Method and device in a coupling node for a tele system

SWEDEN ds) PATENT WRITING (13) C2 <11) 522 271

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(19) SE (51)

International class ⁷

G06F 9/46, H04Q 11/04

PATENT AND REGISTRATION (45) (41) (22) (24) (62) (86) (86) (83)

Patent filed Application widely available The patent application was submitted on expiration date

Tribal application number

2004-01-27

2002-01-06

2000-07-05

2000-07-05

International filing day

Filing date for European patent application Deposit of microorganism (21) Patent application number 0002546-0

Application received as:

Swedish patent application completed International patent application with number □ converted European patent application with number (30) Priority information (73) PATENT HOLDER Telefonaktiebolaget LM Ericsson (publ),

126 25 Stockholm SE

Lars-Göran Petersen, Tumba SE, Ulf Ekstedt, Saltsjöbaden SE, Patrik Wiss, Stockholm SE, Gunnar Larsson, Tumba SE Ericsson AB

PROCEDURE AND DEVICE IN CONNECTING NODE FOR A TELEVISION SYSTEM (56)

WO Al 0 028 778 (H04Q 11/04), US A 6 009 507 (G06F 17/00) (57) SUMMARY:

(72) INVENTOR (74) REPRESENTATIVE (54) TITLE

The present invention relates to a switching node (MG1) for coupling connections in a telecommunications system, which comprises networks (N1, N2) of different signal formats. The switching node has switch and trunk functions (CP21, CP23) corresponding to the signal formats and telephone functions, for example encoder / decoder (F21) and echo extinguisher (F22) which the node can connect to a connection through a switch (PSI). The functions are supported by circuit boards (CB1-CB9) in magazine (SR1) and the circuit boards have signal processors (DSP11-DSP13) with access points (SAP11-SAP14). The selector seeks out one of the signal processors to handle one of the functions. If the processor has sufficient free memory space in its data memory and instruction memory and sufficient processor capacity, this processor is selected. Otherwise, a new processor is sought which is tested in the same way.

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The numbers in brackets indicate international identification code, INID code. Letters in clamps indicate international document code.

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SUMMARY

The present invention relates to a switching node (MG1) for coupling connections in a telecommunications system, which comprises networks (N1, N2) of different signal formats.

The switching node has switch and trunk functions (CP21, CP23) corresponding to the signal formats and telephone functions, for example encoder / decoder (F21) and echo extinguisher (F22) which the node can connect to a connection through a switch (PS1). The functions are supported by circuit boards (CB1-CB9) in magazine (SR1) and circuit boards have signal processors (DSP11-DSP13) with access points (SAP11-SAP14). The selector seeks out one of the signal processors to handle one of the functions. If the processor has sufficient free memory space in its data memory and instruction memory and sufficient processor capacity, this processor is selected. Otherwise, a new processor is sought which is tested in the same way.

Publication figure: Figure 8

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TECHNICAL FIELD

The present invention relates to a device and method for connecting a connection in a switching node in a telecommunications system and thereby utilizing the switching node's processor resources in an efficient manner.

BACKGROUND OF THE ART

Telecommunication systems that are composed of several different types of telecommunications networks have emerged. The networks can be both circuit switched and packet switched and may have different types of signal formats. The networks, even the packet switched, are capable of transmitting information in real time and in some cases offer high quality of services provided, such as high availability, good audibility and uninterrupted communication. However, the networks are expensive for operators to administer if the high quality requirement is to be maintained. These costs can be reduced if so far telecommunication networks are replaced with a completely new, packet switched network. However, this would entail capital destruction. Efforts have therefore been made to create a gateway through which certain networks can be interconnected while maintaining good quality of services.

A gateway that meets the above requirements becomes quite complicated. It has therefore been important to make the gateway efficient in the sense that many connections can be connected through a certain gateway and that its combined resources can be fully utilized.

In an article by Stella Sofianopoulou, Optimum Allocation of Processes in a Distributed Environment: A Process-to-Process Approach in J. Res. Soc. Vol. 41, no. 4, pp. 329-337, 1990, are theoretically discussed how in a telecommunication system to choose processors in order to process a number of processes optimally. The processes being processed are partly connected to the connection of a telephone connection and partly to the internal processing of the processors.

522 271 work. More specifically, the article addresses how many processors are needed to effectively handle a certain number of processes.

U.S. Patent No. 6,009,507 discloses a computer system having a number of signal processors attached to a host computer. One of the signal processors is subsequently assigned a number of tasks so that the processor is utilized to the maximum. When fully loaded with a task, the system appoints a new processor to complete the task.

International patent application WO 99/35773 describes a system of processors that each process call connections. The data for the connections is distributed among the processors by a resource manager.

European patent application EP 0 366 344 B1 describes a system with a plurality of nodes with each processor. These should process requests to perform certain tasks. The processors have a certain maximum capacity and the total workload is distributed using addresses to the processors. The addresses are recorded on a list and to avoid overloading the processors, a processor is removed from the list as its load exceeds a threshold and is again recorded on the list when the load has dropped below another threshold.

DISCLOSURE OF THE INVENTION

A telecommunications system usually includes different telecommunications networks that are interconnected through nodes. When connecting a connection in the telecommunications system via these switching nodes, sequential order functions in the node are necessary for the connection. The present invention addresses a problem of utilizing node processors efficiently in the management of these functions.

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Another problem that is being addressed is to use the processors in the node in a flexible way.

Another problem that is being attacked is also to utilize the node's communication resources effectively.

The problem is solved by seeking out a processor, which is a suitable candidate for handling at least one of the functions in the sequence of the connection in question. It is then examined whether the processor has sufficient capacity to handle the function. If not, a new processor is selected as a candidate, which is examined in a similar manner.

the connection features.

Specifically, the problem is solved by examining whether the processor has sufficient space in its instruction memory and in its data memory, and that it has sufficient processor capacity to perform the function itself. If so, that is, the processor can be assigned to the function, the function's computer code is loaded into the processor. The processor does not need to be pre-allocated to handle some of the functions, but the processors in the node can be examined and assigned as communication resources are resolved by selecting the functions so that the communication paths between the functions are short.

these must be connected to utilize the node's internal exits

The problem

Thus, a general object of the present invention is to connect a telecommunication connection between different networks via at least one switching node and thereby utilize the node's processor resources efficiently in the management of the functions.

Another purpose is to be able to utilize the node's processor resources in a flexible way.

The nodes are made up of printed circuit board magazines which support the processors. A further object is hereby possible

522 271 utilize processor capacity from all circuit boards as a common resource in the node to handle the functions.

Yet another object is to be able to utilize the processors in one of the nodes to handle functions from another of the nodes.

Another object is to utilize the node's internal communication resources efficiently.

The invention has the advantage that the total processor capacity in the nodes can be utilized.

Another advantage is that the code for the function in question does not need to be stored permanently in a processor. The code can instead be downloaded into the processor if needed for a connection and the processor can then be used for other functions or purposes.

Another advantage is that the number of different types of printed circuit boards can be reduced compared to known solutions.

Another advantage is that the node's internal communication resources are utilized efficiently.

The invention will now be described in more detail with the aid of preferred embodiments and with reference to the accompanying figures.

DESCRIPTION

Figure 1 shows a view of a telecommunications system;

Figure 2 shows a block diagram of a switching node;

Figure 3 shows a flow chart of connecting a connection from a calling subscriber to a gateway;

Figure 4 shows a flow diagram of connecting a telephone function in the connection of Figure 3;

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Figure 5 shows a flow chart for connecting the connection from the gateway to a further node in the telecommunications system;

Figure 6 shows a flow chart for connecting a connection over more than one gateway in the telecommunications system;

Figure 7 shows views of portions of the gateway;

Figure 8 shows a block diagram of the structure of a portion of a gateway;

Figure 9 shows a block diagram of an alternative structure of a portion of a gateway;

Figure 10 shows a block diagram of sequential engagement of functions in a connection;

Figure 11 shows a block diagram with a hierarchical address;

Figure 12 shows a block diagram with a hierarchical address;

Figure 13 shows a flow chart for selecting a function in a connection;

Figure 14 shows yet another flowchart for selecting a function in a connection;

Figure 15 shows a further flowchart for selecting a function in a connection; and

Figure 16 shows a flowchart to investigate whether a processor can handle a function.

PREFERRED EMBODIMENTS

Figure 1 shows, as an example, a view of part of a telecommunication system TS. This includes a first network N1, which is an ATM network, a second network N2, which is an IP network, and a third network N3, which is an STM network. The term ATM stands for Asynchronous Transfer Mode. The second network N2 is partly connected to the first network N1 through a first gateway

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MG1, partly connected to the third network N3 through a second gateway MG2. The telecommunications system also includes a control server SI for controlling connection of connections. The server S1 is connected to the gateway MG1 via a connection C1 and to the gateway MG2 via a connection C2. The figure also shows that additional servers, for example the server S2, are part of the telecommunications system and in the example are connected to the gateway MG1. In the network NI there is a first telephone subscriber A1 with a mobile phone MP1, which can be connected to its network through a base station BS1. The base station is connected to the gateway MG1 via a connection C31. In the network N2 there is a second subscriber B1 with an ordinary, circuit-switched telephone apparatus POT1, which is MG1 via a television exchange VX1. the telephone set POT1 can be connected to each other via the gateway MG1 so that the subscribers A1 and B1 can talk to each other. In the third network N3 there is a third subscriber B2 with a telephone POT2 which is connected to the second gateway MG2 via a switch VX2. Subscriber B2 can be connected to the other subscribers via the MG2 gateway. How the MG1 and MG2 gateways are constructed and how the connection is performed will be described in more detail below by some examples.

connected to the gateway The mobile phone MP1 and

Figure 2 shows the logical structure of the gateway MG1. This has two main parts, a telephone function part TF1 and an interface block CP2. The telephone function part comprises a function block F2 which has function devices with telephone functions F21-F28 which are used in telephone connections. According to the example, the function F21 is an encoder / decoder, the function F22 is an echo canceller, the function F23 is a modem, the function F24 generates a tone signal which commands a ring signal from a subscriber, the function F25 is a message function which generates spoken standard messages, the function F26 enables subscriber can speak a voice message, the function F27 converts between digital ulag and A-team and the function F28 provides the function

522 271 conference connection. The telephone function part TF1 also includes a signal processing unit CP1, which is connected to the server S1 through the connection C1, and a first control unit CC1 for controlling the connection of a connection internally in the gateway MG1. The first controller CC1 is connected partly to the signal processing unit CP1 through an interface 1 and partly to the function block F2 through an interface 2. The function block F2 has a second control unit RC2 which is connected to the functional devices with the functions F21-F28 through an interface 6 and which controls the allocation of the resources in these functions. The different phone functions are available in several editions.

Interface block CP2 comprises a physical line interface CP20 having external connections C31, C32, C41 and C42. The block CP2 includes a signal format converter CP29 functional devices with switch and trunk functions CP21-CP27 to handle transformations of different signal formats on signals exchanged via the external connections. The block CP2 also has a third controller BC3, which is connected partly to the signal format converter CP29 through an interface 7 and partly to the second controller RC2 via an interface 1/02 and is also connected to the first controller CC1 through an interface 3. According to the embodiment, interface block CP2 following switching and trunk functions. The CP21 function is an IP path selector, the CP22 function terminates IP, TCP and UDP, the function CP23 connects ATM cells, the function CP24 terminates AAL2 (ATM Adaption Layer type 2), the function CP25 connects AAL2 packets, the function CP26 connects STM channels and the function CP27 terminates STM channels. The switch and trunk functions are also available in several editions.

The above-mentioned parts of the MG1 gateway have the following functions.

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The signal processing unit CPI exchanges signals M1 with the server SI via connection C1. The unit handles security and authorization functions, confirms that messages have been received, records incoming and outgoing messages and announces to the server when status changes in the gateway have taken place. The signal ML has two parts, one part with an address header and one part with the content itself, so-called payload, which is divided into different packages. The signal processing unit CP1 separates the address head on a received signal and therefore sends the intended packets on to the first control unit CC1 via the interface 1.

The first control unit CC1 receives the signal packets, a signal M2, from the signal processing unit CP1 and requests with guidance thereof the telephone functions F21-F28. The first controller activates or deactivates external connections as indicated by the signal M2 and activates or deactivates internal connections between the telephone functions and the external connections endpoint.

The second controller RC2 handles the aforementioned telephone functions F21-F28. The other controller has information on how many editions of a particular telephone function are available. It also has information on where the functions are located in a structure of carriers that carry the functional devices, that is, the control unit has the function addresses of the telephone functions. The first controller CC1 requests, through a signal M3, one of the telephone functions of the second controller. The second control unit sends a message M4 with a function address for the telephone function, including an indication of the location of the function on the carriers, to the first control unit.

As shown in the description above, the telephone function part TF1 has the two internal interfaces 1 and 2. The purpose of the interface 1 is to keep the reception and processing of the message M1 itself separate from the operations which

522 271 message causes. Through interface 2, the first controller CC1 can reserve the telephone functions F21-F28 for a connection or release them when they are no longer needed for the connection.

In the interface block CP2, the line interface CP20 has different types of physical interfaces with different transmission speeds 1.5, 2, 34 or 155 Mbps. The third controller BC3 can perform the functions of switching on the signal format converter CP29 and the switch and trunk functions, to connect one or more of the telephone functions, and to look for a free outgoing sub-connection to the next node in the connection and establish it. To do this, the third controller receives a signal M5 from the first controller indicating the incoming connection and the function address of the telephone function to be switched on. The signal M5 may also contain information about a node to which a sub-connection is to be connected as a continuation of the incoming connection. The third controller BC3 outputs to the first controller CC1 a signal M6, which may include, inter alia, information about which connection is established to the next node. The signal format converter CP29 with the switch and trunk functions CP21-CP28 converts incoming signal format to a common signal format COM1 and also converts from this format to an output signal format for the established connection to the next node.

One feature of the gateway MG1 is that the telephone functions in function block F2 are unchanged and regardless of which network the gateway is connected to. New functions may be added, but the functions themselves should be unchanged with time. Another feature of the gateway is that any telecommunications network can be connected using the gateway and the corresponding new switch and trunk functions can be added significantly to the telephone functions and so on. The switchtrunk functions can be stored in the form of hardware or

522 271 software and can be stored anywhere within their respective block. The gateway can also be easily expanded for increased capacity.

The gateway MG1 utilizes that the signals on terminal C31 or C32 are connected to their respective switching and trunking functions CP21-CP27 and then converted to the common signal format COM1 in converter CP29. This then converts the signals into a signal format adapted to that of the switch and trunk functions CP21-CP27 used when the signal is to be transmitted on a sub-connection to the next node via the connection C41 or C42. Between these two conversions, one or more of the F21-F28 telephone functions can be connected via connection 1/02, if necessary for the connection. Furthermore, a fully connected, ongoing connection between the two subscribers A1 and B1 can be broken up and additional one or more telephone functions can be added. Examples of such functions that are added are the conference function F28 to connect additional subscribers to the connection or the function F25 with standard messages. All the phone functions work on the common signal format COM1, which is the format the signals have on the connection 1/02. When a connection is connected via the MG1 gateway, it may happen that none of the telephone functions in function block F2 need to be switched on. However, the transmitted signals have different formats at the input and at the output and the incoming signal is converted, as mentioned above, to the common signal format in converter CP29 to be converted again to the output signal format.

The gateway MG1, and also the gateway MG2, are constructed from a logical point of view as described in connection with Figure 2 with the three separate, cooperating controllers CC1, RC2 and BC3. This structure allows the gateway to have the above-mentioned properties. The common signal format COM1 can be a format known in the art and this is the case in

522 271 of the present embodiment. Here, the format AAL2 is used, which stands for ATM Adaption Layer type 2, where ATM in turn stands for Asynchronous Transfer Mode. In connection with Figures 3, 4, 5 and 6, with some embodiments, it will be explained how the gateway MG1 or MG2 works.

Connection of a connection from subscriber A1 to gateway MG1

In connection with Figure 1, it was initially mentioned that the two subscribers A1 and B1 are connected to each other so that they can talk. A first part of this connection is a call request from the subscriber A1 and connection of the connection to the gateway MG1 with a signal converter and switching on at least one of the telephone functions. Figure 3 shows a flow chart of this first part of the connection.

The subscriber A1 conventionally dials, on his mobile MP1, the telephone number of the subscriber B1's telephone POT1 according to block 41 and is connected via the base station BS1 to the gateway MG1 over the connection C31 according to block 42. The signaling from the subscriber A1 is switched over the connection C1 to the control server SI, block 43 This server detects which signal format the subscriber A1 has, in this case, compressed speech, and also senses that the network N1 is an ATM network, all according to block 44.

When calling from subscriber A1, the server receives some information about subscriber B1, so that the server can determine the node address of the next node that must be connected. The server SI thus has the information needed to connect the subscribers A1 and B1. The server sends, over the connection C1, control signals in the form of the message M1 to the gateway MG1 and more specifically to the signal processing unit CP1 according to block 45. The message M1 is a standard protocol with an address header and an information section divided into different

522 271 data packets. The signal processing unit CP1 separates the address head and sends the information part of the control signals with the message M2 to the first control unit CC1 according to block 46. This information part is analyzed by the first control unit, inter alia with regard to information on which telephone functions are required and on information on signal format and a network address ADR2 for the connection. from subscriber A1, all according to block 47. The first controller CC1 sends a request to the second controller RC2 with the message M3 on one of the telephone functions, block 48. The mobile phone MP1 of the subscriber A1 sends coded speech, which must be decoded in order to be perceived with the telephone apparatus POT1 of the subscriber B1. The message M3 thus contains a request for the telephone function F21 with a coding / decoding function. The second controller RC2 seeks a vacancy of these functions according to block 49 and sends its functional address ADR11 with the message M4 to the first controller CC1 according to block 50. The first controller now sends, with the message M5, the functional address ADR11 for the vacant function F21 and the network address ADR2 for the incoming connection to the third controller BC3 according to block 51. With the message M5, the first controller also sends a request for the third controller to associate the network address ADR2 with the address ADR11 for the selected free encoding / decoding function F21 according to block 52. The third controller BC3, according to block 53, switches on the switching address. and the trunk functions corresponding to the network address ADR2, in this example the CP23 function for ATM switching. The function CP23 is paired with the telephone function F21 according to block 54. Thus, a voice signal TS1, which subsequently enters the terminal C31 from the subscriber A1, can be received by the switch function CP23 and transformed into the common signal format COM1 in the signal format converter CP29. The voice signal TS1 can then be decoded via the telephone function F21, which works on it

522 271 common signal format, before switching this speech signal on.

Connection of additional telephone function in the gateway MG1

In the example above, only one of the telephone functions, the coding / decoding function F21 is switched on. Often, several telephone functions must be connected and this is the case here as well. The subscriber B1 has the telephone POT1 which must have a ringtone and in addition there may be echoes in the connection. Thus, the tone generation function F24 and the echo extinguisher F22 must be switched on.

When subscriber A1 called, a message was sent to server SI about the dialed subscriber B1. The server thus has information about the subscriber's Blond address NODI and that it requires ringing signal and echo cancellation. These data were passed on to the gateway MG1 with the message M1 and further with the message M2 and analyzed in the first controller CC1. In connection with the flow diagram in Fig. 4, it will be described how the additional telephone functions are connected to the connection.

According to block 47 in Figure 3, the first controller CC1 analyzes the message M2. This controller now requests, according to block 61, the next telephone function of the second controller RC2 with the message M3. This second telephone function is, according to the example, the telephone function F24 for tone generation. The second control unit searches for a free copy of this function according to block 62 and, according to block 63, sends the function address F24 of the function F24 with the message M4 to the first control unit CC1. This control unit transmits with the message M5 the function address F3 of the telephone function ADR3 to the third control unit BC3 according to block 64 and also sends according to block 65 a request to switch on the telephone function F24 in the connection. The third controller BC3 according to block 66 switches on this telephone function in the connection, which according to

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above is at a stage where it is already converted to the common signal format COM1. The first controller continues the analysis of the message M2 and the procedure of Figure 3 is repeated if more telephone functions are to be switched on. As is the case in this example, also the F22 echo cancellation telephone function with a function address ADR4 is switched on in the connection when it is on the common signal format COM1.

It should be noted that the switching procedure in gateway MG1 will be the same as described in the two examples above, although the incoming connection on connection C31 would come from some other node than the base station BS1 with the address NOD2. An example of such an alternate node is another gateway, for example, the gateway MG2 with a node address NOD3. Switch and trunk functions and telephone functions may need to be selected differently, but the switching process itself is unchanged.

Connection from the gateway MG1 to the subscriber Bl

As mentioned above, the server has information about the dialed subscriber B1 and can thereby determine the next node to which the connection from the subscriber A1 is to be connected. The next node could, by way of example, be the next gateway MG2, but according to the present embodiment, the switch is VX1 with the node address NODI, to which the subscriber B1 is connected. How the connection from subscriber A1 is connected further with a sub-connection to switch VX1 is described below in connection with figure 5.

The server SI states that the switch VX1 has the node address NODI and sends it with the message M1 to the signal processing unit CP1. This in turn sends the node address NODI to the first controller CC1 with the message M2 according to a block 71. The first controller sends, with the message M5, the node address NODI to the third controller BC3 together with a request to look up a

522 271 free connection to the node, all according to a block 72. The third controller BC3 seeks a free connection, for example the connection C41, and establishes it according to a block 73. The third controller sends a message M6 with information on the established connection C41 to the first controller CC1, block 74. According to block 75, the first controller sends message to the third controller BC3 to enable it by the switch and trunk functions corresponding to the established connection C41. The third controller seeks out the function CP21 for IProuting with an address ADR21 and switches this function on to the last connected telephone function in the connection according to block 76. The signal format converter CP29 converts the common signal format COM1 to a signal format for the established IP connection according to block 77. The switch VX1 is now connected and generates a signal from the telephone function F24 a ring signal to the telephone POT1 according to block 78. The subscriber B1 receives the call telephone handset, block 79.

Connection of connection via another gateway

In connection with a flow chart in Fig. 6, connection of a connection between the first subscriber A1 and the third subscriber B2 in the network N3 will be described briefly. At the first part of the connection from subscriber A1 to gateway MG1, only the switch and trunk function CP23 for ATM switching is switched on and the connection is converted to the common signal format COM1. This first step is indicated by block 81. Gateway MG1 then switches the connection to gateway MG2 via the network N2 according to block 82. This connection is carried out in a similar way to the connection to the subscriber B1 as described in Figure 5. The difference is that none of the telephone functions are switched on in the gateway MG1 and that the server SI orders connection to the node address NOD3 instead of the node address NODI. Another vacant IP connection is also sought and established by the third

522 271 control unit BC3. Function CP21, which corresponds to the connection, is switched on and a conversion of the signal format to the connection's IP format is performed. The connection is then received in the gateway MG2 according to block 83. The connection is then converted from the IP format to the signal format COM1 and the three telephone functions F21, F22 and F24 are switched on. It should be noted that this connection of the telephone functions is only done now in gateway MG2. The connection is further connected to switch VX2 with the node address NOD4, according to block 84, in a similar manner as described in connection with figure 5. The connection is hereby converted to STM format and the switching and trunking function CP26 is switched on. The reciprocal link is then switched from subscriber B2 to gateway MG2 according to block 85, whereby the F21 encoding / decoding function is switched on to the common signal format COM1 after the conversion from the STM format. A free connection to gateway MG1 with a node address NOD5 is sought by the third controller in gateway MG2 and switch function CP21 is switched on for conversion to the IP format, all according to block 86. In gateway MG1, according to block 87, a conversion of the signal format from the IP format to the common signal format COM1 is performed. . A free connection to the base station BS1 is sought and established by the third controller BC3, the switch and trunk function CP23 is switched on and the signal format is again converted to ATM format, block 88. The switches in the example above performed in the respective gateway are shown in more detail in the previous embodiment. .

It should be noted that in the examples, the various functions F21-F28 and CP21-CP27 have been retrieved within the gateway that is just about to disconnect. However, it is possible for a gateway to retrieve an edition of one function from another gateway if all its own editions of that function are occupied. For example, the gateway MG1 can retrieve the F21 coding / decoding function of the gateway MG2 when

522 The 271 gateway MG1 connects the connection between subscribers A1 and B1 according to block 49 of Figure 3.

In the description above, an example of the MG1 logical structure of the gateway has been given. Some examples of connecting connections in this gateway have also been described. It can be seen that this connection requires many steps and in most cases interconnection of one function device with each other for the telephone functions and the switch and trunk functions. This interconnection can be made efficient and resource saving. It is important, therefore, that the functional devices interconnected in a gateway are close to one another in the sense that only small resources are needed to utilize the functions together. The purely physical structure of the gateway is thus essential. It is also important to be able to easily find these functional devices in the gateway when they are to be connected to the connection.

in the majority of connecting like that

In conjunction with Figures 7A, 7B and 7C, the hardware structure of the gateway MG1 will be described in a clear way, ie the carriers supporting the gateways functional devices shall be described. Figure 7A shows the structure of the hardware in a magazine. This has a backplane 101, to which various circuit boards are connected. Examples of the circuit boards may be mentioned a switch board 102 (SCB Switch Core Board), a main board 103 with the main processor (GPB General Purpose Board) or card 104 with the aforementioned telephone functions F21-F28. The cards are, as usual, according to Figure 7B, inserted into a magazine SR1, the back of which contains the backplane 101. The gateway MG1 is made up of one or more magazines, according to the example magazines SRI, SR2, SR3 and SR4, which are assembled into a unit according to Figure 7C and whose different backplane are connected to each other.

Figure 8 shows an example of how the functional devices for the telephone functions and the switch and trunk functions are

522 271 arranged on the circuit boards in the magazine SR1-SR4. A CBET1 circuit board for switching and trunk functions carries the CP21 function for IP routing and a circuit board CBET23 carries the CP23 function for ATM switching. These two circuit boards are located in the magazine SR1. The figure also shows in some more detail how the function CP23 is connected to the connection C31 and the function CP21 is connected to the connection C41. In the same magazine SR1, circuit boards CB1 ... CB9 are placed. The circuit board CB1 carries functional devices with a number of editions of the encoder / decoder F21 in Figure 2 and the circuit board CB9 carries functional devices with a number of editions of the echo extinguisher function F22. The circuit boards are interconnected by a packet selector PS1, which is shown by a solid line 105 between the circuit boards and the packet selector. The figure also shows some of the circuit boards in more detail. The circuit board CB1 is shown with five signal processors DSP11DSP15 with connections 106. The DSP11 signal processor is shown with four access points SAP11 - SAP14. One or more editions of a telephone function, in the example encoder / decoder F21, are accessible via one of these access points, for example the access point SAP13. The circuit board CB9 has four signal processors DSP91-DSP94, the signal processor DSP91 has four access points SAP91-SAP94 and a number of editions of the eco-extinguisher F22 can be reached via the access point SAP92. Signal processors with access points are not displayed on the CBET1 or CBET3 circuit boards.

The distribution of the telephone functions described in Figure 8 is referred to as distributed distribution, since each circuit board carries only one type of telephone function. Correspondingly, there is an integrated distribution shown in Figure 9. As above, the switch and trunk functions are arranged on the circuit boards in the magazine SR1, where the circuit board CBET1 carries the function CP21 and the circuit board CBET3 supports the function CP23. In the magazine SR2, circuit boards CB10-CB19 are placed. The circuit board CB10 carries, as does the circuit board CB 19,

522 271 a number of editions of the encoder / decoder F21 together with the echo extinguisher function F22. The circuit boards carry signal processors, of which processor DSP101 is displayed, and these have access points, of which access point SAP101 is displayed. The circuit boards are connected to each other via the packet selector PS1.

The above-described distributions of the functions on the circuit boards can be performed as a static distribution so that a particular circuit board always has a certain number of editions of one of the functions. The integrated distribution can also be performed as a dynamic distribution. In this case, the number of editions of one of the telephone functions on a circuit board may vary and this number is determined by the need that exists. This is possible because the PCBs can have standard processors, with code in their memory for several different phone functions. Resource management becomes more complicated and the controllers have to manage the resources from several circuit boards as a pole of telephone functions. The controllers have a list of available and busy resources and the list is not linked to any specific of the telephone functions.

As mentioned above, it is essential that the interconnection of the various functional devices is carried out in a resource-saving manner. In this connection, it is essential to limit the utilization of the communication resources required to interconnect the functional devices. When two consecutive of these functional devices are located within the same gateway, the gateway's internal communication resources are utilized. The operating devices are switched on in the connection in sequential order as exemplified in Figure 10. According to block 91, switch and trunk function CP23 are first connected, then telephone function F21 according to block 92, after which, according to block 93, telephone function F22 is connected and finally according to block 94 switch and trunk function CP21. Details of similar couplings have been described in connection with Figures 3, 4 and 5. The two blocks 92 and 93 engage the consecutive functional devices for

522 271 telephone functions F21 and F22. To make this connection resource-saving and fast, units are selected in the gateway according to the following priority list, where the first choice is according to point 1, the second choice according to point 2, etc.:

1st The functional devices are reached via the same access point.

2nd The function devices are handled by the same signal processor.

3rd The function devices are handled by signal processors on the same circuit board.

4th The circuit boards are in the same tray.

In cases where a gateway is allowed to retrieve functions from another gateway in the telecommunications network TS, the following steps are added in the priority list:

5th The magazines belong to the same gateway.

When one of the switch and trunk functions and one of the telephone functions is to be selected one after the other, for example according to blocks 91 and 92 or according to blocks 93 and 94, the following priority list is used:

1st The functional devices belong to the same magazine.

2nd The functional devices belong to the same gateway.

This latter priority list can, of course, be extended to include, for example, an attempt to select a common circuit board as the first step.

In connection with Figures 3, 4, 5 and various functional devices CP21-CP27 addresses, for example, the addresses ADR21 controllers CC1, RC2 interconnect the functions were more specifically mentioned that they and F21-F28 have and ADR3, which and BC3 are used to connect. The addresses to be able to find the different functional devices and be able to choose according to them

522 271 predetermined priority lists above. The addresses of the functional devices are therefore hierarchically arranged as will be described in connection with Figures 11 and 12. Figure 11 shows a block diagram with a structure for an address 110 of the telephone functions F21 - F28. A block 111 indicates in which node the function is stored, for example in gateway MG1. A block 112 indicates one of the trays in this node, for example, the magazine SR1, a block 113 indicates one of the circuit boards in this magazine, for example, the card CB1, a block 114 indicates one of the processors on this card, for example the processor DSP11, and a block 115 indicates one of the access points e.g. access point SAP11. The addresses of the telephone functions, for example the addresses ADR3 and ADR11, have this structure. Figure 12 shows a block diagram with a structure for an address

120 for the switch and trunk functions CP21-CP27. One block

121 indicates in which node the function is stored, for example, gateway MGW1, a block 122 indicates one of the trays, for example, the magazine SR1, and a block 123 indicates one of the circuit boards in this magazine, for example, the circuit board CBET3. In addition to the location of the functions, the address also indicates, through a block 124, one of the connections that may exist to the functional device in question and through a block 125 a user is indicated on this link. The previously used address ADR21 has this structure.

In connection with Figures 3-6, it has been explained how the addresses are used to establish a connection. In connection with Figures 13, 14 and 15, it will be explained in more detail how the hierarchical structure of the addresses according to Figures 11 and 12 is utilized to connect the functional devices according to the above priority lists.

Figure 13 is based on a case when one of the telephone functions is to be switched on in the connection, for example when an edition of the telephone function F22 according to block 93 in Figure 10 is switched on. The process starts with the second controller RC2 in a step 130 receiving a request from the first controller CC1 to

522 271 turn on the function previous address in the phone function examines in

F22,

This request contains

that is, the address of the second controller about the access point of response Y1, the address of the chain is obtained;

F21 in block 92 a step 131 the telephone function F21, block 115 in Figure 11, can be utilized. The controller then investigates whether any edition of the telephone function F22 is available from this access point and whether sufficient processor capacity to handle the function is also available. If an affirmative, the processor capacity is reserved and the access point is delivered to the first controller CC1 in a block 136. If the answer is denying N1, the second controller RC2, in block 132, similarly examines whether the signal processor has an edition of the telephone function F21, block 114 in Figure 11, which may be utilized. In the affirmative answer Y2, processor capacity is similarly reserved and the address, now with another access point, is delivered to the first controller, block 136. In denial response N2, the procedure is repeated in a block 133 with an examination of whether an edition of the telephone function F22 is available on the circuit board, block 113 in Figure 11, and if necessary processor capacity is available. In the affirmative answer Y3, capacity is reserved and the address is delivered, this time with an access point from another processor. In the case of denial response N3, the procedure is repeated again according to a block 134, the second control unit examining whether the magazine for the telephone function F21 has an edition of the telephone function's address according to block 112, and is there. In the event of an affirmative response Y4, as before, the address according to block 136 is delivered to the first controller and the processor capacity is reserved. The address delivered this time is the address of an access point for a processor on a circuit board in the magazine that carries the F21 function. In the event of a negative response N4, the second controller finally checks whether in the entire node, with the address 111, there is an available edition of the function F22 and available, with processor capacity

F22 om

522 271 sufficient processor capacity. In the case of a yes response Y5, as described above, the address of a found access point is delivered to the node of the block 136. If a negative response N5 is obtained, the request of the first controller of the telephone function F22 according to a block 137. The method has thus resulted in either an address according to block 136 or a rejection according to block 137 and a new request can be processed according to block 138.

As an alternative to the rejection in block 137, another node in the network can be searched, which may have an edition of the requested function available. The address of its access point, including the node's address, is provided to the controller concerned.

An alternative to the method of Figure 13 will be briefly described in connection with the flowchart of Figure 14. The process begins with the request for the telephone function F22 from the first controller CC1 to the second controller RC2 in a block 140. The second controller investigates according to block 141 on the requested function F22 is located in the same node as the previous telephone function F21. In the case of a negative response N6, the request according to block 147 is rejected. If a yes response Y6 is investigated, if the function is in the same magazine according to block 142. If a negative response N7 is obtained, the address found at the previous step 141 is supplied and the required processor capacity is reserved, as indicated by a block 146. In a yes response Y7 is tested according to block 143 if the function is on the same circuit board. In the case of a negative response N8, the address is delivered from the previous step; in the case of a yes response Y8, according to block 144, the function is found on the same processor. A negative response N9 causes the address from the previous step 143 to be delivered. An affirmative answer Y9 entails an investigation according to a block 145 of whether an edition of the requested telephone function F22 is located at the same access point as the previous telephone function F21. In a negative answer NIO

522 271, the address found in the previous step is delivered, and in the case of a yes answer Y10, the address just found is delivered and processor capacity is reserved, see block 146. A new request can be processed according to block 148. In case the telephone function can be retrieved from another node, the procedure starts with a corresponding request.

In connection with Figure 15, an example of how the priority list is utilized to find an appropriately placed edition of the switch and trunk function CP21 in Figure 10 will be described, which has a hierarchical address with a structure shown in Figure 12. In this case it is the third controller BC3 which receives a request from the first controller CC1 for an address of the requested function. This should be as close as possible to the previous function, ie the telephone function F22. The procedure begins with the request of the third controller in a block 150. In a block 151, the third controller BC3 examines if there is any available edition of the function CP21 in the same node as the telephone function F22 is located and if the required processor capacity is available. In a negative answer Nil, the request is rejected according to block 157. In the affirmative answer Yll, the controller BC3 investigates according to a block 152 if there is any available edition of the function CP21 in the same magazine as the telephone function. In a negative response N12, the third controller BC3, according to block 156, delivers the address for the edition of the function CP21 found in block 151. Receivers are, as before, the first controller CC1. In the affirmative answer Y12, the third controller according to a block 153 examines if there is an edition of the function CP21 on the same circuit board which carries the telephone function F22. In the case of a negative response N13, the third control unit BC3 delivers the address of the edition found according to block 152. In a yes response Y13, the address found according to block 153 is supplied with the address of the first oxygen unit CC1 together with information on

522 271 reserved processor capacity, block 156. According to block 158, a new request can be handled.

In connection with Figure 2, the gateway MG1 was described, which was used as an example of a switching node which may have hierarchically constructed carriers. It should be noted that the switching node may be designed differently. An example of such a configuration is that the converter CP29 in Figure 2 is designed as one of the telephone functions in function block F2. Another example of the design of the switching node is that all the functions, both the telephone functions F21-F28 switch and trunk functions CP21-CP27, are unit and controlled from a single central control unit. This provides a somewhat simpler but less flexible structure of the switching node.

which gathered in one

The above has been described how the telephone functions as well as the switch and trunk functions are selected for a connection. It has also been shown how a suitable candidate among the processors is chosen to handle the functions. It is important that the total processor capacity of a node is utilized efficiently. The choice of processor candidate is therefore carried out in a flexible manner, after which it is checked whether the selected candidate has sufficient capacity in various respects. If the candidate's capacity is insufficient, a new candidate is appointed who is in turn checked. This will be described in more detail below.

In connection with Figure 8 and Figure 9, the circuit boards CB1CB9 and CB10-CB19 have been described, each of which can handle several of the functions F21-F28 simultaneously. Each circuit board has several processors, such as the DSP91-DSP94 processors, and each processor can handle several of the telephone functions. The total processor capacity from all the circuit boards in, for example, the node MG1 can be used effectively if this processor capacity is utilized as a common, flexible resource in the node. Therefore, a circuit board in the node cannot have a fixed number of editions of a particular telephone function stored.

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The distribution of the telephone functions on some circuit boards and their processors can also not be unchanged. It is not possible to know in advance how many editions of each of the telephone functions needed in the node and the need may vary with time. Therefore, the processors are not generally pre-loaded with computer code for the telephone functions, but the processors are instead usually managed as common resources in the following way.

1st The instruction memory in each processor is managed as a resource, since each processor can handle that number of phone functions but in most cases not all of them. A processor that would handle all the phone functions would need a large instructional memory, which is expensive and takes up a lot of space on the circuit board.

2nd The processor capacity, expressed in, for example, MIPS (mega instructions per second) for each processor, is managed as a resource. This allows the capacity to be fully utilized and at the same time avoids that the available capacity is exceeded.

3rd The data memory for each processor is managed as a resource in order to fully utilize this memory while avoiding exceeding available memory capacity.

Both the distribution of the data code for the telephone functions and the number of editions of each telephone function in the node depend on the need that exists at a particular time. A method of distributing the telephone functions so that the total processor capacity of the node is utilized will be described below in connection with the flowchart of Figure 16.

When the first controller CC1 is to assign one of the telephone functions F21-F28 to the connection, it sends a request thereto to the second controller RC2 as previously described. This request is the starting point of the procedure according to a step 160. The computer code for the telephone function may be

522 271 stored on, for example, one of the circuit boards CB1-CB9, but also alternatively in a central processor in the node MG1 or in another node in the telecommunication system TS. According to a step 161, the second controller RC2 selects one of the processors, for example according to the previously described priority list with points 1-5. The second controller, according to a step 162, controls, on the one hand, the amount of processor capacity available in the selected processor and, on the other, the amount of processor capacity required to process the current telephone function. Then, the controller compares whether the processor capacity is sufficient according to a step 163. If the response is negative according to an alternative NO, the second controller RC2 selects a new processor in step 161. If the answer is positive according to an alternative YES, the second controller controls both the amount of data memory needed for the current telephone function and the amount of memory capacity the processor can provide, all according to a step 164. According to a step 165, the second controller RC2 then compares the available memory capacity is sufficient. If the response is negative according to an alternative NO, the controller selects a new processor according to step 161. If the answer is positive according to an alternative YES, the second controller checks in a step 166 whether the data code for the current telephone function is available on the processor. If this is not the case according to an alternative NO, the second controller RC2 checks according to a step 169 if the data code fits into the instruction memory. If the answer to this question is negative according to an alternative NO, a new processor is selected in step 161. If the answer is yes according to an alternative YES, the processor capacity, the data memory and the instruction memory are booked in a step 170. Then the data code according to a step 171 is loaded and the assignment of the telephone function to the connection is completed according to a step 168. In step 166, the second controller examined the data code for the current code. the phone feature was available on the processor. If this is the case according to an alternative YES, the second controller RC2 books the processor capacity and

522 271 data memory according to a step 167. The assignment of the telephone function to the connection is thus completed according to step 168.

In order to carry out the procedure described above, the second controller RC2 has access to the following information, which inter alia relates to the processors on the various circuit boards.

1st The hierarchical address of the processors.

2nd What phone functions the various circuit boards can provide.

3rd How much free processor capacity the different processors can provide.

4th How much data memory is available for the different processors.

5th How much instructional memory is available for the different processors.

6th How much processor capacity is required for the different telephone functions.

7th How much data memory is required for the various telephone functions.

Eighth How much instructional memory is required for the various telephone functions.

In connection with Figure 9, the circuit boards CB10 and CB19 have been described. These circuit boards carry the encoder / decoder F21 together with the echo cancellation function F22. According to an alternative to the method of Figure 16, not only one telephone function is handled at a time when a processor is to be trained which has sufficient capacity. Instead, at least two of the telephone functions are handled together, for example functions F21 and F22. These two functions can be expected to be utilized

522 271 for long call connections. If the two functions are executed together, less processor capacity is required than if they are executed separately.

According to a further alternative, the capacity of the requested processor is compared with threshold values ​​instead of being compared with the required capacity for the function in question. The thresholds are set so that if the processor capacity reaches the thresholds, this capacity is sufficient for each of the functions.

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