GB2385241A

GB2385241A - Use of multiple addresses for receiving messages at a mobile telephone host

Info

Publication number: GB2385241A
Application number: GB0228953A
Authority: GB
Inventors: Jeffrey Wilson
Original assignee: Intellprop Ltd
Current assignee: Intellprop Ltd
Priority date: 2001-12-12
Filing date: 2002-12-11
Publication date: 2003-08-13
Anticipated expiration: 2022-12-11
Also published as: GB0129618D0; GB2385241B; GB0228953D0

Abstract

Identifying messages intended for a host connected to the home network and operable to substitute alternate addresses associated with the mobile host, in order to alleviate message signal congestion in the short message service centre. The message signal, such as an SMS text message signal, includes a destination identifying address such as an MSISDN. In order to alleviate message signal congestion in a network's short message service centre (SMSC) 16, when a determination is made, such as in an SMS Router 30, that the message signal is intended for a host 20 associated with the network, the fixed destination MSISDN is substituted by an MSISDN chosen from a range of possible MSISDNs associated with the same host 20, preferably by rotating through a pre-allocated range sequentially with each succeeding response sent.

Description

TELECOMMUNICATIONS SERVICES APPARATUS This invention relates to a telecommunications services apparatus for use with a mobile telephone system. for processing message signals. The invention also relates to a method of processing message signals.

Many networks support attached devices known as SMS Hosts which can send and receive messages such as SMS (Short Message Service) messages. SMS Hosts are usually third party equipments attached by communication links to the Short Message Service Centres (SMSCs) of a mobile telephone network. The SMS Hosts can receive messages from any mobile phone on any compatible network by means of an MSISDN (Mobile Station ISDN) number. or number range. so that the Host appears to the sending network and any intervening networks to behave as a normal Mobile Station (MS) destination for a Short Message. When the message is received by the mobile telephone network. it is routed to its appropriate Host. rather than to another mobile.

Traffic levels to and from SMS Hosts tend to be peaky in nature. In most cases messages arriving at an SMS host for a particular purpose will all have been sent to the same destination number. This can pose a problem for the operator as a result of the way the GSM system is specified. When a Short Message is sent to Operator A's SMS Host by a mobile subscriber of Operator A. the message first travels to the SMSC of Operator A's network. This SMSC determines the subsequent routing information by querying an HLR in Operator A s network. and then delivers the message to the SMS host. The GSM specification mandates that an SMSC shall not attempt to deliver a second Short Message to the'same number'until the previous message has been acknowledged. For properly implemented SMSCs this typically limits quite severely the throughput of messages to a given destination MSISDN or SMS host.

This leads to three problems. Firstly. if delivery can only be effected at a low rate. the bursty high loading which can result. for example. from a typical voting application can lead to a backlog of messages in Operator A's SMSC. and this backlog can stress the limited resources of the SMSC and may affect other SMS traffic in

Operator A's network. Secondly. the backlog effect can prevent the messages from arriving at the SMS host in a timely fashion. For a voting type event this may unduly limit the number of votes that can be collected. and it is possible that many of the messages still will not have been delivered after the event has finished. Finally. this makes timely interaction with the senders. e. g. for solicitation of a second vote. impossible. and hence reduces possible revenues.

The functionality and operation of Home Location Registers (HLRs) in modem mobile networks is well described by the international standards. Although HLRs may implement proprietary features. the signalling messages which are required to support Short Message reception and transmission are fully defined. Hence also the signalling traffic which results from particular patterns of Short Message traffic is also quantifiable. It is also known that HLR functionality can be divided amongst multiple physical equipments. These equipments are normally geographically diverse and physically similar.

The use of SMS Hosts is also well known. SMS Hosts are usually connected to a mobile network via the Short Message Service Centre (SMSC). using one of a number of standard protocols. Many networks support the reception and transmission of large quantities of Short Messages by attached SMS Hosts.

It is also known that methods exist for accessing these SMS Hosts from other networks. albeit with the throughput restrictions described above. These methods overcome earlier addressing limitations by assigning to the SMS Hosts a range of mobile telephone numbers so that messages can be addressed to them as though they were mobile handsets. This permits access to the SMS Hosts from any compatible mobile network.

Signalling messages can be routed within a network using Signalling Transfer Points (STPs). These have the capabilities to direct messages to preferred or secondary destinations according to an addressing scheme which uses Global Titles.

The MSISDN of the destination mobile telephone or SMS Host has been used as the

Global Title for routing Short Messages. By manipulating the look-up tables within STPs it is possible to control the routing of signalling messages through a network.

STPs can also compensate for non availability of a signalling destination by using secondary or tertiary routing addresses. Global titles can also be assigned to groups of equipments. with STPs used to distribute messages to that title amongst the equipments.

Additional equipments can be placed in a network to intercept certain types of Short Message in order to perform alphanumeric address translation. PCT Patent Application No. PCT/GB02/04853 describes such an arrangement. and the same type of equipment and techniques could be used together with the enhancement described by the present invention to provide the additional benefit of increased SMS throughput.

Messages destined for SMS Hosts in Operator A's network may be sent from other networks. Throughput of messages from other networks to an SMS Host on Operator A's network may be enhanced by a technique disclosed in UK Patent Application No. 0125416.8. This technique may be advantageously utilised in conjunction with the present invention. or either scheme may be utilised separately.

In some cases. an SMS Host attached to Operator A's networks can be responsible for massive levels of SMS traffic and this traffic tends to be peaky in nature. Examples include subscriptions to football results services and televoting resulting from television programmes. It is an aim of at least an embodiment of the invention to remove a major bottleneck in the delivery mechanism at operator A's SMSCs. allowing the low delivery rate of messages from operator A's SMSC to its SMS Hosts to be significantly speeded up.

According to one aspect of the invention there is provided a telecommunications services apparatus for use with a mobile telephone system which has a home network including at least one short message service centre. with at least one host being connected to the home network. the apparatus comprising means for

receiving a message signal which includes a destination identifying address and for determining from the destination identifying address when the message signal is intended for a host connected to the home network. and if so. being operable to substitute for the destination identifying address included in the message signal one of a plurality of destination identifying addresses all of which plurality are associated with the at least one host. such that different message signals to the intended host may be assigned different destination identifying addresses of the plurality thereby alleviating message signal congestion in the short message service centre.

According to another aspect of the invention there is provided a telephone handset for use with a mobile telephone system which has a home network including at least one short message service centre, with at least one host being connected to the home network. the telephone handset comprising means for generating a message signal which includes a destination identifying address and for determining from the destination identifying address when the message signal is intended for a host connected to the home network. and if so. being operable to substitute for the destination identifying address included in the message signal one of a plurality of destination identifying addresses all of which plurality are associated with the at least one host. such that different message signals to the intended host may be assigned different destination identifying addresses of the plurality thereby alleviating message signal congestion in the short message service centre.

According to a further aspect of the invention there is provided a method of processing message signals in a mobile telephone system which has a home network including at least one short message service centre. with at least one host being connected to the home network. the method comprising determining from a destination identifying address included in a message signal whether the message signal is intended for a host connected to the home network. and if so. substituting for the destination identifying address included in the message signal one of a plurality of destination identifying addresses all of which plurality are associated with the at least one host. such that different message signals to the intended host may be assigned

different destination identifying addresses of the plurality thereby alleviating message signal congestion in the short message service centre.

Yet further aspects of the invention provide a computer program for carrying out the above method. and a storage medium on which such computer program is stored.

The invention will now be described by way of example with reference to the accompanying drawings. throughout which like parts are referred to by like references. and in which: Figure 1 is a system block diagram of the original network configuration, with signalling paths showing the manner in which congestion can arise: and Figure 2 is a system block diagram of an embodiment of the invention. showing an improved network with MSISDN substitution.

Referring to Figure 1. there is shown a block diagram of the original network of Operator A including its HLR (home location register) 10. MSC (mobile switching centre) 12. gateway MSC 14. SMSC (short message service centre) 16. and Host interface 18 for communication with one or more SMS Hosts 20. Figure 1 also shows the paths of signalling messages involved in delivering a Short Message from a subscriber of Operator A's network, the subscriber having a mobile station (MS) 22. It does not matter whether the subscriber is currently registered on his home network. or whether he is roaming on a different operator's network (e. g. Operator B's network).

since in both cases the message is first delivered to the Operator A's SMSC 16.

Figure 1 shows the known network configuration. When a Short Message (MOForwardSM) is sent from one of Operator A's subscriber's MS 22 to a Host 20 on Operator A's network. the message first arrives at the SMSC 16 in Operator A's network. This SMSC 16 then queries the HLR 10 in Operator A's network using a

"Send Routing Info for Short Message"signalling message. It receives a"Routing Info for Short Message" response containing both the IMSI (International Mobile Subscriber Identifier) of the destination MSISDN. and the required routing address. After delivering the message (MTForwardSM). a properly implemented SMSC must wait until the delivery has been acknowledged by the SMS Host before sending another to the same SMS Host. This leads to the bottleneck at Operator A's SMSC.

Depending on the implementation of the SMSC. compliance with the limit on deliveries to the "same number" restriction specified in GSM and quoted above may be achieved either by using the destination MSISDN or the destination IMSI. Therefore the bottleneck for a burst of messages to one SMS host will either arise because the MSISDNs are all the same. or because the IMSIs returned in the Routing Info for Short Message"responses are all the same.

Figure 2 shows an embodiment of the invention. constituting an improved network with MSISDN substitution provided by an SMS Router 30. Other parts of the network are similar to that of Figure 1.

The preferred embodiment of the invention uses a Telsis (RTM) SMS Router. manufactured by Telsis Limited. This equipment may be connected to mobile telephone networks using known and standardised signalling protocols including SS7 and TCP/IP. Using well known signalling routing techniques. the mobile network can arrange for SMS messages directed to the network's SMSCs to be routed via the SMS Router. SMS messages may then be forwarded to an SMSC from the SMS Router.

The SMS Routers are said to be in-line with the SMSC's message reception.

The system shown in Figure 2 and the technique described here works by substituting the fixed destination MSISDN number by an MSISDN number chosen from a range of possible MSISDN numbers associated with the same SMS Host. preferably by rotating through a pre-allocated range sequentially with each succeeding response sent. In order to implement this in the home network. it is simply necessary to allocate a range of MSISDN values to each Host. and to arrange for one or more SMS

Routers to implement destination address translation on Short Messages destined for SMS Hosts which have such a pre-allocated number range.

Alternatively the diversification of MSISDN may be achieved in the handset.

This method may advantageously use the capabilities of SIM toolkit. and application infrastructure supported by GSM and the capabilities of modem programmable SIM cards. although other methods are possible. By using SIM toolkit. which can support applications downloaded over the air by the operator, a destination MSISDN entered or selected by the user may be automatically transformed into one of a range of MSISDNs for transmission to the network. and this function may be transparent to the user.

In order to properly implement the message serialisation according to the GSM spec. the SMSC must ensure that no deliveries are currently outstanding to the same Mobile Station (in this case. a Host) before sending another. Whether the SMSC uses the MSISDN or the IMSI to perform this check, use of the present invention allows multiple messages to be'in flight'at the same time. thereby increasing throughput.

A preferred embodiment of the invention works as follows. with reference to Figure 2.

A Short Message is sent by a subscriber using the MS 22. in Operator A's network. This is directed as a"MOForwardSM"Mobile Originated Short Message to the Operator A's SMSC 16. The message travels via the gateway MSC 14 which uses its Signalling Transfer Point (STP) functionality to direct the message first to the SMS Router 30. The SMS Router 30 is programmed to examine the destination MSISDN of all Short Messages. Numbers which correspond to Operator A's SMS Hosts are translated to have a destination address which is taken in a cyclic fashion from a list of numbers associated with that SMS Host. using the SMS Router's own internal look up tables. The key point of the technique is that the destination address may now utilise one of a range of MSISDN values rather than just a single value. By rotating through a range of MSISDN values allocated to this SMS Host. the number of SMS deliveries

which can be'in flight'simultaneously between Operator A's SMSC 16 and Operator A's SMS Host 18 can be significantly increased. thereby reducing or removing the bottleneck at Operator A's SMSC 16.

No changes are required outside Operator A's network. and the same benefit is obtained even when Operator A's subscribers are roaming on another network.

The invention can be implemented as a very low cost solution which can be replicated easily in Operator A's network. Because the MSISDNs of the SMS Hosts do not change continually over time. the implementation of the invention may utilise PROM memory. The addresses of the SMS Hosts which are to be translated by the SMS Router as described may be hard coded into the programming of the machine.

It will therefore be apparent that the above-described technique permits significantly increased throughput of Short Message transmissions from mobile telephone users to SMS Hosts in the home network. This is an important revenuegenerating application for SMS. which is being used increasingly for applications such as voting. advertising and premium services.

Whereas the invention has been described in the context of SMS text messaging systems. it could equally be applied to other messaging systems. for example enhanced messaging services (EMS). multimedia messaging services (MMS) and the like.

In so far as the embodiments of the invention described above may be implemented. at least in part. using software-controlled processing apparatus. it will be appreciated that a computer program providing such software control and a storage medium by which such a computer program is stored are envisaged as aspects of the invention.

GLOSSARY

SMS Short Message Service of the GSM mobile telephone system SMSC Short Message Service Centre PLMN Public Land Mobile Network SMS Host Equipment for sourcing and sinking Short Messages for specific applications SMS Router Equipment which embodies the invention and filters and responds to certain signalling messages.

HLR Home Location Register

Claims

CLAIMS 1. A telecommunications services apparatus for use with a mobile telephone system which has a home network including at least one short message service centre. with at least one host being connected to the home network. the apparatus comprising means for receiving a message signal which includes a destination identifying address and for determining from the destination identifying address when the message signal is intended for a host connected to the home network. and if so. being operable to substitute for the destination identifying address included in the message signal one of a plurality of destination identifying addresses all of which plurality are associated with the at least one host. such that different message signals to the intended host may be assigned different destination identifying addresses of the plurality thereby alleviating message signal congestion in the short message service centre.
2. Apparatus according to claim 1. including a memory storing the plurality of destination identifying addresses associated with the at least one host connected to the home network.
3. Apparatus according to claim 1 or claim 2. wherein the destination identifying addresses are Mobile Station ISDN (MSISDN) numbers associated with the at least one host connected to the home network.
4. Apparatus according to claim 3. wherein the MSISDN numbers of the at least one host are allocated within a defined range.
5. Apparatus according to claim 4. wherein the MSISDN numbers in the defined range are assigned in a cyclic manner to successive message signals for the host or hosts.

<Desc/Clms Page number 11>
6. Apparatus according to any one of the preceding claims. wherein the message signal is a text message signal.
7. A telecommunications services apparatus substantially as hereinbefore described with reference to and as illustrated in Figure 2 of the accompanying drawings.
8. A telephone handset for use with a mobile telephone system which has a home network including at least one short message service centre. with at least one host being connected to the home network. the telephone handset comprising means for generating a message signal which includes a destination identifying address and for determining from the destination identifying address when the message signal is intended for a host connected to the home network. and if so. being operable to substitute for the destination identifying address included in the message signal one of a plurality of destination identifying addresses all of which plurality are associated with the at least one host. such that different message signals to the intended host may be assigned different destination identifying addresses of the plurality thereby alleviating message signal congestion in the short message service centre.
9. A telephone handset according to claim 8. including a programmable SIM card for implementing the address substitution function.
10. A method of processing message signals in a mobile telephone system which has a home network including at least one short message service centre. with at least one host being connected to the home network. the method comprising determining from a destination identifying address included in a message signal whether the message signal is intended for a host connected to the home network. and if so. substituting for the destination identifying address included in the message signal one of a plurality of destination identifying addresses all of which plurality are associated with the at least one host. such that different message signals to the intended host may be assigned different destination

<Desc/Clms Page number 12>

identifying addresses of the plurality thereby alleviating message signal congestion in the short message service centre.
11 A method according to claim 10. wherein the destination identifying addresses are Mobile Station ISDN (MSISDN) numbers associated with the at least one host connected to the home network.
12. A method according to claim 11. wherein the MSISDN numbers of the at least one host are allocated within a defined range.
13. A method according to claim 12. wherein the MSISDN numbers in the defined range are assigned in a cyclic manner to successive message signals for the host or hosts.
14. A method according to any one of claims 10 to 13. wherein the message signal is a text message signal.
15. A method according to any one of claims 10 to 14. when implemented by a telecommunications services apparatus within the mobile telephone system.
16. A method according to claim 15. wherein the telecommunications services apparatus includes a memory storing the plurality of destination identifying addresses associated with the at least one host connected to the home network.
17. A method according to any one of claims 10 to 14. when implemented within a telephone handset for use with the mobile telephone system.
18. A method according to claim 17. wherein the address substitution function is implemented by a programmable SIM card within the handset.

<Desc/Clms Page number 13>
19. A method of processing message signals in a mobile telephone system. the method being substantially as hereinbefore described with reference to and as illustrated in Figure 2 of the accompanying drawings.
20. A computer program for implementing a method according to any one of claims 10 to 19.
21. A storage medium storing a computer program according to claim 20.