WO2002037813A1

WO2002037813A1 - System and method for announcing messages to phone users in a telecommunications network

Info

Publication number: WO2002037813A1
Application number: PCT/SE2001/002304
Authority: WO
Inventors: Peter Larsson; Patrik Wiss; Ulf Ekstedt; Lars-Göran Petersen
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2000-10-31
Filing date: 2001-10-19
Publication date: 2002-05-10
Also published as: AU2001296181A1

Abstract

A message announcement system and/or method is provided in a client(s)-server structure. A plurality of messages, or messages portions, are stored in a memory of an announcement/message server, which in preferred embodiments may be a shared resource in a node of the network. The server is capable of serving multiple announcement/message clients. Appropriate messages are distributed from the server to various announcement clients throughout the system. An exemplary message may be, for example, 'The number 123 456 7890 has been disconnected' or 'The number you are trying to reach xxx yyy zzz, is out of service'. Message stream handling/processing may be handled in an asynchronous manner between the server and client(s). However, the system may be adapted and/or interconnected with synchronous systems via at least one interface (I/F).

Description

SYSTEM AND METHOD FOR ANNOUNCING MESSAGES TO PHONE USERS IN A TELECOMMUNICATIONS NETWORK

This invention relates to a system for announcing messages to telephone users in a telecommunications network (e.g., in a cellular telecommunications network or any other type of suitable network).

BACKGROUND AND SUMMARY OF THE INVENTION

Systems for announcing messages to telephone users in telecommunication systems are known in the art. "Messages" can be either standard messages or concatenated messages made up from several submessages joined together. Message announcements may be utilized in conjunction with DTMF receivers in voice prompting applications, or in other suitable applications.

For message announcement systems used in telecommunications networks, PCM coded speech messages are often used and are typically stored on hard disks. Because a large number of such messages typically has to be stored, combined with required access times of hard disks and cost-related factors regarding the same, efficient distribution of such messages to end users is often lacking.

Accordingly, it will be apparent to those skilled in the art that there exists a need for a system and corresponding method for enabling messages to be efficiently announced and/or distributed to end users (e.g., mobile phone users, fixed phone users, pager users, etc.) of a telecommunications network.

According to this invention, a message announcement system and/or method is provided in a client(s)-server structure. A plurality of messages, or message portions, are stored in a memory of an announcement/message server, which in preferred embodiments may be a shared resource in a node of the network. The server is capable of serving multiple announcement/message clients. Appropriate messages are distributed from the server to various announcement clients throughout the system. An exemplary message may be, for example, "The number 123 4567890 has been disconnected" or "The number you are trying to reach xxx yyy zzzz, is out of service." Each announcement client preferably includes a certain amount of memory for buffering messages or message portions received from the announcement server, so that the client can send complete messages or portions of messages to end users (i.e., phone users) in the desired format (e.g., PCM (Pulse Code Modulation) voice) and/or at an appropriate rate (e.g., in approximately real time in an asynchronous system). In certain embodiments, announcement clients are capable of converting a message or message portion received from the announcement server in a first format (e.g., text, voice, video clips, pictures, or any combination thereof) into a second format such as a synthetic voice format to be thereafter distributed to appropriate user(s). Switch(es) and interface(s) are provided so that respective clients may distribute messages to different end users throughout the network.

In certain embodiments of this invention, the announcement server along with a plurality of announcement clients may be provided at a single node of a network. Alternatively, in other embodiments of this invention, certain announcement clients may be provided at different nodes of the network than the node at which the announcement server(s) is located.

Optionally, certain interfaces (I/F) between the switch (e.g., ATM switch or IP router) and eventual end users may include sufficient memory for enabling the message distribution system/method herein to be asynchronous in nature up until the interface(s) and synchronous thereafter. Thus, message streams sent from the announcement server can be processed in an asynchronous manner by the client(s) and/or switch(es), and can be connected to a synchronous system (e.g., an exchange in the PSTN) via the interface(es) (I/F) which is/are provided at the edge of the message distribution system of this invention.

Certain advantages will be apparent to those skilled in the art as a result of the instant invention. For example, in certain embodiments announcement clients may be implemented together with other speech processing devices on speech processing boards where hard disks typically are not provided. The announcement server(s) with hard disk memory can be placed anywhere in the network. Accordingly, the actual place where a message is executed (e.g., at the client location) can be moved closer to the eventual receiving end user so as to reduce costs, reduce the potential for delay, and/or provide more efficient message distribution. Additionally, because all messages and/or message portions need only be stored at a centrally located server location(s), seldom or infrequently used messages (e.g., messages in seldom used languages) can be stored at the server location and need not take up valuable storage space at other locations (e.g., client locations) throughout the network.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects, features, and advantages of this invention will be apparent from the following more particular description of preferred embodiments as illustrated in the accompanying drawings in which reference characters refer to the same parts throughout the various views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating certain principles of the invention.

Figure 1 is a schematic/block diagram of a first embodiment of this invention.

Figure 2 is a schematic/block diagram of an embodiment of this invention similar to that shown in Figure 1, except that asynchronous as well as synchronous domains are illustrated in the message distribution system of the invention.

Figure 3 is a diagram of an exemplary network in which the instant invention of either Figure 1 or Figure 2 may be implemented.

Figure 4 is a schematic functional diagram of the UTRAN of Figure 3.

Figure 5 is a schematic functional diagram of an MGW (media gateway) node of Figure 3 at which an announcement server and several announcement clients of the instant invention may be located. Figure 6 is a functional block diagram of the MSB processing board of Figure 5.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

OF THIS INVENTION

In the following description, for purposes of explanation and not limitation, 5 specific details are set forth such as particular architectures, interfaces, protocols, techniques, etc. in order to provide a thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of devices, circuits, protocols, and methods are omitted [0 so as to not obscure the description of the present invention with unnecessary detail.

Figure 1 is functional diagram of an embodiment of this invention. An exemplary use of this invention is to send a message to an end user or subscriber on the PSTN (Public Switched Telephone Network) if a particular mobile station (MS) which the end user is attempting to contact or reach is out of service or cannot be reached.

15 Alternatively, this invention may be utilized to send a message to a mobile phone user if another phone (fixed or mobile) or pager the user is attempting to reach is out of service or disconnected. An exemplary message in this regard could be "The user cannot be reached", or "The number xxx yyy zzzz is out of service", or "The number xxx yyy zzzz has been disconnected, the new number is aaa bbb cccc." Other suitable

,0 messages may also be sent.

Alternatively, messages according to this invention may be sent in the context of any suitable intelligent network service (i.e., the invention is not limited to a cellular telecommunications network). For example, if a user (i.e., either a fixed telephone user on the PSTN, or an MS user) attempts to purchase a train or bus ticket, the system of 25 this invention may send appropriate messages regarding the same to the user upon implementation of DTMF prompts. Thus, it can be seen that the instant invention may be used in the context of a mobile or cellular telecommunications network, or alternatively in the context of other suitable intelligent network applications. The message announcement system 1 illustrated in Figure 1 includes processing board 3, announcement/message server 7, server memory 5 (e.g., hard disk), non-realtime transport 9 such at the Internet or any other suitable packet or cell switched network, a plurality of message or announcement clients 11 operatively associated with one or more digital signal processors (DSPs) 13, switch 15 (e.g., ATM switch, real-time router, etc.), and interfaces (I/F) 17 for enabling messages to be sent from clients 11 to respective telephone users 19. For example, one or more of the following interfaces (I/F) 17 may be provided: IP interface, ATM interface, TDM interface, Ethernet interface. Messages may thus be delivered to end users 19 via various protocols and/or networks. Connection handler 16 preferably controls the connection chain so that the client need not request the server to send speech packets (i.e., the connection handler can do the requesting).

Announcement server 7 and memory 5 are preferably located on processing board 3 at a node of the network. Memory 5 functions to store a plurality of messages and/or message portions that are retrievable by server 7. Server 7 and/or memory 5 is/are preferably a shared resource(s) in the node or network where it is located (i.e., server 7 functions in the context of the instant messaging invention, as well as for performing other server-related duties/tasks).

Messages and/or message portions retrieved from memory 5 by server 7 are downloaded to respective clients 11 via transport layer 9. Transport layer 9 may be, for example, a non-real-time (nrt) transport protocol (e.g., TCP/IP, ATM/AAL5, etc.) so that communications between server 7 and respective clients 11 are handled in a non- real-time manner. Announcement/message clients 11 are preferably operatively associated with corresponding processors 13. In preferred embodiments, clients 11 are simple in form and comprise a small amount of memory 10 (e.g., a few seconds of speech memory). Clients 11 buffer messages and/or message portions received from server 7, and send the resulting messages to appropriate end user(s) 19 in the expected or desired format (e.g., voice/speech format) and/or at the appropriate rate. In order to retrieve a particular message from server 7, the connection handler first makes an appropriate request for such a message. Thereafter, server 7 retrieves at least a portion of the desired message from memory 5 (preferably the entire message). Server 7 forwards a first portion of the message to a memory/buffer 10 of the client 11. The client 11 then begins to transmit or forward the first message portion to the appropriate user 19 via switch 15 and interface 17. As the content of the client's memory 10 is reduced to a particular threshold as the first message portion is being played out, the client 11 sends another request to server 7 for an additional portion(s) of the message. For purposes of example only, this may be carried out in a TCP/IP system by the protocol. In response, the server 7 forwards a second portion of the message to the client 11 via transport layer 9. This process continues until the entire message has been received by the client 11 from the server, and played out to the appropriate end user(s). In other words, clients 11 send continuous requests to server 7 as message portions in their memories 10 are output in the appropriate format, until a client has received the entire message from the server that it desires to play out. Such requests from the client are sent to the server "just in time" when client memories or speech buffers 10 are reduced to a certain threshold. Memory 10 at each client preferably has a capacity less than that needed to store entireties of certain messages to be played out to end users. In such a manner, clients 11 can output complete messages to users 19 in an expected format and/or at an appropriate rate (e.g., approximately real time) while only utilizing a small amount of memory which may or may not be capable of storing an entire message. In certain embodiments, the client is also capable of connecting the message or message portion to another format.

For example, consider a situation where a client 11 desires to send the following message to a user 19 of a mobile phone: "Sorry, the mobile phone which you are attempting to reach is out of service." The connection handler sends a request to server 7 requesting the identified message. Server 7 retrieves at least a portion of this message from memory 5, and initially sends the following first portion of the message to the client: "Sorry, the mobile phone which you are attempting to reach". This initial message portion is received by the client 11 and stored in its memory 10. The client then begins to play out this initial portion of the message in approximately real time, via switch 15 and an interface 17 to an end user 19. While playing out this initial message portion, the client's memory 10 content is reduced below a particular threshold at which time the client sends another request to the server 7 asking for the remaining portion(s)

5 (or the next portion) of the message. In response, server 7 then sends the following second portion of the message to the client 11 : "is out of service". Client 11 receives this second portion of the message before the initial portion of the message has been entirely played out to the user (if not received, the client 11 may send out silence). The second portion of the message is stored in the client's memory/buffer 10 and played out

LO immediately following the first portion so that the entire message is sent (i.e., clocked out) to the user 19 in approximately real time. As can be seen, this enables client 11 to send a message to an appropriate end user 19, wherein the message requires more memory space than the client 11 has available or desires to use.

Several advantages will become apparent to the skilled artisan upon review of

L5 the instant invention. First, it is noted that clients 11 can be implemented together with other speech processing devices on generic speech processing boards where hard disks normally are not provided (e.g., exemplary "other speech processing devices" include speech coder, echo canceler, circuit switched data application(s) providing modem functionality towards PSTN and/or ISDN, tone sending/receiving, and/or DTMF

.0 sender/receiver). This enables connection handler(s) to potentially utilize such speech processing devices in an efficient manner in order to help implement certain aspects of this invention (e.g., messages to be sent out to end users 19 may be determined by clients 11 in response to received DTMF tones initiated by end users). Moreover, the instant invention enables announcement/message server 7 to be placed anywhere in the

25 network (i.e., close to or distant from respective clients 11.) Accordingly, non-realtime communications between server 7 and clients 11 can be of the low quality of service (QoS) type, with higher quality of service communications (e.g., real-time message distribution) being carried out only from clients 11 or interfaces to respective users 19. Here, clients 11 can be positioned closer to users 19, so that much of the

50 message distribution processing need not be conducted in real time. Still further, seldom used messages (e.g., messages in rarely used languages) can be stored in memory 5 at a centralized location remote from many clients 11. This enables the instant message announcement system to not take up valuable memory space throughout the network at different client locations with messages that are rarely used. 5 Also, updates and/or changes of messages is less complex since only one centralized server is involved. Additionally, messages processing/distribution may be carried out in an asynchronous manner at least between the server 7 and client(s) 11 thereby enabling the instant messaging system to be more efficiently and/or cheaply implemented.

0 In certain embodiments of this invention, server 7 may be located at the same node as one or more clients 11. However, in alternative embodiments of this invention, server 7 may be located at a node different from a node at which one or more clients 11 is/are located. Such alternative embodiments of this invention enable messages and/or message portions to be stored at a centralized location where they are accessible and

5 may be played out by different clients at different nodes throughout the network.

Communications between server 7 and respective clients 11 are preferably in non-real-time (nrt) and asynchronous in nature. However, outside of the system (e.g., see components 3, 5, 7, 11, 13, 15, 17) or at the edge of the system there may be a synchronous system to be interconnected with (i.e., it may be desired to send messages .0 into a synchronous system in a synchronized manner). An exchange in the PSTN is an example of a synchronized system (e.g., Ericsson AXE10 exchange) to which the instant invention may be connected. In such a scenario, it is possible to adapt (or interconnect) the instant invention to the synchronous system as follows.

An exemplary method of such adaptation to a synchronous system/network may »5 comprise buffering the outgoing message stream on the interface (I F) board 17 via a memory 23, and then clocking out the message to the end user 19 in a TDM (time division multiplexed) manner. In other words, the message stream from the client 11 into the I/F memory/buffer 23 is asynchronous, and the message stream output from the memory/buffer 23 is synchronous. This is shown in Fig. 2 by dotted line 21 which differentiates between the asynchronous and synchronous domains. In such embodiments, clients 11 still buffer 10 the message portions received from server 7 in a manner so that the clients 11 can output the resulting messages in the expected format and/or rate, but synchronism is not achieved until buffering 23 at the I/F 17. This

5 enables low QoS and synchronous switching up until synchronizing buffer 23, which can be advantageous from a cost/hardware perspective. In such embodiments, buffers/memories 23 at respective I/Fs are preferably smaller than buffers/memories 10 of clients 11 (assuming that the clients 11 take care of handling the nrt issues arising from nrt transport 9). An exemplary buffer 23 is one capable of taking care of forty

10 PCM coded timeslots (40 bytes) received in an ATM cell. The I/F 17 could clock out the timeslots over a period of about 5 ms and will have received a new ATM cell from switch 15 during this time. In other words, buffer 23 in this example would be one capable of storing at least about 40 bytes, more preferably from about 50-120 bytes. Client buffers 10 may be larger than this in preferred embodiments. In still other

L5 embodiments of this invention, synchronizing buffer/memory 23 may be located at switch 15 instead of at I/F 17.

It is noted that messages may be sent in different formats from server 7 to clients 11. For example, clients 11 may receive messages and/or message portions from server 7 in the form of text, voice, pictures, video clips, SMS, or any other suitable format. 20 Clients 11 are capable of converting any received message format to a synthetic voice or speech format for playing out to respective users 19 via switch 15 and I/F(s) 17.

In certain embodiments, it is also possible to link the announcement in an existing speech chain (i.e., an active call or a call that is already set up). We can use the same resources (e.g., DSP(s)) as already used for other functions in the chain such as 25 echo canceller, DTMF sender/receiver, etc. We can use the same codec to convert the compressed speech (in one format) to uncompressed speech (in another format, e.g., PCM coded).

Figures 3-4 illustrates an exemplary telecommunications network in which certain embodiments of the instant invention may be implemented. This network includes a core network 27 having a plurality of media gateway (MGW) nodes 25 on an edge thereof, mobile switching center (MSC) server 29 in communication with at least one MGW 25, home subscriber server (HSS) 31, at least one external network (e.g., PSTN, ISDN, PLMN, Internet and/or Intranet) 33, transfer switching center (TSC)

5 server 35, SGSN server (serving GPRS (GSM packet radio system) support node) 37, and UTRAN (UMTS (Universal Mobile Telecommunications System) terrestrial radio access network) 45. As shown in Figure 4, UTRAN 45 includes a plurality of radio network controllers (RNCs) 39 which are in communication with respective radio base stations (BSs) 41. Base stations 41 communicate with mobile stations (MS) 43 (e.g.,

LO cellular telephones) via a radio interface 42 in a known manner. The communications system between MSC 29, RNCs 39, BSs 41 and MSs 43 is known in the art. For example, see U.S. Serial No. 09/095,585, the disclosure of which is hereby incorporated herein by reference.

The network architecture of Figures 3-4 divides the network into a network L5 control and a common connectivity layer. In the network control layer, the MSC server 29 controls circuit mode services and the SGSN server 37 controls packet mode services. In the connectivity layer, the MGW node 25 utilizes open interfaces 17 to connect to different types of nodes in the core network 27 and in external networks 33, 45. The illustrated H.248 protocol is the MGW control interface that enables a 20 separation of the network control and the connectivity layers, while "lu" is the interface toward the radio access network UTRAN 45 where base stations 41 and mobile stations (e.g., cell phones) 43 are located.

In the Figure 3-4 network, a voice call between (a) a mobile station 43 communicating with a base station(s) 41 of UTRAN 45, and (b) a phone user on the 25 PSTN 33, may be interconnected by the two MGWs 25 illustrated at the edge of core network 27. For example, as shown in Figure 3, the left-hand MGW 25 performs ATM (asynchronous transfer mode) switching to switch the voice system to the right MGW. The MSC 29 and GMSC/TSC server 35 control the other or right hand MGW 25. This latter MGW 25 processes the voice stream and interfaces with the PSTN 33 thereby enabling a user of a fixed phone on the PSTN to carry on a conversation with a user of a mobile station (e.g., cellular phone) 43 on UTRAN 45.

Figure 5 is a functional block diagram of an exemplary MGW 25 where an embodiment of this invention may be located. As illustrated, MGW node 25 includes switch fabric 15 to which a plurality of different interfaces 17 (e.g., ATM interface, TDM interface, IP (Internet Protocol) interface, and/or Ethernet interface), processing board 3, special purpose board (SPB) 14, and media stream board (MSB) 12 are connected. Processing board 3 at MGW node 25 may be targeted for processes that execute on a distributed processor cluster. MSB 12 is targeted for stream processing, and includes a number of digital signal processors (DSPs) 13. MSB 12 may include conventional speech circuitry such as speech coder(s), echo canceler(s), circuit switched data application(s) providing modem functionality towards PSTN and/or ISDN, a tone sender(s)/receiver(s) for providing tones to be sent to and received from end users and/or DTMF sender(s)/receiver(s).

As shown in Fig. 5, connection handler 16 is preferably located at the node of the client(s) 11, and thus need not be located at the same node as the announcement server. In certain embodiments, connection handler 16 may be located on a general processor board (GPB) at this node which is connected to switch 15. Thus, connection handler 16 may communicate with the announcement server 7 via the nrt transport using switch 15. In the Fig. 5 embodiment, it is noted that the nrt transport 9 is the same as switch 15 because the clients 11 and server 7 are at the same node. However, this need not be the case when the client(s) 11 and server 7 are at different nodes.

As can be seen in Figure 5, certain embodiments of this invention utilize boards 3 and 12, along with switch fabric 15 and different interfaces 17. For example, referring to Figures 1 and 5, announcement/message server 7 along with server memory 5 may be located on board 3. A plurality of clients 11 may be located along with respective processors 13 on board 12, so that boards 3 and 12 are operatively associated with and can communicate with one another via switch fabric (e.g., ATM switch) 15. Interfaces 17 enable clients 11 to send out messages in accordance with this invention to various end users via, for example, an ATM interface, a TDM interface, an IP interface, and/or an Ethernet interface. Thus, clients 11 may send respective messages to end users such as mobile stations 43, fixed telephone users connected to the PSTN, and/or any other suitable end user reachable via any one of interfaces 17. Optionally, other clients 11 may be located at other MGW nodes 25 and/or at other nodes in the network such as at a server node 29, 35, 37, an R-NC node 39, or a BS node 41.

As can be seen in Figure 6, MSB 12 includes a plurality of processors 13 and corresponding clients 11. The DSP host processor bus (DSPH) is used to transfer packets between the shared memory (e.g., SRAM) and the DSPs 13. Another data bus interfaces the FPGA to the shared memory. A board processor interface (BPI) includes the bus from the device board module (DBM) and a general purpose interface. In the MSB 12, the DSPs 13 process packets (e.g., voice streams) upon receiving them. In certain embodiments, only one packet at a time is processed by a DSP. If packets on other channels in the same DSP are received during the period the relevant DSP is occupied, packets are put into queue/buffer. Thus, it is possible to run multiple channels in one DSP and reduce the amount of DSPs on board. Accordingly, DSPs 13 may be shared by this invention as well as other functionalities utilized on MSB 12.

The embodiment of Figs. 5-6 is for purposes of example only and is not intended to be limiting. For example, server 7 may be provided at other nodes of the network as may clients 11.

Once given the above disclosure, many of the feature, modifications, and improvements will become apparent to the skilled artisan. Such other features, modifications, and improvements are therefore considered to be a part of this invention, the scope of which is to be determined by the following claims.

Claims

WHAT IS CLAIMED IS:

1. A system for distributing messages to telephone users, the system

comprising a message announcement server for storing messages and being

characterized by:

a plurality of announcement clients, each of said plurality of

announcement clients being in non-real-time communication with said server; and

wherein each of said clients causes respective messages to be sent to appropriate

telephone end users in approximately real time.

2. The system of claim 1, further characterized in that at least one of said

clients includes a memory of a size less than that required to store a particular message

or message portion therein, and wherein said server transmits said message to said at

least one client in a plurality of separate and distinct message portions at different

times, each of said message portions including a different portion of said message.

3. The system of claim 1, further characterized by a switch and a plurality of

different interfaces (I/F) operatively associated with said switch so that messages are

sent to the end users from clients via the switch and respective ones of the interfaces.

4. The system of claim 1, further characterized in that said server is located

on a first board at a node of the network, and said clients are located on a second board

at said node of the network, wherein said first and second boards are interconnected

with one another via an ATM switch.

5. The system of claim 3, further characterized by at least one switch and at

least one interface (I/F) through which at least one client sends messages to end users,

and wherein said interface (I F) comprises a memory for buffering message streams

received from said client via said switch.

5 6. The system of claim 5, further characterized in that said client includes a

client memory for storing message portions received from said server, and wherein said

client memory is larger than said memory at said interface (I/F).

7. The system of claim 6, further characterized in that message streams are

handled in an asynchronous manner between said server, said client and said I/F, and

LO are handled in a synchronous manner between said I/F and an end user to which

messages are sent.

8. A method of distributing messages to telephone users, the method

comprising a connection handler sending a request to a message announcement server

requesting a message that is to ultimately be sent to an end user, the method being

L5 characterized by:

the server retrieving the message from memory and forwarding the

message to a client in non-real-time (nrt) via at least one switch in a first format;

the client including a memory for receiving the message from the server;

the client changing the message from the first format to a second format

20 and clocking out the message to an interface (I/F) via said switch in the second format.

9. The method of claim 8, further characterized in that said second format

comprises a voice format.

10. The method of claim 9, further characterized in that the first format

comprises one of text, voice, picture, image, and video clip.

5 11. The method of claim 8, further characterized by:

the client clocking out the message to the I/F in an asynchronous manner;

and

the I/F including a synchronizing memory, wherein the I F clocks out the

message to the end user in a synchronous manner.

LO

12. A method of distributing messages to users, the method comprising a

connection handler or message announcement client sending a request to a message

announcement server requesting a message that is to ultimately be sent to an end user,

the method being characterized by:

the server retrieving the message from memory and forwarding the

L5 message to the client in non-real-time via at least one switch; the client including a

memory for receiving the message from the server; and the client clocking out the

message to an interface (I/F) via said switch.

13. The method of claim 12, further characterized in that said client and

server are at first and second respective locations at different nodes of a

20 telecommunications network.

14. The method of claim 12, further characterized in that said client and said

server are at the same node of a telecommunications network, but on different boards at

the node.