DE10139385A1 - Method for eliminating errors in communication connections with multiple physical connections between two stations monitors single connections in the stations deactivating a defective connection in the event of an error - Google Patents

Abstract

Data is transmitted as data divided between bundled physical connections (V1-V3). Individual connections are monitored respectively in specific stations (BS,BSC). In the event of an error, a defective connection (V1) is deactivated. Deactivation is carried out autonomously in relation to the stations as well as independently from each other and independently from other system devices. An Independent claim is also included for a communications systems device for the present invention with an interface, a processor and a monitoring device.

Description

The invention relates to a method for Troubleshoot if individual physical connections fail Communication connections with several physical Connections between two stations according to the generic terms Features of claim 1 and a Communication system device for performing such a method.

In modern communication systems, such as the Internet or radio telecommunication systems according to GSM (Global System for Mobile Communication) or UMTS (Universal Mobile Telecommunication System) are data and information between individual stations via physical connections transfer. Physical connections are included wired interfaces or radio interfaces.

In modern communication systems for reasons of Increase the transmission capacity for a data transmission often several lines operated in parallel. To do this, the Data split and over appropriately bundled lines or physical connections. in this regard Procedure for the transmission of corresponding data cells or data packets are under IMA (Inverse Multiplexing) ATM data transfer (ATM: Asynchronous Transfer Mode) or ML PPP (Multi Link Point to Point Protocol) Point-to-point protocol) for IP data transfer (IP: Internet Protocol) generally known.

With this method, the data flow is divided into several distributed physical lines. The disadvantage is that serious errors occur as soon as even a single line of a corresponding trunk group is defective. Corresponding line failures must be detected immediately and Appropriate action to be taken to a large Avoid data loss. With the common procedures for Transmission of packet or cell data over several physical Lines either have no troubleshooting mechanisms, z. B. with ML PPP, or these mechanisms are very complex, as with IMA for ATM data transfers. At IMA Signaling messages always over all bundled lines directed. This requires a correspondingly large amount of data overall to transmit and to signaling messages process. In addition, the structure of the corresponding Device blocks very complex.

To detect errors, the usual physical Detection mechanisms corresponding to layers or levels on. After detecting an error, you can take appropriate action Messages to central institutions of the Communication system are transmitted, whereupon from the central Facilities, e.g. B. an operations and maintenance center (OMC - Operation and Maintenance Center), data distribution can be set via the faulty connections. This procedure is due to the necessary transfer of corresponding messages and their processing complex and takes a relatively long time during the data on the defective physical connection be sent.

The object of the invention is to provide a method for Fixed bugs on physical connections to introduce or simplify bundled connections. This task is accomplished through a procedure to resolve Errors on individual physical connections Communication connections with the features of claim 1 or a communication system device with the features of claim 8 solved.

Advantageous configurations are the subject of dependent Claims.

The removal of individual defective connections or Lines of a bundle of lines already independent of one or offers to perform both stations at an interface a variety of advantages. A complex signaling a detected error from the stations to one or several corresponding parent Communication system facilities are not required or only for Notification of the error and the measures taken by the Station itself necessary. The is reduced accordingly Signaling and administrative effort for both affected interface-side stations as well as at the central facilities. In addition, further use the correspondingly recognized as defective physical Connection as quickly as possible through the affected interface stations are prevented, so that within Another transmission of data on defective in the shortest possible time physical connections can be prevented, which one Loss of data and / or retransmitted data reduced. Without a breakdown of the protocol, another can Use of the remaining, non-faulty physical Connections of the bundle are carried out, in the case still free physical connections the latter the bundle be added from connections. While functions on higher layers function unaffected, they ensure Functions on the lowest layers for one fast and efficient error handling.

An embodiment is shown below with reference to the drawing explained in more detail. Show it:

Fig. 1 two communication system devices with an intermediate connection and

Fig. 2 shows schematically a diagram of the protocol layers involved in this communication system devices.

As can be seen from Fig. 1, exist between individual devices of a communication system, for. B. according to the GSM, interfaces V for the transmission of data and information. These interfaces can be both wired and radio interfaces.

In the two shown Communication system devices are, for example, a base station BS and a base station controller BSC, which over the Interface V data and information with each other change. Further connections can be made between these stations or institutions BSC, BS and other institutions of the Communication system GSM exist, but are for Simplification not shown. Such an additional facility can for example, be a higher-level control device, such as them in the current communication systems for comprehensive Control are known.

The two communication system devices shown For their part, BSC, BS each have a large number of Facilities for operating the interface, but again only a part of particular interest here below is shown. From a processor P the corresponding Controlled and managed facilities and protocol layers, in particular also modules that are used as hardware and / or Software are provided.

In the exemplary embodiment shown, the interface V consists of three physical lines or interfaces, via which the corresponding physical connections V1, V2 or V3 can be established. In both communication system devices BSC, BS there are PCM30-PHY modules for controlling and managing these individual physical lines for managing the physical layer or level PCM30 PHY. Each of these PCM30 modules for controlling and managing the physical level PCM30 PHY is assigned an HDLC module for delinearizing the packets to be transmitted (HDLC: High-Level Data Link Control). While the former modules are generally assigned to level 1 , the latter modules can be assigned to level 1 or already to level 2 . The HDLC modules are each assigned PPP modules for controlling and managing point-to-point connections. This is assigned 2 (Layer 2) is usually the plane. The individual PPP modules for the individual connections V1-V3 are superordinated to an ML PPP module that distributes data over the various connections V1-V3 or manages data arriving via these various connections V1-V3. In particular, this module also distributes the data to the individual lines V1-V3.

As can also be seen from FIG. 2, the two communication system devices BSC, BS thus manage different protocol layers, the three lower elements PCM30, HDLC, PPP each being assigned to one of the physical connections V1-V3, while the further elements ML PPP and above IP are assigned to the interface V as a whole. The allocation of these individual elements to the different layers depends on the respective communication system.

The following is the procedure for a preferred one Procedure for recognizing and handling errors on a or more physical connections V1-V3 der bundled interface V described. The goal is local autonomous detection and handling of errors within everyone individual ones of the communication system devices BSC or BS, between which the interface V exists.

To realize the fastest possible error detection, error detection should be on the lowest protocol layer (physical layer). common Protocol layers / physical layers, such as B. PCM30 (Pulse Code Modulation) or STM-1 (STM-1: Synchronous Transfer Mode) appropriate error detection mechanisms. With the help of this Fault detection mechanisms can cause a line fault on a single physical line V1 on both sides of the Interface V in the corresponding Communication system devices BSC or BS independently of one another and can be recognized practically simultaneously. Mutual recognition of the line fault is particularly advantageous because at one defective line or connection V1 can no longer be guaranteed can be that a recognizing the error Communication device BS of the communication system device on the other side of the transmission link or connection V still can tell that she has detected an error. How Already found at IMA to avoid this Problems all related reports about everyone on the bundle involved lines or connections V1-V3 sent what however, adds to the disadvantageously large complexity of IMA and should be avoided here.

Additionally or alternatively, layer 2 protocols generally also offer an error detection mechanism. In the case of PPP over HDLC, this is, for example, a checksum (HDLC checksum) and PPP echo messages or PPP echo messages. In the case of ATM, a HEC field (HEC: Header Error Checksum) of the ATM cells is accordingly provided.

Both of the error detection mechanisms described above are independent of each other in the Communication system devices are available, both of which are fault detection systems detect errors related to a single line V1 and report. Such error messages are shown below described method used.

After detecting and reporting an error, one of the Lines or connections V1 becomes the respective connection from the protocol layer that the physical lines summarizes, e.g. B. IMA at ATM or, as shown, ML PPP IP data transmission, from the bundle of lines or Connections V1-V3 removed. This ensures that no data about the faulty line or connection V1 are transmitted and thereby the entire data transmission would become flawed. According to the simplest Embodiment is of course the total data rate of the bundle of Connections V1-V3 reduced.

If additional lines or connections V are free or unused, such a line can be used as an additional Line or replacement line in the remaining bundle V2, V3 can be added. Such an additional line can be, for example, a line that is connected to the Configuration of the interface V for a specific data transmission configured as an unused line for redundancy reasons can be. The inclusion of such a line can Bundles of lines keep the original data rate or win back.

The configuration shown in FIG. 1 is used as a particularly preferred exemplary embodiment. This is a multi-connection point-to-point connection (ML PPP connection) over several, in the present exemplary embodiment three PCM30 lines or connections V1-V3, as is often used in the transmission of IP data becomes. After the occurrence of an error on the first line or connection V1, this error is recognized by the PCM30 error detection mechanisms in the PCM30-PHY module on the two sides of line V1 in preferably both communication system devices BSC or BS and at the same time via a corresponding connection Processor P notified ( 1 ) On the receiver side, in the present case, for example, the base station BS, the HDLC module assigned to the defective line V1 also detects an HDLC error which is communicated to the assigned processor P in the base station BS via a corresponding line ( 2 ) ,

In addition, there are PPP echo messages or messages that the transmitter-side station, in the present case the base station Control unit sends out BSC regularly, not at the receiver-side station BS, which this in turn with the help of the PPP module, with a corresponding Notification of a corresponding connection to the processor P is forwarded. Due to the missing PPP echo notification the base station BS accordingly does not send back an echo, which in turn from the base station controller BSC in whose PPP module is determined. About a corresponding one Corresponding error message is sent to the Processor P of the base station control device BSC.

As listed above, a variety of Error detection and error reporting systems that have a fault on a single line or Detect connection V1 and to the assigned processor P of the respective communication system device BSC or BS report. In theory, only one of these is enough various fault detection devices to perform of the method described here.

The processor P in each case records the errors that are determined locally, that is to say in its communication system device BSC or BS, and carries out appropriate error handling or causes the corresponding further devices of the communication devices BSC or BS to carry out appropriate error handling. In the present case, in the event of a faulty connection V1, after a corresponding message 1-3 to the processor P, the line or connection V1 is removed locally and autonomously from the ML PPP bundle V1-V3 ( 4 ). This means that transmission errors from the faulty connection V1 can no longer have a negative effect on the transmission quality of the remaining bundle V2-V3.

Conveniently, but not absolutely necessary, can a corresponding notification about the removal of the Connection V1 from the bundle of connections V1-V3 from processor P to another, in particular higher-level instance, or Setup of the communication system to be transmitted to appropriate treatment in the communication system to be able to take into account. This particularly includes notifications an operator or a maintenance center. Is possible but also a message to the mutual, about the Interface V communicating Communication system device for further measures at a higher, higher level to be able to coordinate.

Control by the controller is also particularly advantageous Processor P, which is the addition of another, previously unused line or connection to the remaining one Bundle of connections V2, V3 enables. According to one particularly simple embodiment, it can be in the to be added to a connection previously for such purposes act reserved line. According to more elaborate However, embodiments can be any other line to the bundle be added, in which case about z. B. the a corresponding line or connection Signaling for coordination with the opposite side on the Interface V is to be made.

Claims (8)

1. A method for eliminating errors in the event of failure of individual physical connections (V1) in the case of communication connections with a plurality of physical connections (V1-V3) between at least two communication system devices (BS or BSC), in which
Data is transmitted over at least two of the physical connections (V1-V3),
in the communication system devices (BS or BSC) the connections (V1-V3) are monitored for the occurrence of errors and / or failures and
in the event of a connection error or failure, the faulty connection (V1) or faulty connections is deactivated, characterized in that
in the event of a connection error or failure in the at least two communication system devices (BS or BSC), it is caused that no data from higher layers (IP) are transmitted via the faulty physical connections (PCM30-PHY). 2. The method according to claim 1, wherein in the event of a connection error or failure, one Deactivation of the faulty connection (V1) without one Deactivation-related protocol exchange between the Communication system devices (BS, BSC) or others, especially higher-level communication system devices is carried out. 3. The method according to claim 1 or 2, wherein not faulty connections (V2, V3) for the transmission of the Data without changing the general related to them Procedure continue to be used. 4. The method according to any preceding claim, in which a deactivation of the faulty connections (V1) within at least one of the communication system devices (BSC, BS) is carried out. 5. The method according to any preceding claim, in which on the physical level (PCM30-PHY) Connection errors recorded and then the non-transmission of data via the faulty physical connection (V1; PCM30-PHY) is initiated. 6. The method according to any preceding claim, in which a connection error at the protocol level (PPP; HDLC) recorded and then the non-transmission of data on the faulty physical connection (V1; PCM30-PHY) is initiated. 7. The method according to any preceding claim, in which at the lowest protocol level (HDLC) Connection errors detected and then the non-transmission of Data about the faulty physical connection (V1; PCM30-PHY) is initiated. 8. Communication system device (BS, BSC) with
an interface (V) with a large number of physical lines for establishing physical data connections (V1-V3) to at least one other communication system device (BSC or BS) connected via the interface (V),
a processor (P) in the communication system device (BS, BSC) for controlling and managing the interface (V) and the data connections (V1-V3) thereon, data being transmitted divided over a plurality of the data connections (V1-V3),
a monitoring device (PCM30-PHY; HDLC; PPP; P) for monitoring the data connections (V1-V3), characterized in that
the processor (P) is designed to carry out a method according to one of the preceding claims and to independently deactivate individual or all data connections (V1) after detecting a corresponding error thereon by the corresponding monitoring device (PCM30-PHY; HDLC; PPP; P).