MXPA00002320A - Interexchange carrier escape list for local number portability - Google Patents

Abstract

A telecommunications system and method for managing Local Number Portability (LNP) querying for calls routed to Interexchange Carriers by providing a list of carriers in the Service Switching Point (SSP) (local service provider) for whom LNP querying is to be performed by the SSP. For example, calls destined to carriers on the list will be queried by the originating SSP, or other intermediate SSP, and calls destined for carriers not on the list will not be queried by the originating SSP, but instead will be directly routed to the carrier for LNP querying. Advantageously, the local service providers (SSPs) can perform LNP queries for calls destined to certain carriers and charge them for the queries. This will enable small long-distance carriers to provide competitive service in the network by purchasing the LNP querying facility from the SSPs. Furthermore, LNP querying will now be able to be provided for every call routed through an Interexchange Carrier (IXC), regardless of whether the IXC has LNP querying capability.

Description

LOCAL NUMBER PORTABILITY BACKGROUND OF THE PRESENT INVENTION Field of the Invention The present invention relates, in general, to telecommunication systems and to the methods for handling front-end calls, specifically to Service Switching Points (SSP, Service Switching Points) by selectively performing queries from Local Number Portability (LNP, Local Number Portability) for calls routed to Interexchange Carriers (IXC, Carrier between exchanges).

BACKGROUND AND OBJECTS OF THE INVENTION Since the beginning of the telephone in the 1870s, signaling has been an integral part of telephone communications. The first telephone devices depended on the receiving party being close to the receiver at the time of the call. Subsequently, after the formation of the Bell Telephone Company, Watson, Alexander Graham Bell's assistant invented the telephone ring, eliminating the requirement of advance knowledge. By lifting the receiver and allowing the DC current to flow through the telephone and back through the return of the circuit, a spotlight had to be switched on at the operator switch of the exchange to signal to the operator that an attempt was being made to place a call. However, the first signaling methods were somewhat limited because they used the same circuit for voice and signaling. In addition, these were analog and had a limited number of states, or values, that could be represented. At the beginning of 1960, Europe began to digitalize the network, eliminating the signaling of the voice network, and placing the telephone signals in a separate network. With this signaling and voice division, the call set-up and disconnection procedures required with each telephone call were made more quickly, while keeping the separate voice and data circuits for use when a connection was possible, for example, a voice connection is not necessary when the number of the party receiving the call is busy. The Common Channel Signaling (CCS), which uses a digital transmission medium, but places the signaling information in a time slot or channel separate from the voice or data channel with which it is related, is converted into the foundation for current telecommunications. In modern communication networks, signaling constitutes the different control infrastructure that allows providing all other services. It can be defined as the system that allows the control panels to control the stored programs, network databases and other "intelligent" nodes from the network to the central: (a) messages related to the establishment of calls, supervision and disconnection; (b) information necessary for the processing of distributed applications (consultation / response between processes); and (c) network management information. In addition, the Intelligent Network (IN, Intelligent Network) and the new Advanced Intelligent Network (AIN) have made it possible to transfer all types of information through the telephone network without special circuits or long installation cycles. In the IN / AIN, everything is controlled or configured by workstations with user-friendly software. Therefore, representatives of telephone services can create new services and design a service for subscribers from a terminal while talking with the customer. These changes are made immediately and not costly in the switches, rather than by the traditional method: costly changes in programming made by certified technicians. The IN consists of a series of intelligent nodes, each capable of processing at different levels, and each capable of communicating with each other over data links. The necessary fundamental infrastructure is composed of different signaling points, which perform message discrimination (read the address and determine if the message is for that node) and route messages to other signaling points. The three types of basic signaling points are: (1) Service Switching Points (SSP, Service Switching Points); (2) Signal Transfer Points (STP, Signal Transfer Point); and (3) Service Control Point (SCP, Service Control Points), each of which will be described in more detail later. Now with reference to FIGURE 1 of the drawings, the multiple Service Switching Points (SSP, Service Switching Points) 100 service the exchanges in a telephone network 90, a portion of which is shown in FIGURE 1. Across the country, SSP 100 groups are divided into Local Access Transport Areas (LATA, Local Access Transport Areas) 130. Calls placed within a single LATA 130 are handled by carriers of local exchanges (LEC) , for example, GTE, while calls placed between LATA, that is, between separate LATA 130, are handled by Interexchange Carriers (IXC, Inter-Carrier), for example, AT &T, which offers long distance service to customers. within a LATA number. The LEC and the IXC are separate types of SSP 100, which provide local or long distance service respectively to the subscribers. The STP 110 serves as a router or router, and switches the received messages from a particular SSP 100 through the network 90 to its proper destinations (another SSP 100). As is understood in the art, the STP 110 receives messages in the form of packets from the SSP 100. These packets are related to the call connections or queries to the databases. If the packet is a request to connect a call, the message must be sent to a destination end office (another SSP 100), where the call will be terminated. However, if the message is a query to the database looking for additional information, the destination will be a database. The access to the database is provided through the Service Control Point (SCP, Service Control Point) 120, which does not store the information, but acts as an interface for a computer that hosts the requested information. At present, a subscriber in an SSP 100 has the possibility of moving to a different SSP 100 within the same LATA 130 while keeping his public directory number. This is known as local number portability. A key advantage of the portability or ease of transport of the local number is that other subscribers can connect with the transported subscriber without changes in their dialing procedures. If a subscriber has been transported to another SSP 100, the Initial Address Message (IAM) sent by the originating SSP 100 must be modified to take into account the change in the termination SSP, as understood in technique. The Local Number Portability database (L? P, Local Number Portability) is the database that contains Location Routing Numbers (LRN, Location Routing Numbers), which are ten-digit numbers using only to identify the switch that has the number transported. Specifically, the LRN is the number of the receiver switch, which is the switch that has received the number transported from another switch (called the donor switch). This number transported to previously was not served by the receiving switch. Typically, SSP 100 sends an LNP query to SCP 120, which has access to the LNP database to retrieve routing information for a transported subscriber. The response to the query by SCP 120 provides the SSP 100 with the relevant LRN, which is populated (ie, placed) in the Called Party Number (CPN) parameter in the AMI. The Ported Dialed Number (PDN), for example, the actual dialed digits for the subscriber transported from, is placed in the Generic Address Parameter (GAP, Generic Address Parameter) in the IAM. The M bit of the Forward Cali Indicator (FCI, forward call indicator) in the AMI is then updated to indicate that the number has been translated. The M bit of the FCI is used as a failure mechanism to prevent more than one LNP query from being thrown into a call. If the end user has not been a transporter from, the SCP 120 will return the actual dialed number, not the LRN, which will be stored in the CPN parameter. In this case, the GAP is not included in the IAM. It should be noted that the M bit of the FCI is always set to the "Translated Number" after any query of the LNP, however if the end user has been transported from or not. Each subscriber has a Numbering Plan rea (NPA, Numbering Area Area.) With three digits, for example, the area code, and an Office Code associated with it.

(NXX, Office Code) of three digits, for example, the first 3 digits of a seven-digit telephone number.

Each SSP stores within it a list of LNP triggers, which are the NPANXX digit flows associated with the subscribers who have the transport capacity, whether or not any of the subscribers having this NPANXX are actually transported. Each time a call is placed for a subscriber in an SSP different from the calling party's SSP, the originating SSP, which is the SSP responsible for placing the subscriber's call, checks the L? P actuator for the The party receiving the call to determine if a L? P query should be made before routing the call to the switch of the party receiving the call. Each activator of L? P has a condition known as a type of L? P activator criterion associated therewith. The types of trigger criteria of the L? P are indicators stored in the switch by means of commands or other method, which can be set to "consult" or "not consult" depending on the different conditions. Currently, for calls to subscribers having a? PA? XX that is a trigger of the L? P, they are routed to an Interexchange Carrier (IXC, carrier between exchanges), for example, long distance calls, such as dialing 1 more, dialing 10XXX (such as 10288 for AT & T), or dialing 101XXXX, trigger type of the L? P is always set for "query", which instructs the originating SSP to make a query of the L? P to the SCP before routing the call to the IXC, or "no query", which instructs the originating SSP to never perform a LNP query before routing the call to the IXC, regardless of the capability of the IXC to make inquiries about the LNP. Therefore, for conventional systems to be implemented satisfactorily, all carriers (IXC) would need to have the ability to query the LNP to send calls to the transported numbers. Otherwise, calls would be routed to donor switches, which leads to excessive switching and delays. However, with the increase in the number of small-sized competitive access providers (CAPs) entering the market for long-distance carriers, it will not be possible for all small carrier companies to provide the LNP's consultation capacity. Current systems also present a problem in the case where a single switch acts as an extreme office (EO) and an IXC without a call-back loop, which is explained below. Multiple EO / IXC switches have a logical limit between EO services and IXC services. Therefore, when a long-distance call is placed, the EO actually routes the call on the trunk or trunk lines outside the switch back to the IXC on the switch, which allows the EO and IXC to function independently within of the same switch. Thus, for a call to a NPANXX having a trigger type of the LNP trigger "without consultation" associated with it, the EO will route the call to the appropriate IXC, within its switch or to another chosen by the subscriber, for a query of the LNP. However, when there is no logical limit between the EO and the IXC, the internal IXC is used to place a call to a NPANXX having a type of trigger criterion LNP "without consultation" associated with it, the EO / IXC does not perform the LNP query. Instead, the EO / IXC routes the call to the donor switch, thereby incurring costs from the donor switch for an LNP query that the EO / IXC was able to perform. In addition, conventional systems that use LNP queries for routing calls to the IXC do not allow local service providers (SSPs) to have their ability to query the LNP based on a carrier, which is inefficient for the SSP and the IXC. Therefore, it is an object of the invention to provide LNP consultation by the SSP for calls routed to the selective Interexchange Carriers that do not have the ability to query the LNP to avoid routing calls to donor switches. It is further an object of the invention to allow local SSPs to sell their LNP query capability based on the carrier. Still another object of the invention is to allow the EO within the single EO / IXC switch, which does not have the call forward loop capability, to perform an LNP query for the IXC regardless of whether the trigger type of the LNP trigger is established. for "consultation" or "without consultation".

SUMMARY OF THE INVENTION The present invention is directed to telecommunication systems and methods for handling LNP queries for routed calls to carriers (IXC) by providing a list of carriers in the SSP (local service provider) for whom it consults of the LNP must be done by the SSP. For example, calls destined to carriers in the list will be queried by the originating SSP, or other intermediate SSPs where the list is present, and calls destined for carriers that are not on the list will not be consulted by the SSP of origin, but instead will be directly routed to this carrier for the consultation of the LNP. For convenience, local service providers (SSPs) can perform LNP queries primarily for calls destined to certain carriers and charge these carriers for carrier-based queries. This will allow small long distance carriers to offer competitive service in the network by acquiring the ability to consult the LNP from the SSP. In addition, the larger long distance companies may choose to maintain their ability to consult the LNP and not acquire it from the SSP, although there may be cases where the LNP queries are made by the SSPs. Otherwise, large long distance companies may choose to withdraw their capacity to consult the LNP and acquire it from the SSP depending on the specific needs of the company and the cost efficiencies of carrying out the LNP consultations. The innovative systems and methods of the present invention help to avoid routing calls to donor switches, when an IXC is used, allowing SSPs to perform queries of the carrier-based LNP.

BRIEF DESCRIPTION OF THE DRAWINGS The described inventions will be explained with reference to the accompanying drawings, which show important embodiments of the invention and which are incorporated in the specification thereof as reference, wherein: FIGURE 1 is a diagram in blocks that illustrate some of the fundamental components that are used in an Intelligent Network or an Advanced Intelligent Network for signal switching; FIGURE 2 is a flow chart describing a preferred embodiment of the Carrier Identification Code system of the present invention; and FIGURES 3A and 3B are block diagrams demonstrating examples of LNP consultation situations for routed calls to the IXC.

DETAILED DESCRIPTION OF CURRENTLY PREFERRED EXEMPLARY MODALITIES The numerous innovative teachings of the present application will be described with specific reference to the currently preferred exemplary embodiments. However, it should be understood that this class of modalities only offers some examples of the many convenient uses of innovative teaching in the present. In general, the assertions made in the specification of the present application do not necessarily delimit some of the different claimed inventions. In addition, some of the statements may apply to different characteristics of the invention but not to others. Referring now to FIGURE 2 of the drawings, there is shown a preferred embodiment of the PN query system of the present invention for routing calls to the IXC, in which a carrier list, by Carrier Identification Codes (Identification Codes) of Carrier), is defined (step 200) and stored (step 205), for example, as a database in a memory, in the SSPs (local service providers). Once a subscriber places a call (step 210), the originating SSP 100 determines the routing procedure (step 215), for example, by a method known as a B-number analysis, which takes each dialed digit and compares it with a series of translation tables, called plant data, to determine if the call is for your switch or for another switch, within its LATA 130 (intraLATA) or another LATA 130 (between LATA), as is well known in the art. If the call is called interLATA, for example, a long distance call, as determined by the aforementioned B-number analysis method, the originating SSP 100 first compares the NPANXX digit flow marked by the calling party with a list of LNP triggers (step 220), which are NPANXX digit flows having subscribers who can be transported, to determine if the party receiving the call has the transport capacity. If the NPANXX is not an LNP trigger, the originating SSP 100 routes the call to the IXC (step 225) to establish a connection to the terminal SSP 100 (step 250), which is the SSP 100 serving the party. who receives the call. However, if the call is a call between LATA and the NPANXX is an LNP trigger, the originating SSP 100 then checks whether the calling party entered a marked carrier, for example, 10XXX, before the number of the party receiving the call. , or has a pre-subscribed carrier associated therewith (step 230). The Equal Access functionality allows a subscriber to use any IXC for any call, regardless of the pre-subscribed carrier chosen. (If a subscriber chooses an IXC to handle dial 1 plus, the Carrier Identification Code (CIC, Carrier Identification Code), for example, 10XXX, so that the pre-subscribed carrier is stored within the SSP 100 that serves the carrier. this subscriber.) If no carrier is dialed or pre-subscribed, the SSP 100 returns a message to the calling party to choose an IXC to handle the call. Next, the originating SSP 100 verifies the type of trigger criterion LNP (step 235), for example 'consultation' 'without consultation ", for calls destined to the IXC, in addition to other checks, as is well known in the art If the criterion of the LNP trigger is set to" consultation ", the SSP 100 performs the query of the LNP (step 240) before routing the call to the IXC (step 225) However, if the trigger criterion LNP is set to "no query", the originating SSP 100 then compares the Carrier Identification Code (CIC) to the chosen IXC, for example, 10XXX or 101XXXX, with the list of the CICs stored in the SSP 100 (step 245) to determine whether the carrier (IXC) chosen by the calling party instructed to the originating SSP 100 to perform the query of the LNP although the LNP trigger criterion is set to "no query." If the CIC for the chosen carrier is in the list stored in the originating SSP 100, the SSP 100 will perform the LNP query for SCP 120 (step 240). ) before routing the call to the IXC (step 225), however, if the C IC for the chosen carrier is not in the list stored in SSP 100, SSP 100 will not query the LNP, but will route the call to the IXC to perform an LNP query (step 225). The call is then completed (step 250) normally, as is well known in the art. It should be noted that the CIC list stored in the SSP 100 may include the information 10XXX and 101XXXX or, otherwise, may include only the information XXX and XXXX, without the preceding 1 and 0. In the latter case, only the digits after the 1 and 0 associated with each carrier will be compared with the CIC list stored in the SSP 100.

The logical relationship between the SSP and the IXC is further illustrated in FIGURES 3A and 3B. For the case where the trigger criterion LNP is set to "no query", there are two possible solutions, each of which are shown separately in FIGURES 3A and 3B. As shown in FIGURE 3A, the subscriber A 300 that is in a first LATA 315, has placed a call for the subscriber B 350, which has been transported from the switch 2 340 to the switch 3 345 within a second LATA 355 To connect the call, the A 300 subscriber has chosen Interexchange Carrier IXC1 330, as a pre-subscribed carrier or as a marked carrier, which is a Carrier between Centrals without LNP capability. Initially, the originating SSP 310, hereinafter referred to as SW1, must first determine whether the digit flow NPANXX marked by the subscriber A 300 is a trigger L? P. Assuming that the "PA" XX is a trigger L? P, the SW1 310 then determines the carrier identification code (CIC) for the IXC1 330, for example, 10XXX. For the case where the trigger criterion L? P is set to "no query", the SW1 310 then compares the CIC for the 1XC1 330 with a list of the CIC 320 stored in the SW1 310, which are associated with the carriers between exchanges that have paid SW1 310 to perform the L? P query before routing. As can be seen in FIGURE 3A, 10XXX is in the list of CIC 320 stored in SW1 310, and therefore, SW1 310 will query the LNP, through the signaling channels, shown as dotted lines , to SCP 370 via STP 360. Based on the results received from the LNP response, the origin switched SW1 310 then modifies the Initial Address Message (IAM) by placing the Location Routing Number (LRN) , Location Routing Number) for the receiver switch SW3 345 in the Called Party Number parameter and the Ported Dialed Number (PDN, Transported dialed number) for the subscriber B 350 in the Generic Address Parameter (GAP, Generic Address Parameter), as described in the foregoing, and as is well known in the art. SW1 310 also establishes the FCI (bit M) for the "Translated Number", as already described. Then, the SW1 310 routes the AMI in the signaling channels to the IXC1 330 through the STP 360 and occupies a physical channel TI to route the call to the IXC1 330. The IXC1 330 then routes the AMI to the receiver switch SW3 345 by the STP 360 and occupies the physical channel TI to route the call to SW3 345. The SE3 345 then terminates the call on its switch for the subscriber B 350. However, as shown in FIGURE 3B, if the LNP trigger criterion is set in "without consultation" and the CIC associated with IXC2 335, which is capable of LNP, is 10WWW, the origin switch SWl 310 will route the call to the IXC2 335 without consulting the LNP, because the CIC, 10WWW , is not on the 320 list of CICs for whom the query will be performed by SWL 310. In this case, the IXC2 335 will perform the LNP query and modify the original AMI (IAM1) accordingly, as described above. The modified AMI (IAM2) is then sent to the receiver switch SW3 345 by the STP 360, where the call can then be terminated for the subscriber B 350. The list 320 of the Carrier Identification Codes stored in the SSP 310, which are associated with inter-exchange carriers 320 and 335 expecting SSP 310 to perform the LNP queries, together with the types of LNP trigger criteria, for example, "query" or "without consultation", allows the IXC 335 and 330 with LNP capability and without LNP capability, respectively, effectively handle calls transported from, without unduly charging donor switches 340. IXC without query capability of LNP 330 can pay SSP 310 to perform their queries of the LNP and the SSP 310 may charge the IXC 330 for the LNP queries based on the carrier. Therefore, in a preferred embodiment, the LNP trigger type criteria will always be set to "no query" to avoid SSP 310 queries for IXCs that do not have LNP 335 capability. In the aforementioned manner, SSPs 310 will only consult for those IXC 330 that have paid for the service based on the carrier. Furthermore, in the case of an EO / IXC 310/330 switch having a list 320 of the CICs stored inside the switch, which includes the IXC 330 of the switch, the EO / IXC 310/330 is prevented from routing the call to the switch donor 340. For example, if the trigger type of the LNP trigger is set to "no query", the EO 310 will check the CIC 320 list and compare it with the CICs of the IXC 330 used by the calling party. If the IXC 330 used by the subscriber is the IXC 330 within the switch, and the CIC for this IXC 330 is in the list 320, the EO 310 will query the LNP for the call and route it to the appropriate terminal switch 345. As will be recognized by those skilled in the art, the innovative concepts described in the present application can be modified and varied in a wide range of applications. Therefore, the scope of the patented subject should not be limited to any of the specific exemplary teachings described.

Claims (44)

1. A telecommunications system for performing a local number portability query when a call is routed through one of a plurality of carriers between exchanges, the system consists of: a plurality of local service switching points, each of the points of local service switching being connected to at least one of the carriers between exchanges, each of the carriers between exchanges having a carrier identification code associated therewith, a first of the local service switching points having a list of codes stored in it; the comparison means within the first local service switching point for comparing the carrier identification code associated with one of the inter-exchange carriers determined with the code list stored in the first local service switching point, the first point of local service switching by selectively performing the local number portability query for the system when the carrier identification code associated with the particular inter-carrier carrier is in the code list; and the routing means for routing the call through the determined carrier between exchanges to a second local service switching point, the system establishing a call connection between the first and second local service switching points.

The telecommunication system of claim 1, wherein the call has a criterion type associated therewith, the type of criterion being stored at the first local service switching point, the first local service switching point performing the local number portability query when the type of criteria is set to "query".

3. The telecommunications system of claim 2, wherein the type of criterion is associated with local number portability trigger, the trigger of local number portability including a three-digit Numbering Plan Area (Area Numbering Plan) and an Office Code with three digits.

The telecommunications system of claim 3, wherein the local number portability trigger is associated with a plurality of subscribers, each of the subscribers having the transport capability.

5. The telecommunications system of claim 1, wherein the call has a criterion type associated therewith, the first local service switching point performing the local number portability query when the criterion type is set to " without query "and the carrier identification code associated with the inter-exchange carrier determined is in the code list.

The telecommunications system of claim 1, wherein the call has a criterion type associated therewith, the inter-exchange carrier determined by performing the local number portability query when the criterion type is set to "without consultation" and the carrier identification code associated with the particular inter-carrier carrier is not in the code list.

The telecommunications system of claim 1, further comprising a plurality of signaling transfer points, each of the signaling transfer points being in communication with at least one of a plurality of service control points, the first local service switching point by sending the local number portability query to one of the determined service control points through one of the determined signaling transfer points and receiving a response from the determined service control point.

8. The telecommunications system of claim 7, wherein the service control point communicates with a local number portability database to perform local number portability query.

9. The telecommunications system of claim 7, wherein the first local service switching point creates an address message having routing information therein, based on the response, the system using the address message to route the call to the second local service switching point.

The telecommunication system of claim 9, wherein the address message comprises: a Called Party Number parameter, a Generic Address parameter (generic Address parameter), and a Forward Cali M-bit indicator (M-bit forward call indicator).

The telecommunication system of claim 10, wherein the routing information includes a Location Routing Number and a Ported Dialed Number, in the location routing number being located in the number parameter of the party receiving the call, the number dialed, transported being located in the general address parameter, and the forward call indicator of M bits being set to "Translated Number".

The telecommunications system of claim 10, wherein the routing information includes an actual dialed number, the actual dialed number being returned from the determined service control point to the number parameter of the party receiving the call, the M-bit forward call indicator is set to "Translated Number".

The telecommunications system of claim 1, wherein the second local service switching point is a receiver switch.

The telecommunication system of claim 1, wherein the determined inter-core carrier is not capable of performing local number portability query.

The telecommunication system of claim 1, wherein the determined inter-core carrier is capable of performing the local number portability query.

The telecommunication system of claim 1, wherein the first local service switching point is located within a first local access transport area, and the second local service switching point is located within the second local access area. of local access transport.

The telecommunications system of claim 1, wherein the first local service switching point and the determined inter-carrier carrier are located within the same switch.

The telecommunication system of claim 1, wherein the first local service switching point charges the carrier between exchanges determined by performing the local number portability query based on the carrier.

19. The telecommunications system of claim 1, wherein the determined inter-core carrier is a pre-subscribed bearer.

20. The telecommunications system of claim 1, wherein the determined inter-core carrier is a flagged carrier.

21. The telecommunications system of claim 1, wherein the code list consists of a first type of code and a second type of code, the first type of code being "10" followed by a three-digit code, the second type of code "101" followed by a four-digit code.

22. The telecommunications system of claim 1, wherein the code list consists of a first type of code and a second type of code, the first type of code being a three-digit code, the second type of code being a four-digit code.

23. A method for performing a local number portability query when a call is routed through one of a plurality of carriers between exchanges, each of the carriers between exchanges having a carrier identification code associated therewith, the The method comprises the steps of: defining a code list and storing the code list in the first of a plurality of local service switching points, each of the local service switching points being connected to at least one of the carriers between exchanges; comparing the carrier identification code associated with a given one of the., inter-exchange carriers with the code list stored at the first local service switching point; selectively performing the local number portability query by the first local service switching point when the carrier identification code associated with the inter-exchange carrier determined is in the code list; and routing the call through the inter-exchange carrier determined to a second local service switching point.

The method of claim 23, wherein the call has a criterion type associated therewith, the type of criterion being stored at the first local service switching point, and further comprising the steps of: before the step of comparison, perform the local number portability query by means of the first local service switching point when the criterion type is set to "query".

25. The method of claim 24, wherein the criterion type is associated with a local number portability trigger, the local number carrier trigger including a three-digit Numbering Plan area (Area of Numbering Plan) and an Office Code with three digits.

26. The method of claim 25, wherein the trigger of the local number portability is associated with a plurality of subscribers, each of the subscribers having the transport capacity.

27. The method of claim 23, wherein the call has a criterion type associated therewith, the step of performing the local number portability query being performed when the criterion type is established for the "no query" type. and the carrier identification code associated with the inter-exchange carrier determined is in the code list.

The method of claim 23, wherein the call has a criterion type associated therewith, and further comprises the step of: before the routing step, performing the local number portability query by means of the inter-core carrier determined when the type of criterion is set to "without consultation" and the carrier identification code associated with the inter-exchange carrier is not in the code list.

The method of claim 23, wherein the system comprises a plurality of signaling transfer points, each of the signaling transfer points being in communication with at least one of a plurality of service control points, the step of performing being performed by the first local service switching point by sending the local number portability query to one of the service control points determined through one of the given signaling transfer points, and receiving a response from the determined service control point.

30. The method of claim 29, wherein the service control point communicates with a local number portability database to perform the local number portability query.

The method of claim 29, wherein the first local service switching point creates an address message having routing information therein, based on the response, the system using the address message to perform the step of routing 32.

The method of claim 31, wherein the address message comprises: a parameter of the number of the party receiving the call), a generic address parameter, and a (forward-call indicator of M bits.

The method of claim 32, wherein the routing information includes a location routing number and a dialed, transported number, the location routing number being located in the number parameter of the party receiving the call, the number marked, transported being located in the general address parameter, and the M-bit forward call indicator being set to "Translated Number".

34. The method of claim 32, wherein the routing information includes an actual dialed number, the actual dialed number being returned from the determined service control point to the number parameter of the party receiving the call, the dial indicator. the forward call of M bits being set to "translated number".

35. The method of claim 23, wherein the second local service switching point is a receiver switch.

36. The method of claim 23, wherein the determined inter-core carrier has no ability to perform the local number portability query.

37. The method of claim 23, wherein the determined inter-core carrier is capable of performing local number portability query.

38. The method of claim 23, wherein the first local service switching point is located within a first local access transport area, the second local service switching point is located within the second transport area of the local service. local access

39. The method of claim 23, wherein the first local service switching point and the determined inter-core carrier are located within the same switch.

40. The method of claim 23, wherein the first local service switching point charges the inter-exchange carrier determined to perform the local number portability query based on the carrier.

41. The method of claim 23, wherein the determined inter-core carrier is a pre-subscribed bearer.

42. The method of claim 23, wherein the determined inter-core carrier is a flagged carrier.

43. The method of claim 23, wherein the code list consists of a first type of codes and a second type of code, the first type of code being "10" followed by a three-digit code, the second type of code being code being "101" followed by a four-digit code.

44. The method of claim 23, wherein the code list consists of a first type of codes and a second type of codes, the first type of code being a three-digit code, the second type of code being a four-digit code .