AU2695999A - Method and system for implementing number portability - Google Patents

Description

S F Ref: 461211

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT S S *5

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S

S5

S

S. S

ORIGINAL

Name and Address of Applicant: Amos Aked Swift Pty Ltd Level 3 541 Kent Street Sydney New South Wales 2000

AUSTRALIA

Thomas Amos and Brian Currie 4.

S

Actual Inventor(s): Address for Service: Invention Title: ASSOCIATED PROVISIONAL [31] Application No(s) PP3337 Spruson Ferguson, Patent Attorneys Level 33 St Martins Tower, 31 Market Street Sydney, New South Wales, 2000, Australia Method and System for Implementing Number Portability APPLICATION DETAILS [33] Country

AU

[32] Application Date 5 May 1998 The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5815

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-1- Method and System For Implementing Number Portability The present invention relates to a method and apparatus for implementing number portability across a plurality of telecommunications networks or geographical areas.

The invention has been developed primarily to enable local number portability (LNP) for telephony systems, thereby allowing users to change telecommunications networks or geographical areas without losing an established telephone number.

However, whilst the invention will be described with reference to this particular application, it will be appreciated that the invention is not limited to this field of use.

particular, the invention may be used to enable portability of any number across digital networks, including those of information and premium services.

Background 15 Local number portability has become an important political issue in many "countries. An obvious advantage to telecommunications consumers is the ability to change geographical areas without relinquishing a telephone number with which there may be associated substantial goodwill. However, governmental pressure to increase competition between deliverers of telecommunications services has provided an 20 additional impetus to the implementation of LNP. LNP encourages more effective competition between existing deliverers of telecommunication services because it removes a major impediment to users changing deliverers.

LNP also allows new telecommunications deliverers improved access to the marketplace, since it becomes significantly easier to convince users to change deliverers when the user's telephone number need not change. This is particularly important in countries such as Australia and the UK where telecommunications delivery has historically been dominated by a single company, which was often at least partially controlled by the relevant government. When such telecommunications markets are opened to competition, the original monopolistic organisations are placed in a relatively [R:\LIBE]461211 .doc:mxl strong commercial position, as they initially own 100% of the potential telecommunications customer base. Accordingly, the vast majority of business needed to make a new telecommunications deliverer profitable must be coaxed from the customer base of the original telecommunications deliverer.

Local number portability has been implemented in a small number of countries. One way of providing LNP has been to provide each telecommunications service provider with a database, containing routing details for all customers of all interconnected service providers in the market. By periodically updating their own database, and swapping information with other service providers, each service provider's database remains relatively up to date. However, this arrangement requires o substantial duplication of relatively expensive infrastructure, as well the implementation of protocols for maintaining the completeness and correctness of each database.

Other schemes have used remote call forwarding (RCF) techniques, but this leads to relatively inefficient use of network resources, as well as making multiple 15 number changes and premium digital services access and portability more difficult.

Disclosure of the Invention It is an object of the present invention to provide a method and apparatus for implementing number portability across a plurality of interconnected telecommunications networks, which substantially ameliorates at least some of the disadvantages of the prior art.

Therefore, the invention discloses a method of connecting a first user to a second user which the first user is attempting to call, the first and second users being subscribers of interconnected telecommunications networks, the method including the steps of: providing a centralised database containing network routing information associated with users of the telecommunications networks; obtaining from the database network routing information associated with the second user; and R:\LIBE]46121 .doc:mxl using the routing information to connect the first user with the second user via the interconnected telecommunications networks, wherein the routing information in the database is accessible by a plurality of the telecommunications networks when subscribers thereof attempt to make a call.

The invention further discloses a system for implementing number portability between two or more interconnected telecommunications networks, the system including: a central number routing database including number routing information for users of the telecommunications network; a plurality of interrogation means, at least one of which being associated with each of the telecommunications networks for interrogating the database for number -routing information at the commencement of a call by a first user to a second user of "the telecommunications networks; and connection means for connecting the first user to the second user on the basis of the number routing information supplied by the interrogation means; wherein the central number routing database is accessible by the interrogation means of a plurality of the telecommunications networks.

The invention further discloses a method for facilitating service and physical portability of local service between a plurality of telecommunication carriers, the local service being utilised by users of interconnected telecommunications networks operated by the carriers, said method comprising the steps of: providing a centralised database containing network routing information associated with the users wherein the routing information is accessible by the plurality of networks when users thereof attempt to make a call; obtaining from the database network routing information associated with the users, said routing information being necessary to complete the call; and using the routing information to connect the users via the interconnected telecommunications networks.

IR:\LIBE1461211 .doc:mxl The invention yet further discloses a mediation service that provides telecommunications carriers with an ability to obtain a customised and value added service, said service comprising a system for implementing number portability and an associated method for facilitating service and physical portability of local service between a plurality of telecommunications carriers, the system including: a central number routing database including number routing information for users of the telecommunications network; a plurality of interrogation means, at least one of which being associated with a telecommunications network associated with one of said carriers, said interrogation means for interrogating the database for number routing information at the o commencement of a call by a first user to a second user of the telecommunications networks; and connection means for connecting the first user to the second user on the basis of the number routing information supplied by the interrogation means; S 15 wherein the central number routing database is accessible by the *interrogation means of a plurality of the telecommunications networks; and wherein the associated method including the steps of: providing the centralised number routing database containing network routing information associated with the users wherein the routing information is 20 accessible by the plurality of networks when users thereof attempt to make a call; obtaining from the database network routing information associated with the users said routing information being necessary to complete the call; and using the routing information to connect the users via the interconnected telecommunications networks.

In one embodiment, at least some of the SSPs in the system are located at respective local exchanges associated with the telecommunications networks.

Alternatively, or in addition, at least some of the SSPs are located at respective switches associated with the telecommunications networks.

fR:\LIBE461211 .doc:mxl Brief Description of the Drawings Preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a schematic view of an architecture for implementing number portability between interconnected telecommunications networks according to the invention; Figure 2 is a schematic view of an alternative embodiment of the architecture shown in Figure 1; Figure 3 is a schematic view of another alternative embodiment of the architecture shown in Figure 1; Figure 4 is a schematic view of an "Intelligent Network" (IN) system, for use *with the architectures of Figures 1, 2 and 3; Figure 5 is a schematic view of a first virtually ported user; Figure 6 is a schematic view of a second virtually ported user; S. 15 Figure 7 is a schematic view of a first physically ported user; and Figure 8 is a schematic view of a second physically ported user.

Detailed Description The present invention offers a solution to number portability problems which is particularly pertinent in markets where "Intelligent Network" (IN) capacities of multiple competing carriers are, on the whole, relatively undeveloped, particularly at Local Exchange (LE) level. In many countries, telecommunications and telephony in particular, has been implemented by a monolithic government telecommunications provider. These countries include, for example, Australia and the U.K. As the telecommunications markets in such countries are opened to competition, new telecommunications operators are typically offered at least partial access to the original operator's network, or at least part thereof.

In this scenario, providing each new operator's switches with database facilities to maintain number portability is not feasible on the grounds of cost. This is [R:\LIBE146121 1.doc:mxl -6exacerbated by the need for ongoing information exchange between carriers to ensure that each maintains current number portability details for every subscriber of every network. Furthermore, the cost of implementing the necessary infrastructure disproportionately affects newer, smaller carriers which will usually have significantly less funds available for capital expenditure.

The invention is described with reference to the above scenario, although this is used only as a non-limiting example. In the following text, the original monopoly carrier is referred to a "the main carrier". A first competitor, which is often given governmental assistance, is referred to as "the main competitor", whilst the remaining competitors are simply "other carriers". In the Australian case, for example, the main o. .carrier is Telstra Pty Ltd (formerly Telecom Australia), and the main competitor is Main Competitor Telecommunications Pty Ltd.

In its preferred forms, the present invention is based on IN architecture. Such architecture typically includes four basic components: 15 service switching points (SSP); service control points (SCP); service management systems (SMS); and optionally, intelligent peripherals (IP).

A typical arrangement of these components is shown in Figure 4, although other, more complicated arrangements are also allowable, as will be well known to those skilled in the art.

As seen in Figure 4, an SSP couples to an existing switch or exchange and provides the capability to communicate with the SCP via an STP link. In particular, the SSP is used to switch calls under the control of the SCP. When a first user attempts to call a second user, the SSP sends a request signal to the SCP which in turn replies with routing and other information necessary to complete the call.

The SCP acts as a controlling function for the IN. When the SCP receives the request from the SSP it runs a software application on behalf of the first user. The [R:\LIBE1461211 .doc:mxl -7application uses information sent from the SSP, and from this returns number routing information to the SSP in the form of a set of switching operations.

In order for an intelligent network to function effectively, uniform interfaces are necessary for communication between different components of the IN platform. In a preferred embodiment, communication between the SMS and the SCP is based on the protocol.

In a preferred embodiment of the invention, a Signalling Transfer Point (STP) fits between the SSP and the SCP and is used to route large quantities of transactionoriented SS7 signals between signalling points. The STP effectively provides an SS7 network between the SCP and SSPs.

To perform LNP using an IN the SCP must contain an LNP application which is required to create a LRN. The LRN is an addressing scheme that is used to route ported calls, in which each switch is assigned a unique number that is used to identify it to the network for CAN routing purposes. Other addressing schemes may be used, 15 such as Carrier Portability Code (CPC) and Name and Address. However, LRN is 9. particularly advantageous in that call routing is performed based on the current numbering format.

In an intelligent network, not all of the switches need to have SSP capabilities, and it is possible for non-intelligent switches to relay signalling information to an intelligent switch which will then provide the necessary services. In this scenario, the SSP requires triggering information to be provided by a processing section (not shown), and uses this information when communicating with the SCP. The services available to a user who is connected to a non-intelligent switch are therefore limited by the triggering ability of that particular switch.

Types of Portability There are at least four types of number porting which may be used with the invention: two "virtually ported" types, and two "physically ported" types. These are illustrated in Figures 5 to 8.

[R:\LIBE]46121 1.doc:mxl Virtually Ported The customer is "owned" by a new carrier, but is connected to the Main Carrier's Local Exchange (LE) in the usual way. In effect, the customer has not moved to a new switch, and theoretically, a call could still be delivered to the customer without LNP. The local loop may be unbundled and leased to the new carrier.

The new carrier connects to the Main Carrier's POI (Point of Interconnect), and pays applicable inter-connect fees. Enhanced services are provided either through the local exchange by agreement with the Main Carrier, or through the new carrier's switch if all originating and terminating calls are routed through it.

The inter-connect cost incurred in re-routing the call back over the Main Carrier's local access network after switching the call through the new carrier's switch S• is neutral, since the new carrier will charge the Main Carrier an inter-connect fee for delivering the call, then the new carrier delivers the call to its customer across the Main 15 Carrier network, paying the Main Carrier an equivalent inter-connect fee (less the fee 0 1 for the CAN) if this part is leased by the new carrier. In the case where the Main Carrier acts as an intermediate carrier between two alternative carriers, the recipient carrier would probably pay the Main Carrier an additional trunk switching charge.

The two types of virtual porting are: 1. Inter-connect: New carrier pays inter-connect fees. This arrangement is shown in Figure 5, where the new carrier connects to the POI which in turn connects to the

LE.

2. LE Link: This includes the structure of Figure 5 along with a link to the trunk side of the Local Exchange, as best shown in Figure 6. This link, installed by the new carrier, bypasses the Trunk and Junction inter-connect switching fees, but not the local switching fee (which frequently makes up the bulk of the total fee). The link may be leased, or based on new infrastructure such as optic fiber or microwave networks.

[R:\LIBE1461211 .doc:mxl -9- Physically Ported "Physically ported" implies that all the Main Carrier infrastructure is bypassed.

In this case, the customer is literally connected to a different switch before being ported, thereby requiring "true" LNP. Access to the customer may be provided either by unbundling of the local loop which is leased or bought by the new carrier, or by installation of an alternative Customer Access Network (CAN) such as Hybrid Fibre Cable (HFC) or wireless. A link to the new carrier's switch could be leased, or new infrastructure installed such as fiber or microwave. The two types of physical porting are: 1i. Co-location: The local loop is unbundled and leased to the new carrier. The customer is connected to the new carrier's switch via a concentrator device (eg. an Remote Services Module) RSM)) which is co-located in the Main Carrier's Local Exchange, as shown in Figure 7. The customer's line is patched directly from the 15 Main Distribution Frame (MDF) to the RSM which is linked to the new carrier's switch. Enhanced services are provided through the new carrier's switch.

2. Alternative: The new carrier installs new CAN and junction infrastructure such as HFC or wireless, as shown in Figure 8. Enhanced services are provided through the new carrier's switch.

Referring to the drawings, and Figures 1 to 3 in particular, the invention as presently envisaged includes three preferred embodiments: 1. Local switch intelligence; 2. SSP with Main Carrier IN; 3. SSP with Main Carrier RCF Each embodiment requires that the caller's network make an enquiry of a centralised routing information database, at least when the person being called IR:\LIBE]46121 .doc:mxl subscribes to a different telecommunications network. Such enquiries are referred to as "dips".

In the embodiments described in relation to Figures 1 to 3, the various networks are configured around two major cities, although the actual number of cities (or states, territories, regions etc) is not critical. Also, in these Figures, items designated are Main Carrier infrastructure, whilst items designated are Main Competitor infrastructure.

Local Switch Intelligence The local switch intelligence model (Figure 1) requires an administrator (M) which provides and manages the number portability database facilities, service management system (SMS) and, if necessary, SS7 network (STP) functions. In the local switch intelligence model, carriers with their own local access infrastructure may provide their own SSP-capable switches. Newer, smaller carriers which have yet to 15 implement local access infrastructure may not require SSP-capable switches, as the number portability routing information will be retrieved via the Main Carrier's facilities by the time a call reaches the new carrier's switch.

As shown in Figure 1, this embodiment requires IN capability in the main carrier's local exchanges.

Gap 20 This embodiment provides relatively efficient use of network resources. Since the number portability information is provided at a local exchange level, an efficient route is generated at the earliest possible point in the call.

In this and subsequently described embodiments of the invention, the SMSs of the various carriers are used to ensure the centralised database is kept updated.

A number of scenarios involving calls between various networks will now be described with specific reference to Figure 1.

1. Main Carrier Calling Customer A: A calls F: Main Carrier: A database dip from LE to the Main Carrier's own LNP database (7) determines that F is a Main Carrier customer, and so the call proceeds normally to [R:\LIBE]461211 .doc:mxl -11 customer F via T1 and T2. Alternatively, for Main Carrier callers, the Main Carrier attempts to delivery the call normally and invokes a database dip on the centralised database only if the delivery attempt is not successful.

A calls G.Main Competitor (similarfor H, J, K).

A database dip from LE to the Main Carrier's own LNP database determines that G is not a Main Carrier customer. The enquiry is passed on to the centralised database via the IN, which returns routing information for the call. If G is ported by Inter-connect or LE Link and the destination carrier requires control of the o 10 call, the call is re-directed from to the new carrier's switch (02) via T2. Drop-back may be used by the Main Carrier to release the tromboned lines between T2 and As G is ported by Inter-connect, the call is forwarded from 02 to G via T2 and S• (Alternatively if G was ported by LE Link, the call would have been forwarded from 02 to G via a direct link between 02 and If G is ported by Inter-connect or 15 LE Link and the destination carrier does not require control of the call, there is no redirection and the call is delivered to G as normal.

Alternatively, for Main Carrier callers, the Main Carrier attempts to deliver the call normally and succeeds, since the subscribers are still connected to the Main Carrier switch. This would give the Main Carrier an unfair advantage over other operators, unless it was disallowed.

A calls M.Main Competitor: Since the destination is ported by Co-location or Alternate CAN (eg. the call is forwarded to the carrier for that CAN (ie. transferred from T2 to 02, then delivered to Customer M via 2. Inter-connect Ported Customer D: Carrier B: The calling customer is still physically connected to the Main Carrier local access infrastructure (local loop access and local exchange). The customer is category marked to indicate that the customer belongs to another carrier.

[R:\LIBE1461211 .doc:mxl -12- D calls F:Main Carrier: A centralised database dip from LE determines that F does not appear in the database, since F is a Main Carrier customer. The call is delivered via B2, T2 and D calls G:Main Competitor (similar for H, K): A Centralised database dip from LE returns the routing information, which includes an indication of whether the recipient carrier requires control of call. If the recipient carrier does not require control of the call, it is delivered by the most direct route (B1, B2, T2, Billing information may be transmitted to the recipient 10 carrier through the IN network. On the other hand, if the recipient requires control and G is Inter-connect ported, the call is delivered to G via B1, B2, T2, 02, T2 and If G is LE Link ported, the call is delivered to G via Bl, B2, T2, 02, and via a link between 02 and D calls M:Main Competitor (Physically ported): 15 A centralised database dip from LE returns the routing information for the call to be routed via B B2, T2, 02 and to the ported number destination 3. Physically Ported Customer L:Main Competitor The calling customer is physically connected to the Main Competitor switch either by new local access infrastructure (Alternate CAN), or by the existing CAN connected to the Main Competitor switch (Co-location) L calls F:Main Carrier The Main Competitor database is dipped from 01, returning null. The centralised database is then dipped either from 01 or from returning null (meaning the number is not ported), and so the call is routed to F via the Main Competitor network (02, T2, L calls G:Main Competitor or M:Main Competitor [R:\LIBE]461211.doc:mxl -13- The Main Competitor database is dipped from 01, successfully returning the required routing information to get to G or M, since these are Main Competitor customers. The centralised database is not dipped.

L calls H, J, K.

The Main Competitor database is dipped from 01, returning null. The centralised database is then dipped either from or from returning the required routing information, including whether the call should be routed via the receiving carrier's switch to give it control over the call. If the call is not required to be routed through the recipient carrier's switch, billing information may be transmitted to the recipient carrier through the IN network.

ta For calling customers in a non number portable domain, the call would be treated in the same as manner as under 1. Main Carrier Calling Customer.

S-SSP with Main Carrier IN A second embodiment of the invention is shown in Figure 2. In this embodiment, the required SSPs are provided at switch level only, which results in a reduction in infrastructure at the local exchange level. However, since the call connection routing is already partially established by the time the number routing database is accessed, there is a potential for less than optimum use of network resources. However, in many cases, the potential infrastructure savings will more than offset this disadvantage.

This embodiment requires that any carrier wishing to offer local services to customers have an SSP-capable switch. This avoids the need for implementation of additional trunk and switch infrastructure to allow non-SSP carriers access to the number routing database from local exchanges.

This solution delivers the required portability without high duplication of infrastructure. However, in areas of high local traffic, the interconnect charges levied by the Main Carrier may provide an incentive to other carriers to provide their own partial or full local network infrastructure. For virtually ported services, the local [R:\LIBE1461211 .doc:mxl -14portability function is technically unnecessary if the new carrier's switch needs control over the calls. By contrast, local number portability is an essential facility for physically ported services.

A number of scenarios involving calls between various networks will now be described with specific reference to Figure 2.

1. Main Carrier Customer A.

The Main Carrier dips its own database from T1 to determine whether the called number is a Main Carrier customer. If the called number is a Main Carrier customer, the dip is successful and the call proceeds as normal to customer F via 10 T1 and T2).

If the called number does not appear in the Main Carrier's database the enquiry is passed on to the centralised database via the IN (eg. a call to H:Carrier A or M:Main Competitor). The centralised database returns the appropriate routing information for the call to proceed to its ported destination (eg. customer H or In S 15 the case of customer H (belonging to Carrier the call may or may not be routed via switch A2, depending on whether control over the call is required. If the call is not required to be routed through the recipient carrier's switch, information such as interconnect advice may be transmitted to the recipient carrier through the IN network.

2. Inter-connect Ported Customer D:Carrier B: The calling customer is still physically connected to the Main Carrier local access infrastructure (local loop access and local exchange). The customer is category marked to indicate that this is not a Main Carrier originating customer, but belongs to Carrier B. The called number information is routed to Carrier B's switch and triggers a dip at the centralised database If the called number is not ported, the centralised database returns a null and the call is routed via Carrier B's network to the unported number destination (eg. customer F via B1, B2, T2, If the called number is Inter-connect ported (eg. to G:Main Competitor), the centralised database provides the routing information to route the call via B2, T2, In addition, the call may or may not be routed via the destination carrier's switch [R:\LIBE146121 1.doc:mxl 9 (eg. 02), depending on whether control over the call is required. If the call is not required to be routed through the recipient carrier's switch, inter-connect advice may be transmitted to the recipient carrier through the IN network.

If the called number is Physically ported (eg. to M:Main Competitor), the centralised database provides the routing information to route the call via B2, T2, 02, and 3. Physically Ported Customer LMain Competitor The calling customer is physically connected to the Main Competitor local access infrastructure (eg. cable access), and the trigger for the database dip occurs via 10 the Main Competitor node (01) to the Main Competitor database (Main Competitor SCP) If the called number is a Main Competitor customer the call is routed through the Main Competitor network to the ported number destination (eg. customer G:Main Competitor via 01, 02, T2, ore customer M:Main Competitor via 01, 02, If the called number is not a main Competitor customer, the enquiry is passed on to the centralised database which provides the routing information for the call to be routed via the Main Competitor network to the called destination (eg. customers F, H, J, K via 01, 02, T2, In addition, the call may or may not be routed via the destination carrier's switch, depending on whether control over the call is required.

For calling customers in a non number portable domain the call would be treated in the same manner as Case 1. Main Carrier Calling Customer.

SSP with Main Carrier Call-Forwarding A third embodiment of the invention is shown in Figure 3, in which The Main Carrier utilises existing call-forwarding technology (RCF) to avoid the need for database accesses. Whilst this is a technically inferior solution with respect to network resource utilisation due to the requirements for extra call diversions and some "tromboning" of calls, it is still a feasible way of implementing number portability [R:\LIBE]46121 1.doc:mxl -16between a plurality of carriers. In particular, it may allow relatively robust interim LNP whilst a full in solution is being developed and installed.

This embodiment routes calls in a similar way to that described in relation to Figure 2, except in the case of a Main Carrier customer calling another Main Carrier customer. This is implemented in the following way: 1. Main Carrier Customer A: The Main Carrier attempts to connect the call in the usual way. If the called number is a Main Carrier customer, or is virtually ported to another carrier the call is 10 completed.

RCF -However, if the called number is physically ported to another carrier, RCF is set for the called number on the Terminating Local Exchange, and the call is 00 diverted to the new carrier's switch by forwarding to the new switch identifier, or the S- new physical number.

Summary The present invention provides a novel solution to many of the difficulties associated with number portability. Although the invention has been described with 0 *reference to the portability of local numbers, it also provides the opportunity to make enhanced services both geographically and network portable. This means that information services, mobile telephone services and any other digitally switched service may be made portable with minimal additional infrastructure. This capability can be provided by a number of carriers, working in association with each other in order to provide portability among and between their respective network infrastructures.

Alternatively, or in addition, third party service and infrastructure providers can provide the specialised infrastructure and service capability, making the capability available to telecommunication network providers and/or customers thereof by providing a mediation service capable of supporting customised and value added services. The relatively efficient use of network resources is also an advantage for the [R:\LIBE]461211 .doc:mxl -17future as the amount of data transferred between users increases. Finally, the invention ensures that new arrivals into a market dominated by a relatively small number of telecommunications suppliers are not overly disadvantaged by the need to install large amounts of physical infrastructure at startup. For these reasons, the present invention represents a commercially significant improvement over the prior art.

Although the invention has been described with reference to a number of specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms, without departing from the scope and spirit of the inventive concept.

[R:\LIBE1461211 .doc:mxl

Claims (17)

1. A method of connecting a first user to a second user which the first user is attempting to call, the first and second users being subscribers of interconnected telecommunications networks, the method including the steps of: providing a centralised database containing network routing information associated with users of the telecommunications networks; obtaining from the database network routing information associated with the second user; and 10 using the routing information to connect the first user with the second user via the interconnected telecommunications networks, wherein the routing information in the database is accessible by a plurality of the telecommunications networks when subscribers thereof attempt to make a call. 15

2. A method according to claim 1, wherein step includes the substeps of: causing a service switching point (SSP) associated with the first user to send a routing information request to a service control point (SCP) associated with the centralised database; (ii) upon receipt of the routing information request at the SCP, interrogating the database via a service management system (SMS) associated therewith, thereby to obtain the requested routing information; and (iii) transmitting the routing information to the SSP associated with the first user.

3. A method according to claim 2, wherein the SSP is located at a local exchange (LE) associated with the first user. [R:\LIBE146121 .doc:mxl -19-

4. A method according to claim 2, wherein the SSP is located at a switch associated with the telecommunications network to which the first user subscribers.

A method according to any one of claims 2 to 4, wherein one or more of the telecommunications networks include a local database, the local database containing network routing information associated with users of the one or more telecommunications networks respectively, such that, when the first and second users subscribe to the same network, the SSP associated with the first user need only interrogate the local database for routing information. o

6. A system for implementing number portability between two or more interconnected telecommunications networks, the system including: S°a central number routing database including number routing information for users of the telecommunications network; S: 15 a plurality of interrogation means, at least one of which being associated with each of the telecommunications networks for interrogating the database for number routing information at the commencement of a call by a first user to a second user of the telecommunications networks; and connection means for connecting the first user to the second user on the basis of the number routing information supplied by the interrogation means; wherein the central number routing database is accessible by the interrogation means of a plurality of the telecommunications networks.

7. A system according to claim 6, wherein the central number routing database is associated with a service management system (SMS).

8. A system according to claim 6, wherein the interrogation means take the form of service switching points (SSPs), the SSPs being configured to send a routing information request to a service control point (SCP) associated with the [R:\LIBE]46121 .doc:mxl centralised database, and to receive the routing information obtained as a result of the request.

9. A system according to claim 8, wherein at least some of the SSPs in the system are located at respective local exchanges associated with the telecommunications networks. A system according to claim 8, wherein at least some of the SSPs are located at either or both of respective local exchanges associated with the 6 OV.

10 telecommunications networks, and respective switches associated with the telecommunications networks.

11. A system according to claim 10, wherein one or more of the telecommunications networks includes a local database, the local database containing 15 network routing information associated with users of the one or more telecommunications networks, such that where a first user attempts to call a second user on the same telecommunications network, the interrogation means need only interrogate the local database for routing information.

12. A method for facilitating service and physical portability of local service between a plurality of telecommunication carriers, the local service being utilised by users of interconnected telecommunications networks operated by the carriers, said method comprising the steps of: providing a centralised database containing network routing information associated with the users wherein the routing information is accessible by the plurality of networks when users thereof attempt to make a call; obtaining from the database network routing information associated with the users, said routing information being necessary to complete the call; and [R:\LIBE]46121 .doc:mxl -21 using the routing information to connect the users via the interconnected telecommunications networks.

13. A mediation service that provides telecommunications carriers with an ability to obtain a customised and value added service, said service comprising a system for implementing number portability and an associated method for facilitating service and physical portability of local service between a plurality of telecommunications carriers, the system including: a central number routing database including number routing 055o g 10 information for users of the telecommunications network; a plurality of interrogation means, at least one of which being associated with a telecommunications network associated with one of said carriers, said ,i interrogation means for interrogating the database for number routing information at the S commencement of a call by a first user to a second user of the telecommunications S: 15 networks; and connection means for connecting the first user to the second user on the basis of the number routing information supplied by the interrogation means; wherein the central number routing database is accessible by the interrogation means of a plurality of the telecommunications networks; and wherein the associated method including the steps of: providing the centralised number routing database containing network routing information associated with the users wherein the routing information is accessible by the plurality of networks when users thereof attempt to make a call; obtaining from the database network routing information associated with the users said routing information being necessary to complete the call; and using the routing information to connect the users via the interconnected telecommunications networks. [R:\LIBE1461211 .doc:mxl I 22

14. A method of connecting a first user to a second user substantially as described herein with reference to any one of the embodiments, as that embodiment is shown in the accompanying drawings.

15. A system for implementing number portability substantially as described herein with reference to any one of the embodiments, as that embodiment is shown in the accompanying drawings.

16. A method that facilitates service and physical portability substantially a a 10 as described herein with reference to any one of the embodiments, as that embodiment is shown in the accompanying drawings. o

17. A mediation service substantially as described herein with reference to any one of the embodiments, as that embodiment is shown in the accompanying 2 15 drawings. DATED this Twenty-eighth Day of April, 1999 Amos Aked Swift Pty Ltd a a Patent Attorneys for the Applicant SPRUSON FERGUSON [R:\LIBE461211 .doc:mxl