DE10254650B3 - Data transmission method e.g. for broadband access for telephone subscriber, using repeaters between successive line segments of subscriber line with at least 2 telephone line pairs - Google Patents

Abstract

The data transmission method uses at least 2 telephone line pairs, operated in parallel for simultaneous data transmission between a subscriber (LT) and an exchange (NT) and divided into line segments by intermediate repeaters (RP) for the transmitted data stream, the data transmission initiated via a preactivation process and an activation process, in which the required number of line pairs for data transmission along each successive line segment are assigned.

Description

The invention relates to a method for initiating a data transmission according to the ITU-T SHDSL (G.shdsl, G.994.1, G.hs) standard between an exchange and a subscriber, with at least two telephone line pairs connected to the subscriber parallel to the simultaneous data transfer between the exchange and participants should be used
the line segment of the telephone line pairs is divided into segments between repeaters (repeaters), through which repeaters the transmitted data streams flow, and the initiation of the data transmission by a preactivation process corresponding to the ITU-T G.994.1 standard (G.hs) ( preactivation process) and activation process.

The SHDSL standard is in ITU-T G.994.1, Series G: Transmission Systems and Media, Digital Systems and Networks "Handshake procedures for Digital Subscriber Line (DSL) transceivers ".

In modern data transmission it happens more and more often is concerned with providing a basic amount of data throughput over the data communication network data throughput, but also many times over if required to be able to increase.

For the data transmission DSL technology is widely used, the data transmission via conventional and in large Number of existing telephone line pairs allowed.

This will be done in exchanges and distribution points, as well as special DSL modems for end users installed, which carry out the data transfer.

Since there are often many wire pairs from one Exchange to the next or are transferred from a switching center to an end user, many of these line pairs are also equipped with DSL modems.

To the total transmission data rate between one participant (often referred to as NT or HSTU-R) and of the switch (LT or HSTU-C) compared to the data rate that is possible on a single line pair, you can connect set up that uses several (m) line pairs at the same time. The total transfer data rate is divided into m line pairs. For example for all m pairs the same transmission method (e.g. SDSL) is used. This is called "m-pair mode".

If the data rate ("dr") is the same on all m pairs is received an overall transmission data rate is formed by forming an m-pair group by mdr. The m-pair mode also represents a compatible extension of the already known "4-wire modes" (m = 2), in which two line pairs for data transmission be summarized.

The G.SHDSL standard with only two Line pairs are common in "G.SHDSL Overview: Standard Solution for Symmetric Broadband Access "- A White Paper, Metalink Ltd., Israel, March 2001.

At larger distances between Switching center and end user who are responsible for the respective transmission process possible Exceed distance ("lmax"), are common one or more repeaters (RP) are used. When using m pairs of cables have to be installed accordingly in each pair of repeaters. In one pair Group, each pair preferably has the same number ("r") of repeaters, since then by the Repeaters caused delays for all couples are the same. Otherwise, would the delay or runtime differences of each couple so big that they could no longer be compensated for each other.

In addition, the delay is one only repeaters bigger than the maximum difference between two pairs permitted in the known 4-wire mode. In m-pair mode, it is assumed that all m line pairs have all Take segments roughly the same physical way. Also the m each individual repeater of each segment must be at approximately the same physical location be since they're all over the common RP-HOST communicate with each other. A distance can then be used with r repeaters of l <r · lmax.

The establishment of the (physical) connections via m pairs takes place on the physical level (physical layer) (also “layer 1" called). The m-pair group then forms a single physical layer with the total data transmission rate for the higher layers. With SDSL, the establishment of the physical connection (the process flow) is divided into preactivation and activation.

This basic process is also in m-pair mode for the individual pairs. Compared to the pre-activation / activation of a single couple in m-pair mode, however, additional ones Information between LT and NT or operator and subscriber and the repeaters, if any, are replaced, e.g. B. about the number the line pairs used and the numbering of each Couples within the group.

If repeaters are present, the result is now the problem, the actual Number m of line pairs from the many lines Wiring harness with which over the entire connection (span) - d. H. about all segments - built an m-pair mode is to be transmitted from the LT to the NT side or vice versa.

The invention is based on the object to create variable and flexible process where the actual number from for data transmission line pairs used is not specified and automatically over between Repeater segments of a data transmission link a connection is built without being expensive and difficult to develop enforceable new connection protocols are necessary.

This task is accomplished through a process to initiate a data transfer solved according to claim 1.

The invention provides a method to initiate a data transfer according to the ITU-T SHDSL (G.shdsl, G.994.1, G.hs) standard between an operator and a subscriber, at least two with the telephone line pairs connected to the subscriber in parallel to the simultaneous one data transfer to be used between the operator and the subscriber, whereby the line segment of the telephone line pairs in segments between Repeaters (repeaters) divided by which repeaters the transmitted streams flow, and wherein the initiation of the data transmission by a ITU-T G.994.1 standard (G.hs) corresponding pre-activation process (preactivation process) and activation process (activation process), comprising the steps:

• - transmission a number m0 of desired in parallel line pairs to be used in the segment adjoining the subscriber the first repeater after the subscriber as a line parameter in the G.hs pre-activation process,
• - Do one Comparison of m0 with the number of ml actually in the segment between Participant and first repeater existing or released for use Telephone line pairs and reduction of the value from ml to Value of m0, if this is less than ml,
• - transmission of the value ml from the repeater to that in the line segment in Direction to the attendant segment as number ml of desired Line pairs to be used in parallel on this segment as line parameters in the G.hs pre-activation process (G.hs startup sequence),
• - Do one Comparison of m1 with the number of m2 actually in the segment after the Repeater existing or released for use telephone line pairs and reducing the value from m2 to the value of ml, if this is smaller than m2,
• - performing the last two procedural steps for each one up to the last Segment in the route leading to the switch with appropriate adjustment of ml and m2,
• - transmission of the determined value ml in the last ending at the exchange Segment to the repeater in front of it as possible number of lines m3 back up to the repeater in front of the subscriber, this being the value m3 reduced to the value m2 if this is smaller than m3 and transmitted to the subscriber as number of lines m4.

The invention proposes one appropriate education and transmission the number m of for the m-pair mode actually pairs used in the case of one initiated by a participant m-pair mode pre-activation and activation (preactivation / activation) together with information repeaters arranged in the data path. It is advantageous here that a desired value m0 for a number on lines to be seized without any knowledge of the further line structure (Number, quality, Assignment) a variable multiple assignment of line pairs in the data path for data transmission possible becomes. By passing on the adjusted value ml for the preactivated ones Data line pairs becomes an unnecessary one Initiation of a data transfer on the not needed Avoided lines. Another advantage is that Initiation of preactivation by the NT no additional Steps and agreements regarding m must be made.

An advantageous and therefore preferred The procedural step provides that the repeater directs the direction to it transmitted through the operator Value m2 with it as the line parameter compares ml in the G.hs pre-activation process and the smaller of the two numbers as m3 the next segment transmitted towards the subscriber.

In one embodiment, the Procedure provided that after performing a comparison of the number on actually existing in the segment after the repeater or the subscriber or a test for the determination of the use of released telephone line pairs the line quality (line probing), especially according to the G.hs standard. The advantage here is that the quality table determined in the process (capability list) in the transmission of the value ml from the current repeater to the direction in the line segment Mediation subsequent Segment as a line parameter in the G.hs pre-activation process (G.hs startup sequence) already exists.

An advantageous embodiment of the The procedure provides that after the transmission of the determined Value m4 to the participant the activation process (G.hs activation) with a number m5 in the direction of the operator starts.

The number m5 is advantageously less than or equal to the value m4 transmitted to the subscriber. The value of m5 is advantageously small ner than the values of m0 and m4.

Preferably, according to an embodiment of the method provided that the repeater receives the value transmitted to it for the activation process compares m5 with m4 and activates m6 line pairs, where m6 is the same m5 is if m5 is less than or equal to m4, or m6 is equal to m4 in another case is where the repeater is the line pairs for data transmission according to the G.hs standard through an activation command (activation frame) activated.

The value m6 in the activation command according to the G.hs standard is advantageously coded as follows in the case that m5 is greater than m6:
or via the respective pair thus defined 1 the m-pair group (line pair group) in one segment. (The choice

• - for the line pairs 1 up to m6 consecutive line pair identification numbers are assigned,
• - for the line pairs m6 to m5 becomes the line pair identification number of the line pair m6 assigned.

The value is preferably m6 or the line pair identification number in the activation command according to the G.hs standard (G.994.1) stored in bits 4145 to 4148.

A preferred embodiment of the The procedure provides that the repeater for data transmission line pairs to the subscriber and to the operator same line pair identification number coupled.

Other advantages, special features and appropriate further training the invention result from the further subclaims or their sub-combinations.

The invention is explained below the drawing further explained.

It shows:

1 a schematic timing diagram of a connection between a subscriber and the exchange, and

2 a tabular representation of an activation command.

1 shows an entire preactivation process and activation process (preactivation / activation) for a transmission path from a subscriber LT to an exchange NT with an interposed repeater (RP-HOST, RP). Time passes in the downward direction. The RP consists of the LT side (LT-RP), the NT side (NT-RP) and the actual host (middle box). The arrows in the segment, for example 1 between NT and LT-RP indicate the type of information that is sent via the line pairs during the preactivation, partially inactive pairs are therefore not considered, since only the sequence and the type of information transmitted are shown). The input or output arrows on the boxes (LT, NT, ...) indicate commands that also contain information.

The structure of the process flow the repeater RP is "self-mapping", that is the process can be expanded to any number of repeaters.

The transmission of the property lists (CLCxx), also “Capability lists " LT-side or NT-side and their respective versions should be here not be considered.

The preactivation of every segment begins (as for a single pair and also without RP) with the standard G.994.1 described "start up" sequence.

The G.994.1 standard is briefly referred to below as "G.hs". Then the G.hs session follows 1 , the optional line probing and then the optional G.hs session 2 ,

It is now shown in particular like the values m for the number of pairs and the numbering of the pairs within the Group transmitted to both sides (LT, NT) become.

The LT initiates the activation with the value m0 (value desired by LT). Due to cables not connected on the NT-RP side or a specification of the max. possible pairs on the NT-RP can actually be in the segment 2 possible value for m, referred to as ml be less than or equal to m0.

At the end of the G.hs session 1 of the segment 2 Both the NT-RP (and thus the RP-HOST) and the LT know the value of ml.

If a line probing (determination of the line quality according to the G.hs standard) is carried out, the first part of the G.hs session then takes place 2 ,

The results of the line testing are exchanged (between LT and NT-RP). This is advantageous so that the pre-activation of the next segment (segment 1 ) is already done with the current capability list (property list).

In the 1 are "line probing" and the first part of the G.hs session 2 Simplified in a box with the associated startup sequence.

The value ml is used to pre-activate the segment 1 started from LT-RP. The then actually possible value in the segment 1 , i.e. m2, is at the end of the G.hs session 1 of the segment 1 again known to both the NT (or in the case of several RP the next NT-RP) and the LT-RP (and thus the RP-HOST). The following always applies: m2 is less than or equal to ml.

After the startup sequence for the first Part of the G.hs session 2 is both the NT and the LT-RP and thus the RP-HOST knows the current value of m, here referred to as m3.

The respective NT side may only execute the startup sequence on m3 pairs, the NT must abort the sequence on all other pairs chen. In RP-HOST, the value m4 is now formed from the minimum of LT-RP-side and NT-RP-side m, ie m4 is the minimum of m2 and m3. The startup sequence for the G.hs session 2 of the segment 2 it starts with m4 pairs. Through the respective startup sequences and the formation of the minimum, the value in the upstream direction is finally propagated up to the LT. If there are several repeaters, m3 of each segment always represents the value for all downstream segments.

The pre-activation process is now complete in all segments completed.

The LT starts the activation. With the value m5. As a number, actually line pairs to be assigned now. Here again one of m0 or a value different from m4 if the bandwidth is now available for example, no longer in the originally requested quantity needed becomes.

The value m6 is formed in the HOST of the RP, where m6 is the minimum of m4 and m5, and in the segment 1 m6 pairs are then activated. Since m6 represents the minimum of the number of possible pairs from all segments in the case of several repeaters and thus the final number m of active pairs for all segments of the data link (span), m6 pairs are activated in the further segments in the direction downstream. The only thing that is initially unknown to the LT is m6 and must therefore be transferred from the NT-RP to the LT. m6 becomes implicit. coded in the numbering of the pairs by the NT-RP in the activation command (activation frame), as follows (if m5> m4): For m6 pairs, "normal" numbering is used 1 . 2 , ..., m6 assigned, the number m6 is always assigned for the following m5 to m6 pairs (within bits 4145 to 4148 of the "activation frame" according to G.994.1 standard, see 2 ). Example: m5 = 6 and m6 = 4 (LT would like to activate 6 pairs, but only 4 are possible over the entire span): The NT-RP then assigns the numbers 1 . 2 . 3 . 4 . 4 . 4 to the 6 Couples. The LT recognizes that the number 4 occurs 3 times and ends the activation on the two of the three remaining pairs with the number 4 Marked are. The NT-RP then also ends the activation on these pairs (without errors).

The type of numbering (order) the pairs of each segment using the line pair identification number is independent of that of another segment. Since every RP has both But he knows order on the LT and NT side "connect" pairs of identical numbers from the two connected segments.

All pairs in the segments have the number k, are thus "connected" to each other, for k = 1, ... m5. Thus, the distribution of the total data rate) on the individual pairs about the entire data path must be kept transparent.

LT

Attendees

NT

mediation

RP

repeater

Wed.

value

Claims (9)

Method for initiating data transmission according to the ITU-T SHDSL (G.shdsl, G.hs) standard between an exchange (NT) and a subscriber (LT), with at least two telephone line pairs connected to the subscriber parallel to the simultaneous data transmission between the exchange and subscriber are to be used, the line segment of the telephone line pairs being divided into segments between repeaters (repeaters) (RP), through which repeaters the transmitted data streams flow, and the initiation of data transmission by an ITU-T G.994.1 standard (G. hs) corresponding preactivation process and activation process, characterized by the process steps: - Transmission of a number m0 of desired pairs of lines to be used in parallel in the segment adjoining the subscriber to the first repeater (RP ) after the participant as a line parameter in the G.hs Vora Activation process, - performing a comparison of m0 with the number ml of telephone line pairs actually present in the segment between the subscriber and the first repeater or released for use and reducing the value of m1 to the value of m0 if this is less than ml, - transmission the value ml from the repeater to the segment in the line section in the direction of the exchange as a number ml of desired line pairs to be used in parallel on this segment as line parameters in the G.hs preactivation process (G.hs startup sequence), - Carrying out a comparison of m1 with the number of m2 of telephone line pairs actually present in the segment after the repeater or released for use and reducing the value from m2 to the value of ml if this is less than m2, - Performing the last two procedural steps for each is in the route to the switch to the last segment The corresponding segment with corresponding adjustment of ml and m2, - Transmission of the determined value ml in the last segment ending at the exchange to the repeater in front of it as a possible lei number of lines m3 back to the repeater in front of the subscriber, which reduces the value m3 to the value m2 if this is less than m3 and transmits the number m4 to the subscriber. Procedure for initiating a data transfer according to claim 1, characterized in that the repeater to the value m2 transmitted from the direction of the mediation with the transmitted to him as a line parameter in the G.hs pre-activation process Compare value ml and the smaller of the two numbers as value m3 the next Segment transmitted towards the subscriber. Procedure for initiating a data transfer according to claim 1 or 2, characterized in that after executing a Comparing the number of actually existing in the segment after the repeater or the subscriber or a test for the determination of the use of released telephone line pairs the line quality (line testing), in particular according to the G.hs standard. Procedure for initiating a data transfer according to one of the preceding claims, characterized in that after submitting of the determined value m4 to the participant in the activation process (G.hs activation) starts with a number m5 in the direction of the exchange. Procedure for initiating a data transfer according to one of the preceding claims, characterized in that the number m5 transmitted less than or equal to that of the data sink Value is m4, in particular less than m0 and m4. Procedure for initiating a data transfer according to one of the preceding claims, characterized in that the repeater sent it to the activation process Compare value m5 with m4 and activate m6 wire pairs, where m6 is equal to m5 if m5 is less than or equal to m4, or m6 is equal m4 in the other case, the repeater following the line pairs for data transmission the G.hs standard through an activation command (activation frame) activated. Procedure for initiating a data transfer according to one of the preceding claims, characterized in that the value m6 in the activation command according to the G.hs standard in the case that m5 is larger than m6 is encoded as follows: - for line pairs 1 to m6 consecutive line pair identification numbers are assigned, - for the line pairs m6 to m5 becomes the line pair identification number of the line pair m6 assigned. Procedure for initiating a data transfer according to one of the preceding claims, characterized in that the value m6 or the line pair identification number in the Activation command according to the G.hs standard (G.994.1) is stored in bits 4145 to 4148. Procedure for initiating a data transfer according to one of the preceding claims, characterized in that the repeater for data transmission line pairs to the subscriber and to the operator couples the same line pair identification number.