DE2003032A1 - Method for searching for free connection paths in a telecommunications network - Google Patents

Description

_ Make: ^ f den '^ Beflin tirid; Wtttökea. '_ ■''■'' Wittäls ^ ächerplatz ·

Method ζχιτπ Search ^ free connection paths in a: -Far-

In the course of establishing connections in a nicntkierartthinefa, A structured communication network is often used: an if e rf ah ie ns, in order to connect to all possible connections s facility one of one one calling. Participant containing switching center to exploit ..

A circuit arrangement is already known in connection with the determination of connection paths between "π"-hen; an exchange containing a calling subscriber and an exchange to be called in a non-hierarchically structured telecommunications network (DBP 1 095 890), with the help of which a connection from the calling subscriber station to the subscriber to be called is set up in that the calling subscriber station emits a signal characteristic of the subscriber part to be called, e.g. the call number of the subscriber station to be called can »Upon delivery of this signal, the switching center containing the calling subscriber station sends out corresponding ·;.) unh commands to all switching centers directly connected to this switching center., The relevant search commands each include the subscriber to be called te he characters risky 'signal. In the switching centers that have now been sown, a check is made as to whether the subscriber parts identified by the search command that has just been recorded are involved in the respective switching center. gepehlosaen int * From these exchanges, if necessary: .. · again corresponding search commands; to the further brokerage associated with the relevant brokerage shares

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.itellen sent out. In these further exchanges the search processes just explained are repeated. During the suohens a free connection path between two to one a multitude of each other through a network of connection paths Connected exchanges are therefore initially from the exchange containing the calling subscriber station from all switching centers that can be reached from this switching center, if necessary via other switching centers of the relevant remote control network. The one from an exchange to the immediately neighboring ones Connection paths running towards switching centers remain the desired ones for the duration of the establishment Connection busy. In the course of the relevant connection establishment measures are still in place to prevent an exchange already activated in the course of a connection is activated again in the course of the same connection. In this way, so-called loops are formed in the Telecommunications network avoided.

A method for searching for free connection paths in an exchange connected to one another by a number of connection paths and each having a plurality of subscriber stations is known (DBP 1 289 884). With this method, information identifying subscriber stations belonging to their respective switching area is stored in the individual exchanges. In a search process, this information is compared with the dialing information identifying a subscriber station to be called produced by a calling subscriber station belonging to the switching area of the respective exchange or from a neighboring exchange. If it does not match the information stored in the respective exchange with regard to all subscriber parts belonging to its exchange area, the Wan! Information is forwarded to the exchanges adjacent to the respective exchange. This forwarding of the information identifying a subscriber to be called takes place together with

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an additional information that enables a connection to be built up from the called: to the calling party, namely via such a forwarding from the relevant switching center to the respective neighboring switching parts only for the duration of the call Connection path, if necessary in an exchange, a match between the dialing information of the called subscriber and one of the designations that can be controlled in the relevant exchange is established the switching center, in whose switching area the called subscriber parts are located, and the switching center, in whose switching area the calling subscriber unit is located, | and further between the called and the calling subscriber parts. In the course of the transmission de r Suchinfo-rmatiön ν ^ n the distribution board containing the calling subscriber to the switching center containing the subscriber station to be called, measures have been taken to initiate the recording and evaluation in the respective switching centers of the switching centers controlled in the course of the transmission of our communication To prevent information that has been received by this switching center in the course of the connection in question. The blocking of the renewed admission or upgrading of the, already in the course of the respective connection building; recorded and evaluated search information erv ^ _N f IGT within a certain Zeitspänne. In this way, the formation of loops in the course of the respective connection setup is also avoided in the known method just considered.

Both in the known circuit arrangement considered at the outset and in the known method considered last, the connection path is finally occupied from the switching center containing the subscriber station to be called to the switching center containing the calling subscriber station Exchange out a pricing of all not in this

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Connection path lying exchanges and the serving exchanges with corresponding other exchanges connecting transmission links. So only for the Time of the final occupancy of the connection routes in question for the respective connection those switching centers or transmission links are released that are not required for this connection. This in turn means that for other currently running searches the available transmission path capacity and / or the number can be reduced at possibly controllable switching centers. In other words, it means that the load of the telecommunications network is relatively high due to the respective searches, despite the respective measures taken took to avoid the loop formation mentioned.

The invention is now based on the object of showing a V / eg how to proceed when searching for free connection paths in a telecommunications network comprising a large number of exchanges connected to one another by a network of connection paths in order to reduce the load on this telecommunications network by the respective "-" search processes to drop as low a value as possible and still take into account all possible connection paths.

The above object is achieved starting from a method of searching free connection paths in a mitei- W Nander by a network of connection paths associated switching centers saved with each designating a plurality of subscriber stations comprehensive telecommunications network, each associated in the individual exchanges to their respective service area subscriber location information which, in a search process with the calling subscriber station belonging to the switching area of the relevant switching center or from a neighboring switching center, identifying a subscriber station to be called

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we ' ¥ ύ'έ tu -.- wäi, p'fiä Bei- Nieh4üi3e ^v re instimjfiüng friii; one of the Ifi de "r ^5. -. je'we'.illge'Ö Vermittiiihgsritellgbeäüglidh. sä-fiitlicher. zu de'r'eri - Verifti fc-tlün'gsbereich.-heard-r'ehdfer iMliaehmer» s- partfi stored-1 nl "dfroatrotten · an · di ^: dgi ^: Wii.tBif & .nuen Veriiiittluiigsstellfe be

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v.iin .welöher-: d (3r · her. geWei-ls ^ benaciibarten? ermiti; l- ■ rteile.-a fine- to-be-called ";Teiinehmersfelle;descriptive"Güehin.f> f5rmatiön ^: her ;, recorded- Worden -ίαϊ-, whereby, on the ufhahme ^ .- e.iner ^ .: VuchinfQ.rmatiön lh: .an switching center - the admission of servant / informat-iDn e'ntsprechelad.er üiichinförmationen in-trains de «construction; The connection in question is prevented and the connection between the switching center containing the subscriber station to be called and the switching center containing the calling subscriber unit is set up via those connection lines via which the S -uch information first in -the -the .. to be called: subscriber station created-. one-r -switching point neighboring switching centers, -. to which the relevant search information is delivered is / this exchange in question as well as the United ~ 'bihduhg, 8ntrfeeke ^ about ^diet: -die.ser Vermittiiingsstelle above-the fed> ^j üohinformation has been, -: and possibly more "with.''This link associated switching centers and . Connection ss trecken.-to ■■ to. the one containing the calling end -'- subscriber station. Switching center and / or until -to -a'r-'ver- 'notiuhgnste-lle are released, - from which the Süchin-Portiation is still too painful. another exchange '■ hih transferred: has been. ■ ^": ■

over and above the well-known BchältUhgsanordhün'g considered obefi ^: this compared to the ' öbkn considered th known method brings ■ the ¹ Br'findUg. The vdr part mi "fc sidii, -that they already during the ^ igie'iitlichen ^ üchvdrgähg ^ s connection sections'}; d,: '' hi availabilty partIeh ttridet connection lines ^ free

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the connection to be established for the actual connection from the respective calling subscriber station to the respective subscriber station to be called are not required. So needs with the arrival of the respective search information in the exchange containing the respective subscriber parts to be called no separate process - no more to trigger for the actual connection of the connecting pieces required or switching centers to be triggered. As a result, the load on the Pernmeldenetzes by viewing processes is reduced to one relatively low value is reduced, without any restriction of the search possibilities associated i: t.

ρ According to an advantageous embodiment of the invention, the Connection from which the subscriber to be called rr; te ι te containing Switching center to the one containing the calling subscriber Exchange through transmission of at least one by the call number of the acknowledgment signal to be called or containing the calling subscriber station to which the calling Participants' parts are sent immediately switched through. This has the advantage of a special :; fast and little effort in individual exchanges connection setup required for the respective connection with himself.

According to a further expedient embodiment of the invention W , the final occupancy of the switching centers designated on the basis of the information stored in the individual switching centers with regard to the search information previously sent out is when an error occurs in the transmission of the acknowledgment signal from the switching center containing the subscriber station to be called to the one containing the calling subscriber station Exchange out repeated at least once. In this way, it is possible in an advantageous manner to prevent any disturbances that may occur during the transmission of the acknowledgment signals

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lead to a falsification of the acknowledgment symbol, switch off if necessary. ^: -, "" ■ '""""■■' ■ · "■■ -

According to a further expedient embodiment of the invention. If an acknowledgment signal evaluated as faulty is received in the switching center containing the calling subscriber station, the connection from the switching center ¹ containing the calling subscriber parts to the switching center containing the subscriber part to be called is re-established with the advantage that, with some degree of probability, the connection is established via a different connection route on which the above-mentioned disturbance of the acknowledgment signal does not occur.

^: ; ■ ■ ■ '■ ^■■::::

According to ⁵ I.Ii yet another expedient embodiment of the invention, in the course of a new search process for free connection paths between the exchange containing the calling subscriber station and the exchange containing the subscriber to be called, the connection is set up to that exchange, from which the Calling subscriber station 'containing switching center which has previously received an acknowledgment character evaluated as faulty, prevented. This measure principally, which is generally applicable in other .also even when search process "or circuit arrangements of the above-considered type, has the advantage that the mit.sich * Wahrscheinlichkelt is relatively high, that in the course of re-ι '-'uchvorgangs another Connection path is selected for the relevant connection than in the course of the first search process.

The invention is explained in more detail below with the aid of a drawing. In the drawing, a Pernmeldenetz is shown schematically, to which twelve exchanges belong, namely the exchanges A "to KL These exchanges A to M are connected to one another in a grid-like manner via connecting links that are connected by lines or radio links can be formed. The transmission of the individual signals and commands between

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the exchanges can take place according to the multiplex principle, namely according to the space division multiplex time division or frequency division multiplex principle. In this context it should also be mentioned that the data to be transmitted between the individual exchanges Information can be pulse amplitude or pulse code modulated.

In the telecommunications network shown schematically in the drawing, it is indicated that at the exchange A and at the exchange M each subscriber station connected int The subscriber station connected to the exchange A. may under the number 567 and the subscriber station connected to exchange E under the number

m can be reached in the telecommunications network. To explain the method according to the invention, it is assumed that a connection is to be established between the two subscriber stations indicated in the drawing. It should be further assumed that the participants parts with the number 5 ^f> '(the calling subscriber station and that the subscriber station is to be called subscriber station with the call number 890 Ent. · Nrechend the above, is from the subscriber station 567 initially Call number 8QO of the subscriber station to be called. This Wan! Information of the subscriber station to be called, which is now used as contact information, is recorded in the exchange A as the exchange containing the calling subscriber station and with the

ψ this exchange compared information stored. This information designates the subscriber stations that can be reached in the exchange area of this exchange A. In the present case, it is determined that a subscriber station under the number 890 is not in the switching area of switching center A. The relevant ouch information (890) is then passed on to the exchanges B and D adjacent to the exchange A, as is indicated in each case by a correspondingly directed arrow next to the connecting links connecting the exchanges to the exchange A. Continue on the relevant arrows

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will be discussed in more detail below. In the exchange A However, it is still saved from where, i.e. from which here Participants this search information has been submitted.

In the switching centers B and D that have now been reached, directional information is first stored with regard to the search information, ie information about the direction from which the relevant search information (890) has been received. In the exchange B, the direction information "1" is stored with regard to the search information (890) and the direction information "1" is also stored in the exchange B. As can be seen, this directional information is the designation that defines the links between these exchanges B and D with the exchange. position A are each assigned. It should be noted that corresponding- | de information can be stored in every exchange that has received search information. This will not be discussed further in the following.

Since, according to the assumption, the desired subscriber station to be called is not located in the switching area of the exchanges B and D - which is determined by comparing the search information with the information stored in these exchanges and the information that can be reached in the switching area of these exchanges - the relevant search information is sent to the forwarded to the exchanges B and D immediately adjacent exchanges. These exchanges are exchanges C, B and Gr. In the exchange E, however, the search information arrives both from the exchange B and from the exchange D. In the present case, it is assumed that the search information from the switching point B arrived at the switching point E before the search information from the switching point

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Recording of the search information in the exchange K from the exchange D is prevented. This is indicated in the drawing by a single X crossing the connection path between exchanges D and E; this means that the link between the switching r parts D and E in the course of searching free connection paths of de. "calling Teilnehmersteiie is 567 released to the party to be called Teiinämerstelle 890 or be freed after-first successful assignment.

In connection with the "" disclosure of the search information from the Switching centers B and D to switching centers C, E and It should also be noted that this prevents the Suoh information is transmitted back to the exchange A again will. It should also be noted that in general in each mediation. ", put measures have been taken to prevent the search information recorded by the respective exchange from being transmitted that connection route is forwarded over which thei-e Search information has just been recorded.

From the switching centers reached in the course of establishing a connection 0, E and G, in each of which it is established that the desired subscriber station to be called in the respective switching area cannot be reached, the search information (890) is passed on to the switching parts P, H and K. While the same processes take place in the exchange K as in the exchanges G and D, the exchanges receive P and H each from two of their neighbors Switching centers are supplied with the search information (890). Corresponding ones are thus played in the exchanges P and H Processes as they have been explained above with regard to the exchange E. In this context it is assumed that 3 in the exchange F the search information (890) first from the exchange E arrives and only then from the exchange C. With regard to exchange H, assume that the search information (89O) is first received from the exchange K arrives at this exchange and only after that

109 841/0647 BATH ORIGINAL

von eier "switching center: C. With regard to switching center H '. iiei assumed that the search information (890) first arrives at this switching center from switching center E and only then from switching center &' .. This has the consequence that "For one 'the' connection ^{path between the switching centers 1} C and P and on the other hand the connection path between the exchanges G and H is released or is generally not used during the relevant connection setup. This ir t, iev.-Eils indicated by the "respective Verbind.ungsstrecke between the respective switching centers cruising X.

"Since it is also determined in the exchanges P, H and K, ie that the desired subscriber station to be called cannot be reached in the respective exchange area, the relevant search information (890) is passed on . The""" mi Switching point K forwards the 3uchinformatiön to the notification parts "L, the switching point H forwards the search information to the switching point L and to the switching point 1, and the switching point P only gives the search information srhli ^ iieh to the switching point 1. In the two exchanges L and 1, the same processes take place as were previously explained in relation to the exchange E, for example. This means that each of these two exchanges L and 1 receives the search information (890) only from one exchange. In this context, it is assumed that the search information (890) J in exchange I comes from the exchange - .. e H be. ' has already arrived, before the relevant search information nViöh 'Daddy of the Vernilttlungssteile P arrives in the exchange I ". Accordingly, the connection path between the two exchanges P and I is released or not occupied at all. In * ents-örechender manner, it is assumed that the Suphlhfnrmation (-89O) is in 'the central office' L first arrived from the switching center K, ^so: that here the encryption 'bihdüngsntrecke -bzw shared between the switching centers and H L. not used at all. Since the desired subscriber to be called is not in the switching area of the

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both mediation:;. '; share L and 1 is reached is passed the 'öurhinformation (8 ^r j °) Aun of those switches, and in both cases ttiungsstelle only to the vermi M. In this case, "ei assumed that the ouehinf ormati one (890) in the Exchange M has already arrived from the exchange 1 when the same search information (890) v> n from the exchange L arrives at the exchange M. Accordingly, the connection link between the two exchanges M and L is released or not occupied, as indicated by a: · X i :: t crossing the relevant connection link. In the exchange M it is determined that the subscriber part to be called is in the communication area of this exchange. If the subscriber station 890 is not involved in any connection, the actual connection can be established between this subscriber station and the calling subscriber station 5 ^ 7 using the information in the exchanges M, I, H, E, B and A with regard to this Connection stored information. As already stated above, direction information relating to the connection in question is stored in the exchanges M, 1, H, E and H. The direction information indicates from which direction the ouchinformation relating to this connection was received in each case. With the aid of an acknowledgment signal which corresponds in a certain way to the book information and which is issued by the exchange M as the target switching section, it is thus possible to use the previously marked or designated connection path from the destination switching section containing the desired subscriber section to be called to the calling subscriber section 567 Outgoing switching parts containing the output switching · ■ parts to be switched through or finally assigned. If the output signal arrives incorrectly in the outgoing switching unit, the sending of this message sign can be repeated by the destination processing unit. Possibly. A new process can also be initiated from the outgoing switching center.

In addition to the mentioned release or non-allocation of the between ein-VIA? / 420/46 ": ^r '-h

1098A1 / 06A7 bad original

individual switching centers existing connection routes in The transmission of search information takes place in accordance with the ! «! Winding now ready for a further release. busy Links and / or 'switching centersν oo is according to the invention immediately after release or non-occupancy the connection path between the exchanges 0 and F in the course of the explained transmission of the search information (890) also the switching center G and also the connection link between the exchanges .. Q and B released. The release of the link between the two Switching centers 0 and B is through this link intersecting letters XX indicated. This is intended to illustrate be that this link as a second ver j link of a link section released * will. The release of this link and the switching center C in the course of the relevant search information transmission is possible, because this switching center C for the actual connection establishment as previously considered has been, does not matter, d. H. not involved in this no will. . ■ - .. ■ ''

In a corresponding manner immediately after release or fiichtbeiegung der connecting link "between the exchanges F and I also frees the connecting link between the exchanges F and E. This is also due to XX indicated that cross this link. Corresponding gj this also applies to all exchanges K and L connecting " Connecting street. This link is also for public inspection their release through letters crossing them XX marked. -

Since the last-mentioned switching center K for the actual connection establishment between the two with one another subscriber parts 567 and 890 to be connected does not matter,

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can now lie difv-e Verrni '. t, .ung.jr. te _L Le with ser Vermi 11 Lung: ;; -, teixe O connecting connection:;: -: tree Ke released, to be. Jier i: t indicated by the crossing letters XXX, appealing ..; now also applies to the connection ;;; -; route between the rental codes G and b and for the connecting pieces between the switches., ..; share J; and A. Accordingly, child marked the;: e verbinjungi-c 'stretch through r.ich je-'vei in crossing letters XXXX or XXXXX.

T:; t the search information (890) in which the desired to be called Participant unit de-axing switch -. Unit arrived, in the present Pali, therefore, in the mediation. '^ te xie M, so .stands for the actual liaison between the to be called Participant parts and the calling participant: ·; teHe only Another connection path is available. All through at least a letter X marked links between, respectively neighboring exchanges are in the course of searching :; free connection routes to the desired subscriber to be called parts containing exchange already released been. This means that the burden on the remote control network is aiso * relatively low due to the search process. At the end of the search process: As can be seen, there is only one connection path marked or provisionally occupied. Then, as already indicated above, the final assignment or connection then takes place this connection paths ?.

Finally, the arrows entered in the drawing next to the connecting links connecting the individual switching parts and the Roman numerals assigned to the arrows should be briefly discussed. The Roman numerals I, II, III, IV and V designate the respective step in the forwarding or transmission of the search information (890), counted from the switching parts A containing the calling subscriber network. The direction of the respective arrow indicates the direction of transmission of the relevant search information. The arrows labeled I ', II ¹ , IIP, IV and V each indicate that a return message is transmitted in the direction indicated by the respective arrow. This fiückmeIdezeichen shows

'' / 420 / 46.0 b _109841/0647 BAD ORfGINAL

ijpr, ieweiügen exchange to, do? · The absorbed by the their respective adjacent Vermittiungsütexle of it just NURP ^ te -find ouchinformation is -worden. So shows z. B. • ieρ l'feiüL V an, since ¹ ? the exchange.:part M has received the search information (890) previously transmitted ^{in the direction lif 1: l'feii.i'V,.} "."

To: Oh, lying down, it should be noted- that? in the individual billing ■ --te.i. len measures cin taken unai prevent "ine as part of a" ouchvorgangs released or not occupied VerbindungSKtrecke not it? This search process is still occupied during the further course. Otherwise could ζ., by transferring the öuchinformation from the Ver I mit t iungsstexie 1- "to the switching center F during the * fifth step V the connection? Route uni further the switching center? be found in the course of the relevant search process, although the mediation.?steile? and just-o aie this exchange ί ^(Λ with the exchanges C -and I joined Verbindungsρtrecken ready have been released i?.) ie f "" medium-occupied links and Vermittiungs-: te ι Ii = P would indeed after . Forwarding of the relevant information are released again; to decrease given additional burden de-- by such movements de.- remote Avoid network but can in each Vermitt ± ungs-: been stored parts by means of which link while fed a Liuchinformation _ "but not included W ith the ^ e. Verbindungr-streeke can then in the course of Yv'eiter- - ~ the relevant üuehinformation of the respective Vermi were ⁴ tlung; .- texie are disregarded 3o eg in Vermii ■ can be trungssteile 1 gesr.eiehert that?.. This exchange has been supplied with search information via the connection link "1" (from the exchange text), which "but has not been recorded." to the exchange3ρ texle P. The same then also applies to the exchanges E, P, H and L.

VT \ ^ / 4-20 / 4 » ^T O b ^ Patent ans test

^'1 § ^{Fi for} BADORIGiNAL

- '"■ ^: " 1 09BA 1/06 47

Claims (1)

Method for opening free connection paths in a rental parts connected to one another by a network of connection paths with a telecommunications network comprising a large number of subscriber numbers in each case, ie: - · .--. En individual rental parts each to their respective Rental: information identifying the area belonging to the subscriber telephony is stored which, in the event of a . ι ο or from a neighboring switching center carried out tr · η, a subscriber station to be called J Ie designating and al :; ijuchj iformation serving "Vahl information are compared welch'- in disagreement with a ^1" in the respective, Vermi ttiungs · Tej he bezfjpiioh pnmtiiolier belonging to broker About calibration ^rl ei] .nei-: mer. "stored information len tei to the of the rental property concerned, all neighboring rental companies 11, lunger; part. ien t ° rr *? iei tet '.vi rd. where in, "each of the · in the course of the -."> u ° henr free connection v / ege controlled entries: 11] .ungr' -: i te iien ^e inf information: ar'Jber is genreichert from softer the i \ .r ieweiJ-: has been men neighboring VeriDittxungr.tei j s single "ine to be called Teilnehmer.-tel Ie significant Ijuchinf ormal i on a.ufgenom-. , where, furthermore, in every exchange.;: -; tene a repeated recording of one and the.-exben ^ uehinformation in the 7th UEP of the ·, lunhenr: free connection paths prevented and the connection rcjtrecice, '; via which the corresponding growth information is currently been transmitted i: -t, is released or not at beiert and wherein ^r di connection between the α ie to call Tei inehmer.steile containing switching center to which the calling Teimehmerstelie containing Vermittiungsnteij.e out over those Vermittlunpr: is set up to share the iber Guchinformation first in the operator containing the subscriber station to be called ung. ^: texie arrived int, characterized in that if the reception of search information is prevented in those switching centers adjacent to an exchange to which the relevant search information has been delivered, this information is y'PA '* / a.kV. / At - * (> V. ί Q q ρ _L - | / Q β i η BATH ORIGINAL The relevant switching center and the connection path via which the search information was previously supplied to this switching center, and, if necessary, further switching centers and connection paths connected to this connection number bif Switching parts are released from which the search information has still been transmitted to at least one further switching center. Method according to Claim 1, characterized in that, upon the transmission of search information from a switching center to a neighboring switching center, an acknowledgment signal is transmitted back from this relevant neighboring switching center to the first-mentioned switching center, on the basis of which the search information can be recorded in the relevant neighboring switching center is shown., Method according to claim 1 or 2, characterized in that the connection from the switching center containing the subscriber station to be called to the switching center containing the calling subscriber station by transmission of an acknowledgment signal containing at least the call number of the subscriber station to be called or the subscriber station calling to the switching center containing the calling subscriber station is switched through immediately. - Procedure according to Claim 3, characterized in that, prior to a final occupancy or through-connection, the; previously sent search information in the individual 'information stored in the switching parts designated switching centers when an error occurs in' the transmission of the acknowledgment signal the transmission of this' ■ sy Acknowledgment signal from which the subscriber station to be called contained. Exchange to which the calling subscriber station VPA 9/420/4630 *> - ■ · '.- ^,. , -1R- included loin switch towards the indr: - · t repeated once '.vird. 5. Verfanren by Anr ^ odor 5 or 4, -iaduroh in - <i> ■. '* ■■ in Recording: 3 incorrect ^ uittungssignaley in the dirrufende Teiinfihmer ~ adjusting containing vermi ttlungs parts * ^r 1', e compound from this exchange ¹ ·: - :. · telie au:, to the connection containing the subscriber parts to be called; sf, part. ie is rebuilt. f>. Method according to claim b, characterized in that in the course of a "renewed search process of the connection establishment to that switching center from which the switching center containing the calling subscriber has received incorrect Ouittungssignai" is prevented. VPA 9/420 / 46-3Ob BATH ORIGINAL 10984 1/0647