generally to digital subscriber lines, and, more specifically, to a new method for delivering digital subscriber line service from a remote terminal of a telephone network.
BACKGROUND OF THE INVENTION
Digital subscriber line (DSL) technology allows for high-bandwidth networking connections to be made over ordinary copper telephone lines. Traditional phone service typically relies on unshielded twisted pair (UTP) copper lines to connect homes and small businesses to the communications network operated by the telephone company (TELCO). Every one of these networks includes a central offices (CO) that services a defined region, with each CO responsible for connecting and routing calls directed to sites that reside both internal to and external of the network.
Branching out from the central office are numerous remote terminals (RT) located throughout the region being served by the CO, with each RT providing the phone service for the subscribers located within a specific area or neighborhood. One of the primary components that make up a remote terminal (RT) is a pair gain system, also known as a derived carrier system, or digital loop carrier system. In simplest terms, the pair gain system provides the TELCO with the capability to carry multiple services over a lesser number of lines, for example, five conversations over one telephone line. The pair gain system also is responsible for generating the dial tone signal one hears when they first pick up a telephone handset, indicating that an active connection is present.
FIG. 1 depicts a typical telephone connection between a pair gain system 10 of a remote terminal (RT) (not shown) and a subscriber 30. As indicated in FIG. 1, the connection between the pair gain system 10 and subscriber 30 is not accomplished directly, but instead in two legs. The first connection 10a exists between the pair gain system 10 and a cross connect block 20, while the second connection 20a is made between the cross connect block 20 and a subscriber 30. As indicated by its name, the purpose of the cross connect block 20 is to allow easy matching and connecting of two or more connections to one another, thereby facilitating the addition or removal of phone services to or from the subscriber.
To further illustrate the use of a cross connect block 20, consider the following example involving a typical modern day residence. New homes are often pre-wired to handle multiple telephone lines, i.e. six lines, to allow for future expansion. In this situation, there would be six connections running between the subscriber's house 30 and the cross connect box 20. However, if the subscriber only has two active phone lines, then only two connections representing the active circuits would run from the pair gain system 10 to the cross connect box 20. Later, if the subscriber wishes to add a new telephone line for a fax machine, a technician would have to run a new connection between the pair gain system 10 and the cross connect block 20, matching the new connection at the cross connect block 20 to the appropriate connection already present that runs to subscriber's house 30.
Note that each of connections 10a and 20a, along with the connections discussed below, although drawn as single lines in the figures, actually represent a cable pair, such as, for example, typical unshielded twisted pair (UTP) copper lines. For the remainder of the application, the terms “connection” and “cable pair” should be considered interchangeable. In view of this, it should be further understood that terminals for receiving these connections, such as can be found on cross connect block 20, are comprised of two conductors, with each conductor receiving one cable of the cable pair.
FIG. 2 depicts the same connection as previously depicted in FIG. 1. However, unlike the previous depiction, FIG. 2 provides a more detailed illustration of cross connect block 22, which is illustrated as an insulation-displacement connection (IDC) block. Unlike blocks that rely on screw-terminals or a wire wrapping technique to secure wires to the block, IDC blocks provide for a gas-tight connection without requiring the removal of insulation covering the wire. Connection is achieved once a wire is placed into an IDC block contact, and then punched down, typically via an insertion tool, pressing the wire against the contact to form the gas-tight connection. Due to ease of use and effectiveness, cross connect blocks utilizing IDC contacts have become the standard within the telecommunications industry.
As DSL technology is relatively new compared to typical telephonic communication involving analog signals, many of the remote terminals (RT) that are part of a telephone company's (TELCOs) network were not designed to allow easy incorporation of newer technology such as DSL. Accordingly, the TELCOs have had to develop ways to effectively provide DSL service to their subscribers utilizing the existing equipment on the network.
FIG. 3 depicts a typical approach to incorporating DSL service with a remote terminal (RT). The dial tone signal generated by the pair gain system 10 is directed to a splitter 50 via connection 10a. Splitter 50 also receives a connection 40a from a DSL system 40. DSL system 40 includes the equipment necessary for processing and directing the data signals back and forth between subscriber 30 and a digital subscriber line access multiplexer (DSLAM) (not shown). The DSLAM, which is operated by a service provider, takes all of the subscribers' DSL connections and aggregates them onto a single, high-density connection to the Internet. For the current illustrative example involving the integration of DSL at an RT, the DSL system may be physically mounted inside the cabinet housing the RT, or placed in its own cabinet mounted onto or next to the RT depending on factors such as size limitations and ease of access.
The role of splitter 50 is to combine the lower frequency signal from the pair gain system 10 with the higher frequency DSL data signal in such a way that they don't interfere with one another. Similarly, splitter 50 must also be capable of separating the signal sent by the subscriber 30 back into its two constituent components and then direct them back to the appropriate system. In FIG. 3, splitter 50 is depicted as an independent component separate from DSL system 40. Alternatively, splitter 50 may be incorporated into DSL system 40.
The combined signal produced by splitter 50 is delivered to cross connect block 20 over connection 50a, where it is then directed to subscriber 30 over connection 20a. Subscribers 30 can then access the higher frequency DSL signal by means of a DSL modem connected between their computing device and the telephone line(s) running throughout their residence. At the same time, standard telephones continue to have access to the lower frequency analog signals also routed over the line(s).
To accomplish the arrangement illustrated in FIG. 3, a service technician is required to go onsite and perform wiring locally at the remote terminal (RT) that is servicing the subscriber. In order to combine the signal coming from the pair gain system 10 with the DSL data signal, the pair gain system 10 that normally is directly wired to cross connect block 20 must now be rerouted so that it interfaces with splitter 50. At splitter 50, the signal from the pair gain system 10 is combined with the DSL data signal, which also runs through splitter 50. The combined dial tone and DSL signal must then be placed back into communication with subscriber 30, requiring a new connection between splitter 50 and cross connect block 20. Due to these re-wiring requirements, the telephone service of subscriber 30 is disrupted; preventing them from making or receiving any telephone calls. Further, the duration of this disruption can vary depending on the knowledge and skill of the service technician, along with the condition of the RT.
If a DSL subscriber decides he or she no longer wants DSL service, the service technician must access the remote terminal (RT) again and disrupt the connection 40a that provides communication between the DSL system 40 and splitter 50. The splitter 50 must also be removed from the system, once again disrupting the subscriber's telephone service. Additionally, during the process of reconnecting pair gain system 10 back to cross connect block 20, there is always the chance that a mistake could be made, resulting in an improper connection to exist. This can lead to subscriber 30 going without telephone service for an extended duration until the problem can be corrected.
SUMMARY OF THE INVENTION
The present invention relates to a new system and method of delivering digital subscriber line (DSL) service to a subscriber. A first route for communicates a pair gain signal from a pair gain system, through a cross connect block, to the subscriber. A second route, which partially overlaps the first route, communicates the pair gain signal from the pair gain system, through a DSL system, to the subscriber. A disruptor is then used to selectively activate one of the first and second routes.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a simplified depiction of a typical neighborhood setup for distributing telephonic communication service to a subscriber.
FIG. 2 is equivalent to FIG. 1, but with the cross connectivity block shown in further detail.
FIG. 3 is a simplified depiction of a typical setup for distributing telephonic communication service along with digital subscriber line data service to a subscriber.
FIG. 4 is a simplified depiction of a setup in accordance with one embodiment of the present invention for distributing telephonic communication service along with digital subscriber line data service to a subscriber.
FIG. 5 is an additional simplified depiction of a setup in accordance with one embodiment of the present invention for distributing telephonic communication service along with digital subscriber line data service to a subscriber.



DESCRIPTION OF THE PREFERRED EMBODIMENT
One embodiment of the present invention will now be discussed in reference to FIG. 4. Like the basic distribution setup depicted in FIG. 1, the pair gain system 10 of FIG. 4 connects to cross connect block 20 by connection 10a, while the cross connect block 20 connects to subscriber 30 by connection 20a. Through these two connections, subscriber 30 is provided with telephone service.
In order to provide DSL service to subscriber 30, a service technician accesses the cross connect block 20 that serves subscriber 30 and reroutes the telephone signal of subscriber 30 so as to combine it with a DSL signal. However, unlike prior methods of accomplishing this, according to the present embodiment the technician maintains connections 10a and 20a, thereby allowing phone service to subscriber 30 to continue during the installation of DSL service.
Instead of rewiring connection 10a, a new connection 20b is made between the cross connect block 20 and splitter 50, with connection 20b attaching to block 20 at the same terminal that receives connection 10a. This places connection 10a in communication with connection 20b so that signals traveling through one will proceed to the other. An example of a cross connect block 20 with this “double terminate” feature, where more than one connection can be established to the same terminal on the block, are the Series 2 Connecting Blocks made by Krone. A connection 40a between splitter 50 and the DSL system 40 is also established. Lastly, a connection 50a, which will carry the combined dial tone/DSL signal, is made between splitter 50 and cross connect block 20. Similar to connection 20b, connection 50a is attached to block 20 at the same terminal that attaches to connection 20a, so that these two connections are placed in communication with one another. During this entire process, the signal path made up of connection 10a, cross connect block 20 and connection 20a remains undisturbed. As such, telephone service to subscriber 30 is never disrupted.
In order to “turn on” the DSL service for subscriber 30, the service technician then modifies cross connect block 20 so as to disrupt the signal path running through block 20. As passage through the cross connect block 20 is no longer possible, the signal generated by pair gain system 10 proceeds to be redirected over connection 20b into the splitter 50, where it is combined with the DSL signal carried by 40a. The combined signal is then carried over connection 50a and connection 20a to subscriber 30, who never notices a disruption in his or her telephone service while DSL service was activated.
FIG. 5 depicts the same circuit as previously depicted in FIG. 4 with the exception that cross connect block 20 is now illustrated as an IDC cross connect block 22. As before, the service technician establishes connections 22b and 50a, which effectively adds DSL system 40 and splitter 50 in parallel to the IDC block 22. To then activate DSL service to the subscriber, the technician inserts a disconnect plug 24 designed to be received by IDC block 22. Upon its insertion, disconnect block 24 effectively disrupts or opens the signal path that previously allowed the signal from pair gain system 20 to “cut through” the cross connect block. As a result, the signal is rerouted to splitter 50 as before, thereby activating DSL service to subscriber 30 without providing any noticeable disruption in telephone service.
If subscriber 30 desires to deactivate his or her DSL service, the service technician simply repeats the process in reverse. Specifically, disconnect plug 24 is removed from IDC block 22. With plug 24 absent, the signal path through the block is once again established and the signal from pair gain system 10 takes the direct path consisting of connections 10a and 22a, instead of being redirected through splitter 50. Connections 22b and 50a can then be removed safely. As during the DSL installation stage, subscriber 30 notices no disruption in their telephone service while the DSL service is being uninstalled.
Additionally, unlike prior DSL installation methods, according to the current embodiment, connection 10a between the pair gain system 10 and IDC connect block 22 and connection 22a between IDC connect block 22 and subscriber 30 is never disrupted or removed. As a result, there is no chance of a misappropriate connection being made by the technician upon removal of DSL service, thereby significantly reducing the chances that a subscriber will have to go without telephone service due to technician error.
The DSL delivery system and method described in the above embodiments is also advantageous as it provides the technician a good opportunity to check the condition of the subscriber's line. For example, just prior to disrupting the signal path through the cross connect block by insertion of the disconnect plug, the technician can instead insert a test cord in place of the disconnect plug. This then allows the technician to “look both ways” along the line to detect signs of possible problems that could affect either telephone or DSL service.
In the above discussion, Applicant's new method and system for delivering DSL is described, for illustrative purposes, in relation to a remote terminal (RT) servicing a specific area or neighborhood of subscribers. However, the new system and method is not limited to integrating signals at or near an RT, but can also be used at various other locations within the network. For example, the new system and method could be advantageously used in a controlled environment vault (CEV) utilized by TELCOs to house underground remote terminals and other networking equipment. Alternatively, the invention as presented in the embodiments above may also be beneficially used at a central office (CO) of the TELCO.
While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation, and the scope of the appended claims should be construed as broadly as the prior art will permit.

## Claims

1. A method of delivering digital subscriber line (DSL) service to a subscriber, comprising the steps of:
(a) attaching a first end of a first connection (20b/22b) to a connect block (20/22) at a first terminal on said block (20/22) where a pair gain signal is selectively received;
(b) attaching a second end of said first connection (20b/22b) to an input of a splitter (50), said splitter selectively receiving a DSL signal;
(c) attaching a first end of a second connection (50a) to said connect block (20/22) at a second terminal on said block (20/22) where said pair gain signal is selectively relayed to the subscriber (30);
(d) attaching a second end of said second connection (50a) to an output of said splitter (50); and
(e) disrupting a signal path running through said connect block (20/22) between said first terminal and said second terminal so as to cause said pair gain signal to be diverted into said splitter (50) through said first connection (20b/22b).

2. The method of delivering digital subscriber line service according to claim 1, wherein said disruption of said signal path includes an insertion of a disconnect plug (24) into said connect block (20/22).

3. The method of delivering digital subscriber line service according to claim 1, wherein said connect block 20/22 is an insulation displacement connection (IDC) block.

4. The method of delivering digital subscriber line service according to claim 1, wherein no noticeable disruption of telephone service occurs.

5. The method of delivering digital subscriber line service according to claim 1, wherein DSL service can be stopped by removing the disruption of said signal path and then removing the first connection (20b/22b) and second connection (50a).

6. The method of delivering digital subscriber line service according to claim 5, wherein no noticeable disruption of telephone service occurs during the stopping of DSL service.

7. A system for delivering digital subscriber line (DSL) service to a subscriber, comprising:
(a) a pair gain system (10) for generating a pair gain signal;
(b) a cross connect block (20/22) for selectively receiving one or more connections;
(c) a splitter (50) for combining and separating signals, wherein one of said signals is a DSL signal from a DSL system (40);
(d) a first route for communicating said pair gain signal from said pair gain system (10), through said cross connect block (20/22), to said subscriber (30), and vice versa;
(e) a second route, partially overlapping said first route, for communicating said pair gain signal from said pair gain system (10), through said splitter (50), to said subscriber (30), and vice versa; and
(f) a disruptor for selectively activating one of said first and second routes.

8. The system according to claim 7, wherein said first route comprises:
(i) a first connection (10a) between said pair gain system (10) and a first terminal on said cross connect block (20/22), and
(ii) a second connection (20a/22a) between a second terminal on said cross connect block (20/22) and said subscriber (30);
and wherein said second route comprises:
(i) said first connection (10a) between said pair gain system (10) and said first terminal on said cross connect block (20/22),
(ii) a third connection (20b/22b) between said first terminal on said cross connect block (20/22) and said splitter (50),
(iii) a fourth connection (50a) between said splitter (50) and said second terminal on said cross connect block (20/22), and
(iv) said second connection (20a/22a) between said second terminal on said cross connect block (20/22) and said subscriber (30).

9. The system according to claim 7, wherein said disruptor disrupts said first route so as to divert said pair gain signal to said splitter (50).

10. The system according to claim 8, wherein said disruptor disrupts a signal path running through said cross connect block (20/22) between said first terminal and said second terminal.

11. The system according to claim 10, wherein said disruption of said signal path includes an insertion of a disconnect plug (24) into said cross connect block (20/22).

12. The system according to claim 7, wherein said cross connect block (20/22) is an insulation displacement connection (IDC) block.

13. The system according to claim 7, wherein no noticeable disruption of telephone service occurs during said selective activation of said first and second routes.

14. A method of delivering digital subscriber line (DSL) service to a subscriber already receiving telephone service over a first communication route, comprising the steps of:
(a) establishing a second communication route for delivering telephone service to said subscriber (30), said second communication route partially overlapping said first communication route and including a splitter (50) selectively receiving a DSL signal;
(b) disrupting said first communication route so as to selectively activate said second communication route.

15. The method according to claim 14, wherein said disruption of said first communication route is accomplished by disrupting a signal path running through a cross connect block (20/22).

16. The method according to claim 15, wherein said disruption of said signal path includes an insertion of a disconnect plug (24) into said cross connect block (20/22).

17. The method according to claim 14, wherein no noticeable disruption of telephone service occurs.

18. The method according to claim 14, wherein establishing said second communication route comprises the steps of:
(i) attaching a first end of a first connection (20b/22b) to a first terminal on a cross connect block (20/22) where a telephone signal is selectively received,
(ii) attaching a second end of said first connection (20b/22b) to an input of said splitter (50),
(iii) attaching a first end of a second connection (50a) to a second terminal on said cross connect block (20/22) where said telephone signal is selectively relayed to said subscriber (30), and
(iv) attaching a second end of said second connection (50a) to an output of said splitter (50).