OA13002A - Telecommunications and telephony network. - Google Patents

Description

013002

The présent invention relates to an integrated télécommunications and telephony network, and in particularto an integrated video telephony, telephony, datatransmission and Internet network, by means ofbidirectional satellite stations/sites.

More specifically, the method for satellite transport of abidirectional type according to the invention uses the IPprotocol and is applicable to two types of networks: 1) "Full-mesh network, by means of which each userterminal can be connected to any other terminal by means ofa single satellite jump (first terminal - satellite -second terminal) and in which the user terminais which areassociated with this "full-mesh network" are grouped into a"Virtual Private Network"; 2) "Star network", which is used to connect user terminais and can be connected to any other terminal bymeans of a double satellite jump (first terminal -satellite - centralised satellite hub - satellite - secondterminal) and in which, in this network configuration also,the user terminais are grouped into a "Virtual PrivateNetwork".

It can thus be seen that it is possible to connect in abidirectional manner user terminais which are located inany part of the world by means of satellite connections,without having to use any longer the land connection knownas the "last mile".

For the purposes of the invention, in the présent description, user terminais complété with a satelliteantenna must also be considered to be ail the embodimentsimplemented on mobile means such as motorised or towedmobile land vehicles, ships and aircreft (in these last twocases use will also be made of automacically aimed antennae 013002 2 which are stabilised on three axes).

Finally, in terms of band, there is a range from 64 Kbit/sto 34 Mbit/s and the services which are supported canconsist of various major applications, such as videoconférences, video telephony, compressed-mode telephony,data transmission and accessibility to the Internetnetwork.

The normal télécommunications Systems which are currentlyoperative for fixed telephony briefly include thefollowing: a physical System for collection from the clientto the first switching exchange, a sériés of Systems fordistribution of the physical connections between the clientand the exchange, such as, for example, to assure promptdétermination of faulty cables, and interchangeability ofthe utterances of the client in relation to the exchange, asériés of switching Systems, and the transport Systems.

However, the traffic is always collected by means ofphysical connections, which usually include copper carriercables leading from the location of the client to the firstswitching location (exchange).

Similarly, the transport Systems also use carriers whichare made of copper, or use radio bridges with a carrierfrequency, or with optical fibres.

Thus, in the conventional télécommunications Systems forpublic use, in order to allow broad-band services to reachthe location of the client, it is necessary to use opticalfibres or physical cables of a balanced or coaxial type;furthermore, the transport by radio is always carried outwith fixed-carrier Consolidated technologies.

In addition, as far as GSM telephony Systems in particularare concerned, in relation to so-called international 013002 3 roaming, the présent situation is particularly critical,especially from the point of view of the operators, since,firstly, no operator can hâve direct control over costsincurred by the client during roaming conversations; thislimits considerably the inputs of any téléphoné operator.

In addition, it is not possible for the operators themselves to offer pre-paid cards to clients who makeroaming téléphoné calls.

Finally, the téléphoné costs of these conversations arealways too expensive for the clients, and it is alsoextremely difficult to access the various voice-mailfacilities activated by the users.

Within the context of the requirements previously described, the object of the présent invention is toeliminate the aforementioned disadvantages, by providing atélécommunications and telephony network which guaranteesgeographical connection, bidirectional satellite loop, orconnection of the "last mile", points of access fordedicated mobile devices, global connectivity between theusers of the same network, as well as with users ofnetworks which belong to other mobile or fixed telephonyservice companies, and integrated connectivity withconnections of a satellite type.

The technological innovation of the présent invention incomparison with the existing Systems which use satelliterouters is to permit transparent transport of data flows(for example of type El at 2 Mbit/s with a G.703/G.704interface) which are not oriented to the connection bymeans of satellite routers, which are necessarily orientedto the connection.

This makes it possible to transport transparently the so-called junction connections, comprising in the data flow 013002 4 both the signais between the network nodes and the voiceframes between the public téléphoné switching exchanges atany hierarchical network level, base radio stations andcorresponding control stations for mobile telephony Systemsand private (PBX) and public switching exchanges.

Thus, owing to the numerable El interfaces présent on thesatellite router, the connection can be of the point-to-point type rather than of the point-to-multi-point type,with considérable advantages in terms of economy. of scale.

Spécifie applications of this technological innovation withsatellite connectivity are associated both with use forTETRA Base Stations (TBS), with the Digital ExchangeSystems (DXT) of the TETRA network, and with the networks(GSM) between the Radio Base Station (RBS) and thecorresponding Base Station Control (BSC); furtherapplications include data transport on standard UMTS andMMS networks.

In these applications the flows at 2 Mbit/s of the El typewith a structured G.703/G.704 interface are transported inbidirectional mode.

In practice the technological innovation is based on asatellite router of which both the software and hardwarehâve been modified correspondingly, whiçh permitstransparent transport of the data flows to be joined to therouter itself in transmission and in réception; the idea isto provide by means of bidirectional satellite connectionthe possibility of transporting the data flows with speedsof between 2 Mbit/s and 34 Mbit/s for the interconnectionof public and private switching Systems.

Another object of the présent invention is to provide anintegrated télécommunications and telephony network whichguarantees complété vocal, data, fax and video 013002 5 connectivity, and points of access for mobile telephony andInternet access.

Another object of the présent invention is to provide atélécommunications and telephony network which enables thetéléphoné operator to hâve complété control over the costsof the calls and over the téléphoné traffic generated bythe users in international roaming, also guaranteeing thepossibility of offering pre-paid téléphoné traffic andprices which are lower than those applicable hitherto. A further object of the présent invention is to provide atélécommunications and telephony network which makes itpossible to obtain new financial inputs, both for thetéléphoné operators and for the companies which arepartners of the roaming operators.

Another object of the invention consists of providing atélécommunications and telephony network which usestechniques and components which are normally used in theconventional Systems for transport of signais, and whichhas a substantially simple design and is economical toimplement as an investment, owing to the advantagesobtained.

These and other advantages according to the présentinvention are achieved by providing a télécommunicationsand telephony network, as described in claim 1, to whichreference is made for the sake of brevity.

Other characteristics of the présent invention are alsodefined in the successive daims. Advantageously, thenetwork according to the invention is designed for usewithin the context of fixed telephony and/or videotelephony, however without excluding mobile/fixedintégration. 013002 6

In particular, for the connection of the "last mile", ituses a bidirectional satellite radio bridge and abidirectional satellite station/site which is connected bymeans of the wiring of the building vertically to an IPvideo téléphoné.

Unlike the conventional Systems which are opérâtive atprésent, the télécommunications and telephony Systemaccording to the invention collects the traffic byproviding, depending on the cases and also in the spécifiecase of fixed telephony, only small lengths of copper cablefrom the client base to the roof itself of the client base,where there is présent a first network device withcollection functions; the client base can therefore bereached directly by radio by means of devices whichcommunicate between the client base and the roof of thebase, as in the case of mobile or cordless téléphonédevices,· the transport is carried out by bidirectionalsatellite radio bridges.

The network according to the invention also transportsbroad-band integrated services digitally via satellite,directly to the client base, as well as the normal fixedtelephony services.

Use is also made of low émission power levels (normallylower than 20 W for each individual device); which however,owing to the orientation of the antenna, which is disposedat an élévation of 30-40°, create very low levels ofelectro-magnetic field on the horizontal plane.

This involves use of a considérable number of stations,which however can be self-supplied, by means of theinstallation of small solar panels (owing to the low powerlevels used). 013002 7

The fact of using low power levels has another clear advantage, consisting of the very low level of electromagnetic pollution.

The system also guarantees vocal, data, fax and videoconnectivity, and points of access for mobile telephony,Internet access and video telephony.

The central core of the network, which guarantees connectivity between the various local exchanges and localresidents' exchanges, is based on an IP (Internet Protocol)network structure, whereas at local level, the user hasstandard téléphoné numération available in order to accessthe service.

At the level of the local exchange, there is transformation, which is transparent to the user, ofrouting based on standard téléphoné numération, intorouting based on the IP protocol, and similarlytransformation of the digital or analogue signal (whichcontains the vocal, fax, data etc information), into datapackages which are based on the IP protocol; in addition,in order to guarantee greater connectivity between thevarious resources, at a lower cost than in the knownsolutions, algorithms for compression of the informationare applied.

As previously stated, the local user accesses the localtéléphoné exchanges by means of bidirectional satelliteradio bridges or stations/site; at the level of the localexchange, the téléphonie flows obtained from various localradio bridges are incorporated, compressed and digitised,such that they can be transmitted on a network which isbased on IP protocol, produced by means of connection onbidirectional satellite radio bridges, for connection atthe level of local residents (between district exchanges),and with a satellite radio carrier, or using other 013002 8 technologies, for connection between different towns.

Finally, the System according to the invention provides afixed telephony network, comprising various contents withadded value, which is completely independent from theconventional service companies, and from the physicalcarriers which are used as standard by the latter for thecréation of a complété telephony network.

Connectivity is guaranteed completely between users of thesame network in a local, local résident, régional, nationaland supranational environment, as well as between users ofnetworks of other service companies.

The System according to the invention can also control ailthe flows of information and data which are currentlyavailable on conventional telephony networks (local calls,fax, data and video transmission, video telephony and videoconférences, Internet access, points of access for mobiletelephony).

In particular, the video telephony Systems are supported byappropriate devices which use the IP protocol at connectionlevel, such that the video telephony itself can occupy aband of between 128 Kbit/s and 384 Kbit/s.

The System in question also transports a plurality ofservices in a single duct, thus enabling the controloperator to avoid having to use a plurality of physicalmeans in order to offer different services.

Finally, the System can be installed quickly and easily,since it does not require excavation work, with ail theconséquent potential problems (permits, passage throughhistorié town centres, any damage, etc), it is moreeconomical than the conventional Systems, owing to thelimited power levels of the devices and the relative 01300 2 9 simplicity of the network architecture, and has considérable flexibility and simplicity of use for thenetwork operator, which can also control and manage theentire System from several points, or from a singlenational node.

Further characteristics and advantages of a télécommunications and telephony network according to theprésent invention will become more apparent from thefollowing description, provided by way of non-limitingexample with reference to the attached drawings, in which:-figure 1 illustrâtes schematically a method according tothe présent invention, for connection of local accesses offixed téléphoné devices, to a télécommunications andtelephony network; -figure 2 represents schematically a method according tothe présent invention, for connection of local accesses ofcellular téléphoné devices to a télécommunications andtelephony network; -figure 3 represents a block diagram of a télécommunications and telephony network according to theinvention, connected to téléphoné networks for localrésidents; and -figure 4 illustrâtes schematically an example of globalconnection to the various local accesses of atélécommunications and telephony network for localresidents, according to the présent invention.

With particular reference to figure 1, it can be seen thatthe architecture of the network according to the inventionis based on different levels, subdivided hierarchically,wherein the lowest levels comprise a first sériés ofconnections, indicated as CO, Cl, of the local users UL ofa local access AL to local centralising devices MD, and ofthe said local centralising devices MD to the localexchange GV: these connections are formed mainly by meansof data flows of the type El, at 2 Mbit at least. 10 013002

The highest levels, relative to the connections C2 betweenthe local exchanges GV, the local residents' exchanges,régional and national exchanges, and the nodes for accessto the networks of other service companies AG, areconnected by means of data flows which are organisedaccording to the protocol TCP/IP.

At the highest levels, the fixed telephony network ATaccording to the invention is based on a conventional IP(Internet Protocol) structure, on which the standardtelephony is transformed into telephony of the "Over IP"type.

One of the main innovative aspects of the network which isthe subject of the présent invention is the use, in most orail of the connections, of connections Cl, C2 of thebidirectional satellite type, which are diversifiedaccording to the level of the network through which thesignal is passing.

The only portion of connection based on physical carrierswhich are not of the radio type, is the connection,indicated as CO, between the final user UL (téléphoné oranalogue modem) and the local centralising device MD, whichconsists of a multiplexer/demultiplexer, which generates aflow El with 2 Mbits, standard G.703/HDB3; in fact, thisconnection is normally formed with cabling by means of atéléphoné pair or optical fibres.

The local centralising device MD is normally always présentin the same stable unit as the final user, and canincorporate up to a minimum of 30 téléphoné callssimultaneously.

If required, the final user can be connected to themultiplexer by means of one or a plurality of lines, or can 013002 11 activate a connection of the ISDN type, with a minimum of64 Kb, or a variable or fixed band data connection,according to the capacity required at that moment fortransport of the video, audio or data flow.

As an alternative to the conventional fixed telephonyconnection, it is possible in addition to create a sériésof points of input (local accesses indicated by ALI) to thetelephony network AT, according to the invention, fortéléphoné devices of the cellular or cordless type TC.

Usually, the cover for cordless or mobile téléphoné devicesTC guarantees an environment which is restricted to thebuilding or to the area adjacent to the building itself,although greater cover is not excluded if the area of thefinal user is well covered by radio cells CR.

The signais C4 received by the radio cells CR are indigital format, and are obtained from the mobile téléphonédevices TC; in this respect, see also the diagram infigure 2.

At the output of the cells CR, there is présent a digitalflow, indicated as C41, of standard type G.703/HDB3, with2 Mbits.

One or a plurality of flows with 2 Mbits, of the typeindicated as C41 and obtained from the cells CR, are sentto a compression and conversion device GV (gateway), whichcompresses and converts signais C41 into IP protocol.

At the output of the device GV, the 2 Mbit signal in IP,which is indicated as C5 in figure 2, is sent to a routerR; the router R addresses the various signal packages inthe required directions, in accordance with a configurationwhich is decided by the network service company. 013002 12

Thus, downstream from the device R, the signal C6 can, forexample, equally well be conveyed to a bidirectionalsatellite connection ST, or it can be transmitted toanother point on the telephony network AT.

The connection between the different points of the networkAT can take place on a single-hop basis (direct connectionbetween the local centralising device MD and the localexchange) or on a multi-hop basis (connection carried outby means of intermediate repeaters between the localcentralising device MD and the local exchange).

Leading to the local exchange CL there are one or aplurality of data flows El, with 2 Mbit of standard G.703,indicated as C7 in figure 2, which are obtained from one ora plurality of local centralising devices MD, or fromaccesses to the networks of other service companies AG,based on data flows of standard SS7 (indicated as C8 infigure 2), single connections with local users, by means ofpairs or optical fibres, and points of access for mobiletelephony.

At the level of the local exchange CL, the standardtéléphoné flow is converted into a flow according to the IPprotocol, and the highest levels of the network AT, whichguarantee the connection between the local exchanges CL,the exchanges for local résidents, régional and nationalexchanges, and the nodes C2 for access to the networks ofother service companies, are organised as a standardnetwork of the type with IP protocol.

In order to implement this type of telephony, it is thusnecessary to transform the information, whether it is inthe form of voice, fax, video or data, in whatever formatit reaches the local exchange CL (flow El with 2Mbits,standard G.703, single digital or analogue signal, SS7 dataflow) into a flow of homogeneous data, such as to be 013002 13 transportée! on a network with a package based on thestandard protocol TCP/IP (Internet standard protocol); inaddition, it is necessary to transform the process ofrouting téléphoné calls based on téléphoné numérationspécifie to the téléphoné networks, by replacing thestandard téléphoné numération, at network level, byaddresses according to the IP protocol.

This process is altogether transparent at levels of localuse, and is implemented by means of an applicativeprogramme for control of the network.

The device which Controls the conversion is the conversionand compression device GV, which in practice consists of amulti-protocol gateway device.

Each local exchange CL is equipped with at least one devicefor conversion and compression GV, which thus processesdifferent types of inputs (for example one or a pluralityof flows El G.703, one or a plurality of single digital oranalogue signais in multi-protocol, whilst distinguishingone from another, or one or a plurality of data flows SS7),and transforms them into data packages based on thestandard protocol TCP/IP.

At the same time, it converts the standard numération intoaddressing of the IP type, and Controls the transmission ofcorrectly addressed packages on the high hierarchicallevels of the AT network, in IP protocol.

The conversion device GV also permits the opposite passage,and thus conversion of the data flows in IP standard (highhierarchical levels of the AT network) into the data flowssent to the local user, or to users of networks of otherservice companies (transformation into flow El, standardG.703, into a single digital or analogue signal, into SS7data flows, etc). 013002 14

In addition, since it can obtain digital data, byimplementing algorithms for compression both of the vocalinformation and of the addressing in the IP protocol, thedevice GV makes it possible to obtain a réduction of theprogrammable and variable data flows which is up to 10times the nominal level (compression ratio of 10:1). Thisinvolves a further saving in infrastructures, leading totéléphoné charges which are far more advantageous for theuser.

At the level of the local exchange CL, the local residents'exchange and the régional exchange, control of téléphonécharges is also provided, in the sense that each exchangeis autonomous in calculating the charges to the users whichare directly connectedto it; the bill may or may not thenbe sent to one or a plurality of accounting collectioncentres, which subsequently control and collect thepayments.

To summarise, the device GV permits transformation of thestandard téléphoné flow which enters a data flow incompressed IP protocol, permits transformation of theprocess of standard téléphoné routing into IP protocolrouting, and guarantees control of the téléphoné charges,and transformation of the flow of data in compressed IPprotocol into a standard téléphoné flow output.

The data flows in IP protocol which are output from theconversion devices GV must be routed on a network which isbased on IP protocol, and thus, each device GV is connecteddirectly to a local routing device R in IP protocol, bymeans of a 10/100 data flow BaseT.

In the network topology in IP protocol, the device GVrepresents a gateway device for local access or accessoutside the network AT. 013002 15

The télécommunications and telephony network AT accordingto the invention, at IP protocol level, consists of varioushierarchical levels, which are subdivided into a localnetwork (district), local residents' network, régionalnetwork, national network, and supranational network.

Routing within the network AT is controlled directly bythe dedicated devices, indicated as R, in IP protocol,which are connected to the local compression devices GV, orto satellite routing devices RS, or to radio bridges PR,which permit interconnection between networks RLC at thelevel of local residents (in this respect see the diagram.in figure 3); in particular, at the level of localresidents, the data flow output from the routing device Ris sent to the other routing devices R, mainly via aconnection, indicated as RLD, with bidirectional satelliteradio bridge technology, in frequency bands which aredépendent on the country in which the network AT isoperating (in this case also, the connection can take placedirectly or by means of intermediate repeaters).

At the level beyond that of local residents (connectionsbetween different towns or régional locations), theconnection can also take place with conventional Systems,such as optical fibres, coaxial cables, radio bridges orthe like, but it takes place mainly by means of a satelliteconnection node ST (geostationary satellite), wherein therouting device R is connected to the satellite transmissiondevice with a data flow of 10/100 BaseT.

The satellite connection ST has a capacity which isvariable according to the traffic required by the networkAT that moment, starting from a minimum of 64 Kbits; forgreater traffic demands it is possible to use a pluralityof segments with a spatial capacity, placing them inparallel. 013002 16

Taking into considération that the network AT must formaprivate téléphoné network, in practice it is possible tostructure a hierarchical level, which, in a nationalreference network node, has access to the outside world; inthis case, the access to the outside world guarantees thepossibility that a user of the network AT can reach a userwho is not connected to the network AT, and thus, a clientof another telephony operator.

Starting from the national reference network node, astructure on a plurality of hierarchical levels isproduced, which can reach the individual user of thenetwork AT in every geographical area of differentcountries.

At the level of the national reference node, in addition,there is control of the connections between the régionalnodes of the network AT, as well as control of thetéléphoné charges; the connection between the nationalreference node and the régional nodes is provided by meansof a satellite network VSAT, or more generally by means ofa satellite network which opérâtes digitally, and ispreferably of the geostationary type.

The régional node of the network AT guarantees the connection between the various local résident nodes locatedin the région; at this level, transit takes place of ailthe calls between users of the network AT, which aredirected to local résident areas in the sanie région, otherthan the local résident area of origin, or those which aredirected to other régions or to other téléphoné operators.

The connection between the régional node and the localrésident nodes is always produced digitally, by means ofbidirectional satellite radio transmission, or, if this isnot possible, by means of communication via optical fibres. 013002 17 A régional router routes the communications between thevarious local residents' networks RLC, or créâtes theconnection with the other régional networks by means of thesatellite network VSAT; ail the signais are of the digitaltype.

The local residents' network, which is indicated as RLC infigure 3, assures the téléphoné connections or callsbetween users of the network AT in the same town, which arecontrolled locally by means of the structure schematised infigure 4.

Each town is subdivided into geographical areas withvariable dimensions, with a maximum radius of approximately3 Km, known as "sub-local résident areas"; each individual"sub-local résident" area is in fact a local point ofaccess AL, ALI to the network AT in IP protocol, since, infact, it is at this level that the standard telephony callsare transformed into IP protocol telephony.

Each individual area is provided with a conversion andcompression device GV, which guarantees the access andinitial routing on the network AT; taking intoconsidération the compression properties of the gatewaydevices GV, it is possible to connect to each access nodeAL, ALI, up to 300 simultaneous standard vocal téléphonéconnections or data connections, each of which is up to2 Mbits.

The connection between the access node AL, ALI and thestandard telephony Systems (of the PABX type) is providedby means of bidirectional satellite radio bridges or viaoptical fibres.

In order to assure the connection between the access nodesAL, ALI, each access node AL, ALI is provided with a 013002 18 routing device; in addition, an access node AL, ALI alsoprovides the connectivity with the régional node, in orderto permit the connection between the individual localresidents' networks.

The physical connection between the various access nodesAL, ALI, is provided with bidirectional satellite digitalradio bridges or on optical fibres, whereas the networktopology must be designed locally in order to minimise thecosts, whilst maximising the local résident cover.

Finally, the use of the routing devices assures redundancyof the network structures.

The description provided makes apparent the characteristicsand advantages of the télécommunications and telephonynetwork which is the subject of the présent invention.

To summarise, these consist of: - scalability, i.e. enlargement of the radio band, simplyby adding one or a plurality of bidirectional satelliteradio bridges and the corresponding antenna System, onevery site where this is necessary; -very low volume of power emitted by the radio Systems,which can thus also be self-supplied by means of solarpanels; -increased services offered on a single physical carrier,in comparison with conventional télécommunications Systems;-ease and speed of installation, and hi’gh level of économieviability in production and use; -possibility of transporting any digital signal, and ofcarrying out A/D and D/A conversions; -possibility of compressing the téléphoné signal, withconséquent optimisation of the network resources; -complété control of the network from a single location ornational node; -complété intégration between fixed telephony and mobile 013002 19 telephony; - simplicity in implémentation of the connection betweenthe Radio Base Station (TBS or RBS) and Control Station(DXT or BSC), which éliminâtes the difficulties caused bylaying cables for implémentation of the flows at 2 Mbit/s; - possibility of using simply and quickly Radio BaseStations (TBS or RBS) to be located at the appropriate timein places where there is an immédiate need for cover, suchas putting into service a Radio Station in order toincrease the number of carriers in the event of festivals,conventions, etc., and possibility of providing cover bymeans of transportable Radio Stations in locations whichhâve sustained disasters of any type; and -simple interfaceability of the System with the pre-existing Systems.

Finally, it is apparent that many variants can be made tothe télécommunications and telephony network in question,without departing from the principles of novelty which areinhérent in the inventive concept, and it is also apparentthat, in the practical implémentation of the invention, thedetails illustrated can be used in any form, according torequirements, and can be replaced by others which aretechnically équivalent.

Claims (5)

1. 013002 20 CLAIMS

   1. Télécommunications and telephony -network (AT) for controlling mobile (TC) or fixed peripheral devices at a customer premises, of the type comprising at least one local area network, at least one local residents' network (RLC), at least one régional network, at least one national network and a central network, said télécommunications and telephony network (AT) heing provided for deliveringsignais and data between a plurality of local accesses (AL,ALI), including local users (UL), and a plurality ofnetworks accesses (AG), through local exchanges (CL, CR), each of said local exchanges (CL, CR) including a multi-protocol gateway device (GV) for video and audio signaisand data compression and conversion into IP packets bearingIP telephony data flow or data flow from the Internet and alocal routing device (R) for routing said IP telephony data flow or data flow from the Internet, wherein said local users (UL) of each local access (AL, ALI) are connected to local centralising devices (MD) through first linking means(CO) for flowing data and signais, and said localcentralising devices (MD) are in turn connected to saidlocal exchanges (CL, CR) through second linking means (Cl,C4) for flowing data and signais, while said localexchanges (CL, CR) are connected to said networks accesses(AG) through third linking means (C2, C41) for flowing data 013002 21 and signais, characterised in that at least said second (Cl, C4) and - said third linking -means (C2, C41) are constituted by bidirectional satellite radio bridges (RLD, ST) .
2. 2. Télécommunications and telephony network (AT) as claimed in daim 1, characterised in that said first linking means(CO) are constituted by physical cables, such as téléphoné twisted pairs or optical fibers.
3. 3. Télécommunications and telephony network (AT) as claimed 10 in claim 1, characterised in that said local routingdevices (R) are connected to satellite routing devices (RS)or to radio bridges (PR) , said radio bridges (PR) beingable to provide connection between local residents' networks (RLC).
4. 4. Télécommunications and telephony network (AT) as claimed in claim 1, characterised in that each national network is connected to the relative régional network by means of a digital geostationary satellite network.
5. 5. Télécommunications and telephony network (AT) as claimed 20 in claim 1, characterised in that each régional network isconnected to the relative local residents' network (RLC) bymeans of a digital bidirectional satellite radiotransmission or by means of communication via optical fibres.