MXPA02001285A - Signalling and transport of priority based control protocol messages over a switched communications network. - Google Patents

Abstract

The present invention relates to a method and apparatus for managing signaling of control protocol messages in a telecommunications node. More particularly, the invention relates to priority based signaling and transporting of control protocol messages in a telecommunications node. The present invention provides a method and apparatus for managing signaling in a telecommunications node, the node having separated BC and CC functionalities, the node also having control protocol messages for communication between the functionalities, including the steps of: allocating a priority value to a control protocol message, selectively processing the control protocol message based on the allocated priority value. Preferably, the allocated priority value is mapped to a priority mechanism of a signaling transport for transmission over a switched communications network.

Description

SIGNAGE AND TRANSPORTATION D? PRIORITY CONTROL PROTOCOL MESSAGES THROUGH A SWITCHED COMMUNICATIONS NETWORK FIELD OF THE INVENTION The present invention relates to a method and apparatus for administering signaling control protocol messages in a telecommunication node. More particularly, the invention relates to signaling and transport based on protocol message priority. control in a telecommunications node In one form, the present invention relates to a method for transmitting control protocol messages between a first entity and a second entity of a physically decomposed telecommunications node. The invention is further related to a method for transmit medium access control protocol messages on a priority basis between the first entity and the second entity. The present invention also relates to a physically decomposed telecommunications node that includes a first entity and a second entity and apparatus wherein the control protocol messages to »- and ..i¿i ??? AÍ *?». ^ ?, i, .At «.iU. priority basis are transmitted between the first entity and the second entity BACKGROUND OF THE INVENTION Due to reasons of cost efficiency, many telecommunications operators are increasingly deploying non-STM transport technologies, such as, for example, the Asynchronous Transfer Mode (ATM), Internet Protocol (IP) and Table Peló. (FR) within their networks and, therefore, require a conventionalized solution to support the existing services of today's public telecommunication networks through non-STM infrastructures of multiple vendors. In the current public telecommunication networks, the Call control functions. { CC) and carrier control (BC) are tightly coupled in the same public network protocols, such as ISDN User Part (ISUP) As a result of this tendency to operate through non-STM infrastructures of multiple vendors, it has been developing a new network architecture that required the division of CC and BC into separate protocols. As a result of the division of CC and BC, a new interface between the DC function and the BC function is exposed. A protocol is required to allow coupling between the CC and BC functions when a node is deployed in a separate environment. The International Telecommunication Union - Telecommunications Sector (ITU-T) Study Group 16 and the Internet Engineering Task Force (IETF) Megaco Working Group have developed an example of such a protocol, called an access control protocol of media. This protocol is also known as H.248. The use of H.248 is not limited to multimedia networks such as, for example, networks that comply with the ITU-T H.323 standard. The media access control protocol is intended to be used in networks where there is a physical decomposition of a traditional access function into two separate entities, namely a first entity called a Media Access Controller (MGC) and a second entity, to say, a Media Access (MG) In the ITU-T Study Group 16 and in the Megaco IETF Working Group the CC function is known as an MGC and the BC function is known as MG. Both MGC and MG operate in a "client-server" relationship, where the MGC sees itself as the server and controls the call logic of the physical connections in the MG The MG is seen as the client, managing the physical connections of the medium in response to orders sent from the MGC. When reference is made to a physically decomposed telecommunications node this is equivalent to referring to a separate BC and CC telecommunications node The examples of information passed from the MGC to the MG in H.248 protocol include information for ordering a circuit connection telephony in the MG to another ° telephone circuit, which is when the MGC receives a request for a telephone call to be established, the information to order that tones be inserted in the MG media stream and information to order the disconnection of the circuits in the MG. Examples of information passed from the MG to the MGC in the medium access control protocol are accounting for information about the call duration, or statistical information on the current use of the media connections. The type of information being carried in the messages. H.248 signaling is varied and can be formed into categories in static data and dynamic data. The static data belongs to physical characteristics of an MG, for example passing information about the characteristics of a termination in an MG (which is a function of the AUDIT command), or the static data defines the functions that the MG has the ability to use The dynamic data, on the other hand, belongs to individual call connections such as the MG reporting call events observed in the MGC ( for example, order to NOTIFY), or the MGC ordering the MG to modify terminations / contexts in accordance with the state of the call, for example, order s ADD, SUBSTRATE, MODIFY The AUDIT order can also be used by the MG to determine information about individual call connections, for example charge and statistics data belonging to an individual termination In a traditional telephony application, the amount of data passed between the MGC and MG is potentially very large and varied In large-scale applications such as that for a local telephony exchange that could handle tenths connections of thousands of subscribers, it may be required to pass many thousands of messages per second on each link. H 248 signage from MGC / MG The signaling capability, therefore, becomes an important one for telecommunication operators that are looking for as much as possible to maximize the production of The most important of these is that it is the most important. "-. - - - f? - mi Ti ii lpJiiiiiÉ-llilIhilÉlíl 'MuÉlr' k? ' "- • - *" * - • * call, in order to increase revenue, such as the use of signaling link, in order to minimize the costly hardware.When the signaling link is used on a " first to come, first served ", the link characteristics may suffer in that for example, during a busy period, with many calls being handled by the MGC and MG it is important for the operator that calls reach a chargeable state and be executed successfully That is, the dynamic data messages of H.248 are all completed quickly and satisfactorily. If a static data message is inserted into the signaling link, it is highly probable that some of the dynamic data orders will fail due to the signaling link overload Calls subsequently will fall and call revenues and system performance statistics will decrease.

SUMMARY OF THE INVENTION An object of the present invention is to overcome or improve at least one of the problems of the prior art. Additionally, it is desirable to provide a method and apparatus for transmitting control protocol messages between entities of a physically decomposed telecommunications node. which improves or overcomes one or more of the aforementioned disadvantages. It would also be desirable to allow transportation d? protocol control messages, such as media access control protocol messages, between entities of a physically decomposed telecommunications node, such as a media access controller and a physically disabled access media access, without causing failure of various orders due to the overload of a particular signaling link. In one aspect, the present invention provides a method for managing signaling in a telecommunications node, the node having separate BC and CC functionalities, the node also having control protocol messages for communication between functionalities, the method of administering signaling including the steps of. distributing a priority value to a control protocol message selectively processing the control protocol message based on the distributed priority value. In another aspect, the present invention provides a telecommunication node having separate BC and CC functionalities and having messages of control protocol for communication between the functionalities an apparatus for managing the signaling between the functionalities including • a means of priority distribution for distributing a priority value to a message d? control protocol a processing means for selectively processing the control protocol message based on the distributed priority value. In essence, the present invention stems from the realization that the capacity of a signaling link in a separate BC and DC telecommunications node can be increased by applying a priority mechanism in the media access control protocol. In a further aspect of the invention, there is provided a method for transmitting control protocol messages on a priority basis between a first entity and a second entity of a separate BC and DC telecommunications node, wherein the media connections in the second entity are controlled by the first entity, the method including the steps of creating a control protocol message in one of the entities; assign the control protocol message a priority value, transmitting the control protocol message through a switched communications network to the other of the entities, and wherein the other of the entities, during receipt of the control protocol message, selectively processes the message of control protocol based on the assigned priority value The first entity can be a signaling control access and resource, such as a media access control, and the second entity may be a media termination access, such as a media access. The control protocol message may be a media access control protocol message. The telecommunications node can be a physically decomposed means access Priority - / values can be assigned to orders, actions and transactions that are part of each message The first entity or the second entity can accept each priority value for each message as an entry for sending the message and mapping the priority value to a signaling transport mechanism such as IP, ATM or MTP3 to transport each message between the first and second entities Priority values can be assigned dynamically on a basis by situation and / or a base in order In accordance with another aspect of the invention ST provides a separate BC and CC telecommunication node that includes a first entity and a second entity where the media connections in the second entity are controlled by the first entity, the node including a means for creating a control protocol message and assigning a priority value to the control protocol message in one of the entities, a means for transmitting the control protocol message to through a communications network switched to the other of the entities where during the receipt of the control protocol message the other entity selectively processes the control protocol message based on the assigned priority value. In this manner, the messages of control protocol are transmitted through a commuted communications network between entities of a telecommunications node physically decomposed on a priority basis to substantially prevent the failure of various orders where the signaling link is interrupted BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in a preferred embodiment, by way of example only, with reference to the drawings that they are accompanied, where. Figure 1 is a schematic representation of interfaces and functions of an H.323 access; Figure 2 is a schematic representation of a modality of a physical decomposition of a telecommunications node, such as access H.323 of Figure 1, where it is decomposed into an MGC and an MG, Figure 3 is a graphic representation of various parts of a control protocol message, such as a media access control protocol message exchanged between the MGC and an MG of FIG. 2; And Figure 4 shows an example list of order messages transmitted between the MGC and MG that have assigned them a priority value.

DETAILED DESCRIPTION OF MODALITIES Although reference is made herein to access functions in accordance with ITU-T Recommendation H.323, this is for example only and the invention can equally be applied to physically decomposed access functions modalized in networks of ¿¿Ési < < ^ lú Wml? ai * ~ > * ~ > ~ '? * ~ -' "'í-' ¿'- - ••' - -A * ~ i + * ^ < < t < ** -» »*** *. - s * -fc ^ ifaüílAJ Independent Support Call Control, BICC and Session Initiation Protocol, SIP With reference to Figure 1, a representation of a group of features and functions of a multimedia access 1 that operates in accordance with ITU-T recommendation is shown H 323 Multimedia access 1 is an endpoint in an H.323 multimedia network that provides two-way real-time communications between terminals in the packet-based H 323 network and other ITU-T terminals in the communications network of switched circuit network such as ISDN or PSTN terminals or other access ri 323 While the present invention will be described in relation to multimedia accesses it should be understood that this is equally applicable to terminals, access controllers, multi-point controllers, processors multiple points and other telecommunications nodes that form a part of a multimedia network Multimedia access 1 includes signaling termination points 2 3 and 4 respectively acting to provide a interface between RAS signaling messages H 245 signaling messages and H 225 signaling messages in an H 323 network and an access control logic unit 5 An additional signaling termination point 6 acts to provide an interface between SCN messages of Signaling Associated with Installation and control unit d? access. A signaling transport termination point SCN provides an interface between the signaling termination point 6 and an SCN network. The functions of access control 1 are divided between high layer resource control functions in the access control logic unit 5 and lower layer resource control functions provided by an access device 8. A packet / circuit component 9 terminates channels of SCN medium that converts media streams to packet-based media in the packet network interface. The Y indicates the external packet interface and the Z indicates the external SCN interface. The functionality of media access 1 can be physically broken down into a first entity, represented as a media access controller, and a second entity represented as a media access. Figure 2 shows an example of said physically decomposed multimedia access 10. In this example, the FAS SCN services provided by terminating points 6 and 7 are isolated, together with the access device function, in a media access 12. The H.323 signaling is retained in a media access controller 14 In general, it can be said that media access 12 acts to convert media provided from one network type to the required form in another network type MGC 14 controls those parts of the call state belonging to the network. connection control for media channels in media port 12 From figure 2 it can be seen that the physically decomposed multimedia access 10 exposes a device control device A between the access control logic unit 5 and the functions 8 of access device, as well as an SCN signaling interface C between the access control logic unit 5 and the SCN termination functions 6 and 7 The messages, therefore, are required to be exchanged in the interchanges A and C between the MGC 14 and the MG 12 through an external telecommunications link The control protocol d? media access or H.248 protocol defines a general framework for exchanging these messages between elements of a physically decomposed multimedia access The media access control protocol describes resources in the BC function of MG 12 in terms of contexts and terminations A termination it represents a physical end point and different characteristics can be assigned, for example the type of transport (circuit, IP, ATM) or type of medium or codec (GSM, G.711). A termination in other words is an entity that resorts and / or adds up in media streams. In the case of a multimedia conference, a termination describes all media streams that originate from or are sent to a user. A context, on the other hand, groups a number of terminations into a single conference, to describe a path or call between the BC function or an internal function to the BC function. The commands from MGC 14 to MG 12 are grouped into transactions, each one of which is defined by an ID transaction. Transactions consist of one or more actions where an action considers a series of orders that are limited to operate within a single context. Consequently, each action must typically specify a context ID An example of a transaction 20 is shown in figure 3 , where it consists of three particular actions 22, 24 and 26. Within each action there is a number of orders as shown. The H.248 protocol provides commands to manipulate the logical entities of the protocol connection model. Contexts and Terminations Orders provide control at the highest level of granularity supported by the protocol. For example, orders exist to add Terminations to a Context, modify Terminations. subtract Terminations from a Context, and audit properties from Contexts or Terminations. The commands provide complete control of the properties of Contexts and Terminations. This includes specifying what events a Termination should report and what signals / actions should be applied to a Termination. The examples of the commands used in H.248 include the Add command that adds a termination to a context. This order is generally used to create new endings and add them to a context. This context can also be created implicitly when a termination is added to a new context. The Modify command modifies the properties of a termination and could also be used to change the properties of a context. The Subtract command disconnects a termination from its context and returns statistics in the termination pa icipation in the context The Move command automatically moves a termination to another context and the Audit command returns the properties values of the terminations and access capabilities media. The Audit order can also be used to consult the properties d? a context Finally, the Notify command allows the MG to inform the MGC of the occurrence of events in the MG, in the Figure 4 shows a frame 30 specifying a number of example orders in the first column that are transmitted between the MGC and the MG. All orders except the Notify Order and Service Change Order are sent to the MG by the MGC. The Notify and Change Service orders are sent to the MGC of the MG. The Audit order can also be sent from the MG to the MGC. A priority mechanism in the H.248 protocol is applied to each specific order. Each message sent from the MGC or the MG, therefore, a priority value would be distributed in accordance with its perceived importance in the MGC / MG system, as specified in the second column in the table. The MGC, or MG depending on the order would take this priority setting as an input to send a message and map it to the appropriate signaling transport mechanism Assuming that there is a wide variety of signaling transport mechanisms for H248, these priority values it would be mapped by the MGC and MG in priority mechanisms existing in each transport and consequently transported accordingly. By way of example, to transport Internet Protocol (IP) - 1 of H.248 messages the priority values would be mapped by the MGC / MG to the IP "Service Type" values. For transport of Asynchronous Transfer Mode (ATM), priority values could be mapped in combinations of Virtual Circuit Identifier / Virtual Path Identifier (VCI / VPI). For the message transfer part (MTP), for example, in particular the level 3 transport mechanism (MTP3), the priority values could be mapped to different Signaling Link Set (SLS) values. Examples of these maps are shown in the table in figure 4. Four different order priority values are assigned where priority 1 is the highest priority and priority 4 TS the lowest priority. As an example, for IP, the ADD order has priority 1 and is mapped to the Type of Service field in the header in the "immediate, minimize delay" category. For ATM to map to the header portion of the packets under the VCI / VPI fields In this particular example there are three different types of vci / VPIs, where x, y, and z are to carry K.248 messages. For MTP3 there are two different types of priority being, a, b and the ADD order is done through the VCI / VPI represented by the value x. For the IP header there are 32 different Ü U U U f át át...... - - -,,,,,,,,,,,,,, ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^. If each of the orders are combined together into actions, as shown in Figure 3, an additional mapping is required in the seventh MGC / MG and that is to provide the particular action with a priority based on the priority of the contained orders. within that action. For example, the action will have the same priority as the lowest priority of all the commands contained within that action. Similarly, if these actions are combined into transactions, then an additional mapping is required, for example, the transaction may have the same priority as the lowest priority of all the actions contained within the transaction. The above examples of commands in Figure 4 assume a static priority configuration. Alternatively, in particular situations, a more dynamic priority configuration is required. For example, in case of severe congestion between the MGC and MG, it is not desirable to give higher priority to dynamic data orders, such as Add, Modify or Subtract since this would lead to worse congestion due to overload in the particular signaling link, Therefore, in this situation the priority would be required to be provided to an order of : 0 - eetático data, such as Change of Service in order to clarify the freeze as quickly as possible, The Change of Service order allows the MG to notify the MGC that a termination or a group of terminations is about to be removed from service and has just returned to service. In this way, the MGC / MG would be provided with an option to adjust the priority dynamically on a per-order basis, per situation. In this way, each message is assigned a specified priority level, depending on the application used by the control protocol. media access or H.248 protocol In particular, the commands used are assigned with a particular priority level according to the situation at the time it is assigned. The media access control protocol would then map the priority it has received from its user to the priority setting associated with the particular transport mechanism used, since it is, for example, IP, ATM or MTP3. Assigning orders with a particular priority on a dynamic basis prevents any low priority messages from distributing link characteristics. This will help existing systems, based on STM, ATM or systems that have similar mechanisms to adapt softly to new network architecture that allows an entity, which is the MGC to control the media connections in another second entity, being the media access ^ • fc ^ < ^^ * rfe ?????????????????????? ^ - »- ^ '^ ^ * - J ^« M ^! AB ^ ALMas ^ J¿ »JMlfe ^ a ^

Claims (7)

1. - A method for managing signaling in a telecommunications node, the node having separate BC and CC functionalities, the node also having a control protocol message for communication between the functionalities, the method of managing the signaling including the steps of: distributing a value of priority to a message d? control protocol selectively process the message of the control protocol based on the distributed priority value.

2. A method according to claim 1, wherein a priority value is distributed to each control protocol message.

3. A method according to claim 1 or 2, which further includes the steps of: accepting the priority value as an input to a functionality to transmit, and; map the priority value to a priority mechanism of a transport signaling. Four . - A method according to claim 1, 2 or 3, further comprising the step of transmitting the control protocol message through a switched communications network. ^? ^ m ^ S ^^ i ^ a & ^ lt? iA kie ^ áiiMIlk ^ - ^ aLja ^ JUa ^. 5 - . 5 - A method according to claim 3 or 4, wherein the signaling transport is IP, ATM or MTP3. 6. A method according to any of claims 1 to 5, wherein the control protocol message includes transactions. 7 - A method according to claim 6, wherein the transactions include actions 8.- A method according to claim 7, wherein the actions include orders 9.- A method according to claim 8, wherein the priority values are distributed to orders, actions or transactions 10 - A method according to any of the preceding claims, wherein a priority value is dynamically distributed 11 - A method according to claim 10, wherein a value of priority is distributed on a per situation basis 12 - A method according to claim 10, wherein a priority value is distributed on a base per order 13 - A signaling method within a telecommunications node, the node having Í?.? A. * ^. TAá | ái | fir1r. < Mf | T | ¡| ,, -, | r nH ili 'TTiltÉ i i i' i i i i 1 BC and CC separate functionalities, the node also having control protocol messages for communication between the functionalities, the signaling method including the steps of; administering the control signaling according to the method according to any of claims 1 to 12, and transmitting the control protocol messages through a switched communications network. 1

4. A method for transmitting control protocol messages on a priority basis between a first entity and a second entity of a separate BC and DC telecommunications node, wherein the media connections in the second entity are controlled by the first entity, the method including the steps of: creating a control protocol message in one of the entities; assigning the control protocol message a priority value, transmitting the control protocol message through a switched communications network to the other of the entities; and where the other entity, upon receipt of the control protocol message, processes selectively the control protocol message based on the assigned priority value. 1

5. In a telecommunications node having separate BC and CC functionalities and having control protocol messages for communication between the functionalities, an apparatus for managing the signaling between the functionalities that includes a means of distribution or priority assignment for assign a priority value to a message d? control protocol, a means of processing to selectively process the control protocol message based on the assigned priority value. 16 - An apparatus according to claim 15, wherein the priority assignment means assigns a priority value to each control protocol message. 17 - The apparatus according to claim 15 or 16, wherein the node is an H.323 access. 18. The apparatus according to claim 16, wherein the CC functionality resides in a Media Access Controller. 19 - The apparatus according to claim 17 or 18, wherein the BC functionality resides in a Media Access. 20. The apparatus according to claim 17, 18 or 19, wherein the control protocol shake is a Media Access control protocol message 21. The apparatus according to claim 20, wherein the Control protocol message includes transactions. 22. The apparatus according to claim 21, wherein the transactions include actions. 23. The apparatus according to claim 22, wherein the actions include orders. 24. The apparatus according to claim 23, wherein the priority distribution means assigns priority values to orders, actions or transactions. 25. The apparatus according to any of claims 15 to 24, wherein the priority distribution means includes dynamic allocation means for dynamically assigning a priority value. 2

6. The apparatus according to claim 25, wherein a value of priority on a basis by situation. 27 - The apparatus according to claim 25, wherein a priority value is assigned on a base in order. 28 - In a telecommunications node that has separate BC and CC functionalities and that has control protocol messages for communication between the functionalities, an apparatus for signaling among the functionalities that it includes: an apparatus for managing the signaling between the functionalities in accordance with any of claims 15 to 2

7. 29 - A telecommunications network including an apparatus according to any of claims 15 to 28 - A telecommunications system including an apparatus according to any of claims 15 to 28 31. - A method as described herein. - A network, system, protocol or apparatus as described in the present 33 - A separate telecommunication node of BC and CC that includes a first entity and a second entity, wherein the media connections in the second The entity is controlled by the first entity, the node including: a means for creating a control protocol message and assigning a priority value to the control protocol message in one of the entities; means for transmitting the control protocol message through a switched communications network to the other of the entities; wherein upon receipt of the control protocol message, the other entity selectively processes the control protocol message based on the assigned priority value. 1 ¡M t ililii i i r ¡[liíhiiiiiii iiiiiiíii) - * a. * M - itd -. ^ ^ HUU A AA »^ ,,! . AJ ^