FI108199B - Procedure and system for forming a call - Google Patents

Description

1081 99.

METHOD AND SYSTEM FOR CALLING A CALL FIELD OF THE INVENTION

The present invention relates to telecommunication systems. In particular, the invention relates to a novel method and system for queuing resources in a local area network element in the event of an overload of the centralization interface in the local area network.

BACKGROUND OF THE INVENTION

10 Open interfaces (V5.1 and V5.2) between a local area network and a local exchange are defined in the ETS 300 324 and ETS 300 347 series standards of the European Telecommunications and Standard Institute. V5 interfaces allow physically separate subscribers to a T-15 wide area network to connect to a PBX using a standard interface. The dynamic hub interface V5.2 according to ETS 300 347-1 and 347-2 consists of one or more (1-16) PCM (Pulse Code Modulation) cables. One PCM-20 cable has a total of 32 channels or time slots, each with a rate of 64 kbit / s, i.e. a total PCM cable capacity of 2048 kbit / s. The V5.2 interface supports analogue public telephone networking, digital, such as ISDN (Integrated Services Digital 25 Network) basic and system interfaces, and other analog or digital semi-fixed terminal devices.

A Wireless Local Loop (WLL) system refers to a system in which a subscriber is connected to a p. 30 wireless network using a wireless communication system.

The subscriber connection is provided by means of a special terminal. The terminal operates in principle as a cell phone known per se, but can only be set to operate within a limited range of mobility. To implement the wireless communication system 35, mobile communication system technology may be applied, for example, 2 108199 GSM (Global System for Mobile Communications) GSM. Generally, the wireless communication system is connected to a subscriber network element of the access network, by means of which the communication system is further connected to the telephone exchange.

The subscriber network element may comprise audible and dynamically allocated resources. The subscribers can be connected to the access network element via a Remote Subscriber Stage (RSS), whereby a modular cable between 10 remote access stages and the access network element centralizes the subscribers to be connected to the access network element. Further, as mentioned above, subscribers can be connected to a subscriber network element via a wireless communication system, whereby the subscriber can be centralized at the interface between the t-15 wide area network element and the radio network. In practice, centralization here means that not all subscribers can simultaneously communicate with a subscriber network element, but only a subscriber can have ca-20 capacity.

If all resources are in use by a hub module or radio system, the problem is the success of special priority calls. When making a call from the local exchange t1-25 to the wide area network element or vice versa, the local exchange selects the link of the V5.2 interface to be used and the appropriate time interval from the link. The VC standard BCC protocol notifies the access node of the link and time slot information so that a call can be established. In the case of an outgoing call, that is, when establishing a call from the access node to the local exchange, the call may be deprived of the resource of the interface between the access node and the subscribers connected thereto due to its overload and failure. In practice, the A-subscriber does not receive a dial tone because the subscriber cannot even be connected to the access network element. In this case, the BCC protocol on the subscriber network element gives 108199 3 a negative acknowledgment to the link and time slot reservation message sent by the local exchange. A similar problem is with a call terminating in a subscriber network element. In particular, the problem arises in crisis situations, whereby subscribers simultaneously attempt to establish speech and V5 signaling channels are loaded, causing unsuccessful call attempts.

PURPOSE OF THE INVENTION

It is an object of the present invention to overcome the above problems. In particular, it is an object of the present invention to provide a new feature in the V5.2 interface such that certain priority calls can be provided with queuing feature to ensure their success.

It is a further object of the present invention to provide a method by which an operator or other telephone network operator may allocate call resources and calls or subscribers of their choice.

The present invention further relates to a system for carrying out the above method.

The invention is characterized by what is stated in the claims.

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OBJECT OF THE INVENTION

This application discloses a novel and innovative solution for queuing resources in a communication system including a local exchange, a 30 access network element, a hub, such as; · a remote subscriber stage or radio network interface for connecting a wide area network to a access node; The invention connects subscribers by means of a 35 hub connection to the access network element and from there to the local exchange.

108199 4

According to the invention, the call center is notified on a call-by-call basis to the local area network element and based on this, queuing call resources, i.e. the connection between the local area network element and the remote subscriber station or radio network interface in case of its congestion.

The local exchange may inform the access network element of a predetermined queuing time that the ti-10 broadband element waits for call resources. The queuing time can be monitored by triggering a specific timeout in the access node and upon completion of the timeout, the local exchange is notified of a call failure. Similarly, if call resources are released before the timeout ends, the local exchange will be informed of a normal acknowledgment of the connection request.

The priority classification may be stored in a state-to-network element per subscriber port, whereby specific subscribers may be given their own priority. The local center may suspend the resource queue before the timeout ends.

The system for queuing resources in a communication system according to the invention includes means for communicating a call priority classification to a subscriber network element from a local exchange on a call-by-call basis and means for queuing call resources in the event of a congestion connection. Additionally, the system may include a timer to determine how long resources are queued. ... Preferably, the subscriber network element further includes means for storing a priority classification per subscriber port.

An advantage of the present invention over known prior art ankle boots is that the service received by subscribers connected via a hub to the access node is improved. In practice, this means that. 108199 Ο In crisis and other situations where it is absolutely necessary to establish a call, the likelihood of a priority call can be improved.

In addition, the invention is applicable to both terminating and outgoing calls and is thus quite useful.

The invention is also particularly useful when both the local exchange and the local area network element are of the applicant's own production, e.g.

LIST OF FIGURES

The invention will now be described, by means of preferred embodiments, with reference to the accompanying drawing, in which Figure 1 shows a communication system according to the invention; Figure 2 shows a signaling diagram of a preferred embodiment of the present invention; Figure 3 shows a flow chart of a procedure according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

Figure 1 illustrates an exemplary system of the invention in which the invention may be practiced. The system comprises the first local center LEX and the second local center LE2. The local exchange may be, for example, a DX200 telephone exchange manufactured by the applicant. In addition, the system includes a local area network element AN 30, which is connected to local exchanges LE2 and LE2 V5.2 ί at interface V5.2. The access network element is preferably a Daxnode5000 model manufactured by the applicant. This is illustrated in the figure by the ν52 and V52 interfaces. The functionality of these interfaces and this V5.2 interface are described in more detail in the aforementioned standard series ETS 300 347, which is incorporated herein by reference. The system shown in Fig. 6 108199 · Part 1 further comprises a Remote Subscriber Stage RSS (RSS), which is coupled via a hub connection to the RSSI subscriber network test element. For example, the hub connection may be 5 single PCM wires. The remote subscriber stage connects the subscribers, in this example the PSTN subscriber SI and the ISDN subscriber S2. Although not shown here, it is clear that a telephone network may be a much larger entity than that shown in Figure 1. The network 10 may include a plurality of exchanges, access network elements, and other network components.

Figure 1 also shows in more detail part of the functional structure of the V5 interface. BCC protocol 1 allocates resources used in the call, such as time slots, and decompresses allocations from the V5.2 interface. Thus, in practice, the BCC protocol controls the use of resources in a centralized V5 interface. In the present invention, the BCC protocol is further utilized by adding a feature that announces a call priority classification to a local area network element AN when allocating a local exchange. This feature is implemented by means of the invention 1. Correspondingly, in the access node network element BCC, means 2 are provided for queuing for a speech-concentrating connection RSSI. The subscriber network element also includes a timer 3 for measuring the time allocated from the local exchange LE for queuing call resources.

Figure 2 illustrates a signaling 30 in accordance with the invention when a PSTN subscriber SI (Figure 1) begins a call setup. When the PSTN subscriber SI raises the handset, the ** V5.2 PSTN protocol transmits an ESTABLISH message, arrow 21, from the access network element to the local exchange. In the case of an ISDN subscriber, the same procedure would be followed except that the activation message would be transmitted in the Control protocol. The local exchange performs a priority class analysis for the subscriber and, on the basis of this, 108199 7 informs the BCC protocol at the local exchange LE of the possible queue length. In the privilege class analysis, for example, the subscriber data checks the subscriber privilege classification in the subscriber data. Based on the rating, the local center estimates the queuing time that is assigned to the subscriber in this situation. The BCC protocol on the local exchange side may also need to wait for a call resource from the V5.2 interface. Upon receiving the resources, the local exchange 10 transmits an allocation message, arrow 22, including a time in the access node. In the subscriber network test element AN, the BCC protocol entity receives the allocation message and the queue time is stored in the subscriber network element per subscriber port. The subscriber network-15 test element queues a call resource concentrating connection for a specified time in the RSSI allocation message if the resource is not immediately available. Upon receipt of the call resource, the BCC protocol sends an acknowledgment to the allocation message, arrow 23, on the basis of which the PA 20 knows that the subscriber has received the call resource available for the call. Thereafter, the PSTN protocol on the LE of the local exchange sends an acknowledgment, arrow 24, to the call origination message first transmitted by the access node. We further note that, although not shown here, for ISDN subscriber, the operation of the invention is essentially the same, except that the PSTN protocol is replaced by the Control protocol.

Fig. 3 is a flow chart illustrating a preferred embodiment of the invention. When the subscriber, ... picks up the handset, a notification is sent, block 31, local ·. to Lisk Center LE. Based on the notification, resource allocation from the V5.2 interface, block 32, is triggered. If a call resource is provided from the V5.2 interface, 35 privilege class analysis is performed, 33. Based on this, it is known whether the access node is being queued for 108199. In block 34, a check is made to determine whether the subscriber was given priority.

If priority subscriber access is not available to the subscriber, block 36 is moved, whereby no allocation queue time information is transmitted from the 5 local exchanges LE to the access node AN, and the only function left in block 36 is whether the hub has free call resources. If not, the pu-10 will disconnect the call, block 38. If so, normal call setup will continue, block 37.

If in block 34 the subscriber was found to have privileged calls, the allocation message is transmitted from the local exchange LE to the queued-time access node AN, block 35. Thereafter, the access node initiates a time-out block 39. If resources are available, proceed to block 41 and continue normal call setup. If no resources are available, proceed to block 42 and check the timeout status. If the timeout is triggered, proceed to block 43 and release the call. If the timeout is not triggered, return to block 40 25 and continue waiting for the resources to be released. When the * · »timeout has finally expired, the call is released.

The invention is not limited to the above embodiment only, but many modifications are possible within the scope of the inventive idea defined by the claims.

Claims (10)

A method for queuing resources in a communication system comprising a local exchange (LE), a local area network (AN) and a centralizing V5-5 interface connecting a local area network (LAN) element to a local exchange, the method comprising connecting a subscriber to a local area network (RSSI) steps: 10 informing the local area network element of the call of a call priority classification, and queuing call resources from the hub connection (RSSI) in case of its congestion. A method according to claim 1, characterized in that the local exchange informs the access node of the queue time used to queue call resources. Method according to claim 1 or 2, characterized in that time monitoring is initiated to monitor the queue time. Method according to one of Claims 1 to 3, characterized in that the access node (AN) notifies the local exchange (LE) of the release of resources, thereby continuing normal call setup. Method according to one of the preceding claims 1 to 4, characterized in that if the queuing time expires, queuing is terminated and the call is terminated. A method according to any one of the preceding claims 1 to 5, characterized in that the wired network element (AN) stores a priority classification per subscriber port. 7. A system for queuing resources in a communication system comprising a local exchange (LE), a local area network element (AN) and a centralized V5 interface (V5) connecting the local area network element to the local exchange, connecting the subscriber to the local area network characterized in that the system comprises means (1) for indicating a call priority classification from a local exchange (LE) to a subscriber network element (AN); and means (2) for queuing call resources from a concentrating connection (RSSI) in case of its congestion. System according to Claim 7, characterized in that the system comprises means (3) for indicating to the access node (AN) the queuing time expected from a call concentrating connection release. A system according to claim 7 or 8, characterized in that the system comprises a timer (4) for monitoring the elapsed queuing time. 9 108199 A system according to any one of the preceding claims 20 to 9, characterized in that the access network element (AN) includes a storage device (5) for storing a priority classification per subscriber port. n 108199 '