MXPA98001677A - Automat addressing technique - Google Patents

Abstract

The present invention relates to the routing of calls from a network (100) to another wall (170) that can be achieved by tracking the call termination history on each group of trunk (1741-1742) connecting the networks. From a knowledge of the call termination history for each route, a termination rate factor (CRF) is calculated which represents the ratio of completed calls to all attempted calls. Then choose the route that has the CRF that represents the highest number of terminations. Typically, the process is dynamic such that if the selected route no longer has the highest number of terminations, then the previously found route that had the highest number of call terminations is chosen. The concept of call termination factor addressing can be extended to multiple carriers to provide a technique for addressing with carrier termination rate characteristics. Addressing can also be completed according to network congestion to advance a flame path

Description

AUTOMATIC ADDRESSING TECHNIQUE Technical Field This invention relates to a technique for directing calls through a telecommunications network. Previous Technique Currently, telecommunications traffic between two endpoints (for example, two individual telephone subscribers) passes over one or more networks. Each network comprises at least one and typically a plurality of trunk groups, each group comprising one or more copper wires, optical fibers or radio channels. The trunk groups run between cubes, each cube comprising at least one telecommunications switch to connect traffic to another cube. Addressing is the process by which each switch chooses an individual trunk group (i.e., a switched pair of conductors or a time slot within a multiple signal or in a fiber or radio sanal). The decision made by each switch to direct calls in a particular group involves a variety of factors. Obviously, trunk operability is crucial to any decision to direct traffic through a particular trunk group. The trunk bandwidth is also important since some kinds of calls require higher bandwidth than others. The trunk length can be important since in general it is convenient to direct calls REF: 25964 on the shortest path. The cost associated with directing a call through a trunk can also be important since the lowest cost path is usually convenient. Switches within an individual telecommunications network may employ one or more well-known addressing techniques to direct calls according to the factors discussed above. Intranet addressing strategies are not necessarily applicable for calls that pass from one network to another. Often, different networks are maintained by different entities. Timely information may not be available outside of a network regarding parameters necessary to direct calls to them. As a result, calls directed to a recipient network may not be completed due to blocking or call congestion, which leads to loss of revenue and customer dissatisfaction. In this way, there is a need for a technique to direct calls between networks that maximize call terminations. Brief Summary of the Invention Briefly, according to a first aspect of the invention, there is provided a method for automatically directing calls between a first network and at least one second network. Initially, calls are routed on the paths that connect the first and second networks. For each path, the history of call terminations in that path is recorded. Subsequently, a call termination factor (CRF = Completion Rate Factor) is established which represents the number of call terminations. In this way, for example if ten calls have been directed on a particular path, and each call has been completed, the CRF for this path is 10/10. If only six of the calls are completed, then the CRF is 6/10. Once a predetermined number of calls has been addressed, the path whose CRF represents the highest number of call terminations is chosen for subsequent addressing. Subsequently, future calls are directed on the selected path. Advantageously, the above-described process of selecting calls is dynamic. In this way, for each call addressed in the selected path, the call termination is monitored. If the selected path no longer represents the highest number of call terminations compared to those previously recorded, then the path that previously had the highest call terminations is now chosen and the call terminations in that call are now tracked trajectory. According to another aspect of the invention, the concept of directing calls based on the highest termination speed can be extended to situations where calls are routed over networks that are maintained by individual carriers. For each carrier, a non-transit speed factor (NTRF) is continuously calculated to track how well the calls are completed to each carrier, without transit through a third country. Directing the calls can then be done based on which carrier has the highest call termination speed without resorting to alternate transit. As with the CRF addressing method discussed above, the NTRF method is dynamic. The NTRF is continuously verified and the carrier selection is based on the most recent NTRF information. Call routing in this manner is referred to as the carrier termination speed characteristic (CCRF = Carrier Completion Rate feature). In accordance with yet another aspect of the invention, a non-terminating condition assorted are trunk blocking is signaled back to a switch that attempts to direct the call on the blocked trunk. Knowing that the call is blocked due to a blocked trunk, the switch then tries to steer on another trunk in order to "advance the route" the call instead of finishing it. BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a block schematic of a telesomunisation network for praising the CRF compression method of the invention.

FIGURE 2 is a flowchart representing the steps associated with the CRF addressing method. FIGURE 3 is a block schematic that shows the symbiosis of the network portion of FIGURE 1 in a foreign network to illustrate the CCRF feedback constraint of the invention. FIGURE 4 is a representation of the flow diagram of the steps associated with the CCRF addressing method of the invention; and FIGURE 5 is a block diagram illustrating the technique of route advancement (RA = Route Advance) of the invention. DETAILED DESCRIPTION FIGURE 1 illustrates a telesomunisation network 100 such as the telesomunisation network that is maintained by AT & T. The network 100 displays a plurality of suota switches (TS's = Toll Switshes), such as TS's 105, 110, 115 and 120. Each TS includes a superswitch model 4ESS previously manufactured by AT &T. The TS's are interspersed by trunk groups (TG's = Trunk Groups) such as TG's 125i-1257. In the illustrated mode, the TG's 125x-1253 asoplan TS 105 are TS 120 while the TG 1254 asopla TS's 105 and 110. TG 1253 asopla TS's 110 and 120, while TG 125e couples the TS 120 with TS 115. The TG 1257 Coupling the TS's 105 and 115.

The TS's 105, 110, 115 and 120 are linked together by a signaling network 130. In the trial, signaling network 130 somersates the SS7 signaling network of AT & T to obtain off-band signaling information at TS The TS's 110, 115 and 120 within the network 100 give service to the sentrals (CO's = Central Offises) for example the CO's 135, 140 and 145. The CO's are of a very strong sonorussus and will not be disproved in detail. For purposes of dissolution, it is sufficient to understand that the CO provides the service (the tone of the marsado) to one or more phone stations (not shown). Each CO directs calls between sentrals that originate from telephone exchanges served by that CO to a corresponding TS. Similarly, the CO directs a call between sentries that receives from its TS address to a terminating telephone station. For this purpose, the CO is blown to a TS by one of TG's 150:, - 1507. In the illustrated modality, TG's ldOi-ldOs assigns CO 135 to TS 110, while TG's 1504-1506 couples CO 140 to TS 120. TG 1507 couples CO 145 to TS 115. To allow direct addressing of calls through the network 100, one of the TS's 105, 110, 115, and 120 is disconnected when a profile of the TG sadastistheses is drawn to that switch. The profile almasenado by sada TG are informacion with respect to the terminations of cersano end and distant (it is desir the ports in the TS's of end sersano and far end where it ends sada trunk), the capacity of the trunk (that is to say its bandwidth ) as well as the trunk type. The profiles of the TGs that coniate TS allow the TS to choose the appropriate trunk group to direct a call using any of several well-known addressing themes. An example of a typical trunk profile is described in U.S. Pat. No. 5,559,877 issued in the name of Gerald R. Ash et al. On September 24, 1996 and assigned to AT & T (incorporated by reference herein). In the illustrated embodiment, the TS 105 represents an internal switching center ISC (International S itshing Center) is a switch that directs calls to a destination foreign network, such as the network 170, through one or more of the foreign networks such The 172x and 1722 networks are used. In this way, the term ISC will be used to refer to TS 105. In order to facilitate dislocation abroad, the ISC links to foreign networks of channel 172 ?. and 1722 through the tronsal 174 groups? and 1742, respectively, while one of the track networks is linked by the trunk groups 175i and 1752 / respec- tively to the foreign network of destination 170. While the profiles of the trunk groups 125x-1257 and 174! -1742 and the twill information of these trunk groups are available in the TS's 105, 110, 115 and 120, the same information of the trunk groups that are spread beyond the foreign track networks 172x and 1722 may not be available to the TS's. In particular, the trunk group profiles may not be available for foreign calls directed to the foreign destination network 170 by the TGs 175J. and 1752. Therefore, dissemination tisnishes that are based on trunk group profiles, may not necessarily be aplimated in dishas sirsunstansias. Referring to FIG. 2, a flowchart representation of the steps of the method of the invention for directing calls under the previously stricken syndromes is illustrated. As it will be expedited from the following dissonance, to sontinuasión this method of diressionamiento will be referred to somo the method of the fastor of velosidad of terminasión (RF) because it takes into account the terminasiones of call. In order to achieve resolution according to the call terminations, a predetermined number of calls are directed to this step 200 (over the groups of foreign trunk bearer trunks such as trunk groups 174a and 1742 of FIGURE 1. Time of each call is recorded together with data as to whether each call was completed (step 205) A failure is marked for the call if a fault signaling message is received from the far end after the call takes an egress trunk (not shown) in a group of trunks If the failure signaling message is not received after the call takes an outbound trunk, then the call will be a success.There is no call termination account for a call that it will not take an egress trunk The ISC (TS 105) maintains a call termination history of success or failure of the last ten (10) calls using a particular route and removes the reg istro oldest and adds the call termination for the most recent call on that route. Based on the number of call endings, a call termination delay is calculated, representing the propulsion of full calls to the total number of calls (step 210). The serge status information of the exit branches, for example, trunk lines 174! and 1742, it is saved by ISC are based on the band of band at rest, reservation of bandwidth and level of plastic. The state of charge of a trunk can be lightly loaded, tightly woven, reserved or osupado. The route that has the highest call termination and the highest-output trunk group (TG) is then chosen as a tray on the sual calls (stage 215). The CRF feedback process is dynamic since the call terminations are followed continuously, as represented by the re-axising of step 205 after step 215. In this way, if TG 174x of Figure 1 has been selessionado, but now suddenly experience a greater number of non-terminations of call, then the calls will be directed on the route that CRF previously calculated, represented the highest number of call terminations. In practice, the call diressionamiento is based on the CRF method previously described, typically employing the following hierarchy as shown in table I. TABLE I STATE OF TERMINATION CONDITION NRFH (no history of recent failure) t "(route) > 300 HC (High Termination) t c (r u t a) < _3 0 0 Cfruta) > HCthrfrtvpe.tc VFN ^ AC (Average Termination) T c (r u t a) < 3 0 0 LCthr (rtype, ts, VFN) < C (path1 <HCthrrrtype.tc. VFNI LC (Low Termination) t c (r u t a) < 3 0 0 Cf path) < LCthr (rtypß rtc. VFN1 Where: rc is the time in seconds since the last recorded call failure for a given route; A route is a path specified by a route type, a destination foreign network (DFN = destination foreign network) or a switch identification, a foreign track network (VFN = Via Foreign Network) or a switching identifi- cation and transport layer (ts); tc identifies the transport capability indicating whether the call is a voice call or a data call where the data rate may for example be 64 kbps, 384 kbps or 1536 kbps; rtype is the type of route, which is one of: first alternate selection, second alternate selection, first overflow selection, and second overflow selection; an alternate route uses a VFN that is the same country as the DFN, while an overflow route uses a third country. C (route) is the termination speed for the route that is the number of complete calls of the last ten (10) registered calls; HCthr (rtype, tc, VFN) and LCthr (rtype, tc, VFN) are the high termination velosity threshold and the terminating speed threshold Ba or respectively for each route type, TC and VFN that are based on Cavg ( rtype, tc, VFN) is indicated in Table II; Cavg (rtype, tc, VFN) is the average number of call terminations (rounded to the most sersano integer) of the last ten (10) calls for all routes with the specified rtype, tc and VFN. This average is calculated for three minutes. Table II lists the thresholds for typical call termination velosity: TABLE II Cavg (rtype, tc, VFN) 0 1 2 3 4 5 6 7 8 9 10 HCthr (rtype, tc, VFN) 5 5 6 6 7 8 8 9 10 10 11 LCthrf rtype. tc. VFN) 3 3 3 3 4 4 4 5 5 5 6 Every three minutes Cavg rtype, tc, VFN) is saved and the thresholds HCthr (rtype, tc, VFN) and LCthr (rtype, tc, VFN) are determined. On a per-call basis, call termination (C (path)) are shaded are the appropriate HCthr (rtype, tc, VFN) and LCthr (rtype, tc, VFN) to selession the route. From the hierarchy indicated in Table I, calls are normally routed on the first route that does not experience a fault or a high termination is a slightly snapped exit trunk group. A route that does not experience failure is defined as follows: Within a pre-determined interval, say 300 seconds, there have been no call failures (as previously defined) in this route. If this route does not exist, then a route that has an average termination speed is a group of slightly sighted departures trunk is chosen, followed by a route that has a low termination velosity are a group of slightly trimmed discharge trunk. If routes are not available, they are a group of slightly outgoing trunk roads, the routes are a group of high-grade departures that are bussan are the order without failure or high termination, average termination and low termination. If there are no available routes, then routes are a group of reserved departures are based on the same order are based on the velosity of call termination. The previously disarrayed terrestrial to direct calls are based on call terminations may be extended to situations where multiple carriers provide connectivity as exemplified in Figure 3 where three separate carriers 170, 1702 and 1703 each serve a destination foreign network (DFN = Destination Foreign Network), in this case DFN 200 such as Tokyo, Japan, of ISC (TS 105). As will be explained below, this type of addressing of the invention will refer to continuation as the digestion of "speed sarasteristisation for carrier termination (CCRF).

In general, the ISC is free to direct intended calls for DFN 200 by any of the carriers 170? 1702 and 1703 (there may be cases where the subscriber calling for solisita a specie of the carriers 170? 1702 and 1703 to transport the In this way, the ISC may not be free to select another carrier In alternate form, the ISC may be under layer to provide a call volume of the calls originating within the network 100 of Figure 1, or that transit through the network 100 to accommodate a specific carrier, thus restricting the capacity to freely designate the first transmission between the carriers). However, if the first-generation carrier fails to direct the call, then the ISC can freely direct the second carrier, they are based on the diressing method, they are a carrier termination velosity feature. Considering that the ISC can freely direct calls between its carriers, 170 ?, 1702, a partisular carrier of agreement is chosen, since the carrier has the highest call termination speed without alternating traffic. Non-alternative transit is defined by the diressionamiento of a call to a foreign carrier that passes directly through that carrier to DFN 200. The fresh air in the call passes through a foreign carrier, let's say the foreign carrier 170? Diffily to DFN 200, it is defined as the non-transit veillessness (NTRF). Alternative transit must be routed through a foreign intermediate route network (VFN) 202 in order to start the VFN 200. This alternate traffic direction is undesirable because the call transport cost is insremented by transport branches. insuridos in directing by VFN 202 to DFN 200.

The routing of calls based on NTRF can be better understood by reference to Figure 4. As illustrated in Figure 4, a pre-determined number of calls are directed by separate carriers 170x, 1702 and 1703 of Figure 3 to collect a call termination history (stage 300). The terminations that are enjoyed by each carrier that do not require alternate transit, are recorded (step 305). In accordance with the call terminations that do not require alternate transit recorded during step 305, a non-transit speedup (NTRF) is scheduled (stage 310). The NTRF is stable from the propulsion of call terminations that do not transit to a third country to total call attempts. The satra carrier NTRF is maintained in the same manner as the terminating veil of the endosorph is kept as shown in Figure 2. The carrier having the highest NRTF is then chosen (step 315). As the CRF dessrito method are respected to Figure 2, the diressionamiento method are sarasteristisas of call termination velosity (CCFR) dessrito are respects to Figure 4 is dynamic, as represented by the flesha that shows the re-axing after from step 305 after step 315. In other words, the NTRF for the selected carrier is qualified as calls are completed by this carrier. In the event that the selected carrier exhibits a fall in call terminations requiring no alternate transit below the one previously sampled for one of the other carriers, then the carrier that previously had the highest NTRF was chosen now. Accordingly, they are still another aspect of the invention. The call sensitivity used by any of the CRF or CCRF theses can be improved by using a sonoside or forward path (RA). Only if they agree is the TASnisa RA, alternate call patterns are chosen to direct if the recipient network has signaled back a songestion of songestion. This can be better understood by referensia to Figure 5. In the past, a directed call from ISC (TS 105) to DFN 200 within country 1 through TG 176 !, but not completed due to songestion, will be withdrawn. These recalled calls result in loss of income and dissatisfaction for the subscript. In accordance with the invention, when a foreign network, such as DFN 200 of Figure 5 serving a country, such as country 1, can not complete a call to DFN 200 as a result of network scanning, then the network signals Foreign companies that are sent back to the ISC by means of a trunk signaling group ((TG) 185, such as a value of partisan sauvage indicating congestion in a signaling release message.) Upon receiving a signal indicating congestion of the trunk serving the DFN 200 , the ISC now chooses a different trunk group, such as TG 1762 and tries to direct the call through a foreign network of way, such as VFN 201. In case the network serving VFN 201 again signals a return When the call is addressed by TG 185, then the ISC will attempt to route the call to a transit country (eg VFN 202) via TG 190. After the call is routed to VFN, an attempt would be made to direct the call. call to DFN 200. In the event that the call still can not be completed, then the call is returned (return maneuver) to the appropriate one of TS's 110, 115 and 120 of Figure 1 that will initially receive the CO call from origin for possible alternative alternating direction by another ISC (not shown). The above describes different aspects of a general technique to direct a call are based on the termination of call. While themes have been devised for aplissations of internal networks, themes are also stackable for nasional network aplissations, metropolitan area network aplimations as well as other network aplissations. It should be understood that the previously disenchanted modalities are merely illustrative of the early stages of invention. Several modifications and sambios can be practiced for those who are skilled in the specialty that will incorporate the principles of the invention and know in their spirit and alsanse.

It is stated that they are relasión to this fesha, the best method sonosido by the solisitante to take to the prástisa the sitada invention, is the one that slaro of the present dessripsión of the invention. Having disassedated the antecedent somo investment, property is claimed as contained in the following:

Claims (15)

1. CLAIMS 1.- Method for directing calls between a first and second networks, characterized by the steps of: (a) directing calls between first and second networks through a plurality of routes, one consisting of at least one group of branches; (b) recording, by a call made through the same route, a history of indiscriminate termination of whether the call will be completed on an exit trunk is a group of exit branches at a far end after a trunk connection; (s) to establish a fastness of terminality (RF) by a sada route are the call termination history; (d) to establish a twilight state for each route, they are based on the link band at rest and reservation and level of traffic on that route; (e) choose between the routes over which future calls may be routed, the route that has a CRF that represents the highest call terminations and the lightest twilight state; and (f) direct future calls on the selesta route.
2. 2.- The method of soundness is the reivindisasión 1, sarasterizado because the termination history is determined are based on itself are received signaling messages of failure from the far end after taking the trunk of egress.
3. 3. The method according to claim 1, characterized in that steps (b), (s), (d), (e) and (f) are carried out repeatedly in succession.
4. 4. - The method of sonification with claim 1, characterized in that the step of choosing a route assumes the stage of choosing the route that has a slightly loaded trunk group of egress.
5. 5. The method according to claim 1, characterized in that the separation stage comprises the step of choosing the route that is without terminating within a pre-determined interval.
6. 6 .- The method of sonification are the claim 3, carasterizado because the pre-determined interval somprende 300 seconds.
7. 7.- The method of soundness is the claim 5, sarasterized because if the route has at least one non-termination within the pre-determined interval, then calls are addressed in the tray that has the highest number of call terminations and disas terminations. call a pre-determined high call termination threshold.
8. 8. The sonification method is claim 7, because if the route has at least one non-termination within the pre-determined interval, and the highest number of call terminations does not exceed the high-call threshold, then the calls are routed in the tray your average number of call terminations exceeds a pre-determined average call termination threshold.
9. 9. - The sonification method is claim 8, which is sarasterized because if the route has at least one non-termination within the pre-determined interval, and the highest number of call terminations does not exceed the pre-determined high call threshold, and the The highest number of call terminations does not exceed the average number of call terminations, so calls are routed in a tray whose call terminations exsend a pre-determined call termination threshold.
10. 10.- The method of soundness is the reivindisasión 5, sarasterizado because the stages are made repeatedly for the routes are groups of departmental branches are heavily serged state.
11. 11.- The sonification method is claim 5, which is sarasterized because the steps are carried out repeatedly for the routes that are reserved trunk groups of egress.
12. 12. A method for directing calls between first and second networks by multiple carriers, each capable of using an overflow path for alternate transit, the method is characterized in that it comprises the steps of: (a) directing calls between first and second networks , by each of the carriers; (b) record by call carrier sada, a history of terminating calls that are transported by the unsuspecting carrier if the call is complete without alternate transit; (s) a non-transit speed factor (NTRF) is established by carrier sada according to the call terminations that do not require alternate transit; (d) choosing the carrier that has an NTRF that represents the highest number of call terminations that do not require alternate transit; and (e) direct future calls on the selesta route.
13. 13.- The method of shielding are the vindication 12, sarasterized because the steps (b) - (e) are repetitively repeated.
14. 14. A method for directing calls between first and second networks through a plurality of trajectories, characterized in that it comprises the steps of: attempting to direct a call through a first path from the first network to a first area within the second net; send from the second network to the first network, a signal if there is congestion that would block the call directed to the first area on the first route and if the songestion exists; and choose when resigning the signal of songestion, a second tray from the first network to the second network to advance in route the call to a second area.
15. 15. The method of compliance with claim 14, characterized in that one of the plurality of routes is chosen in session by receiving a signal of songestion following an attempt to direct a call on the route.