79:
979:). An A3/A8 algorithm is implemented in Subscriber Identity Module (SIM) cards and in GSM network Authentication Centers. It is used to authenticate the customer and generate a key for encrypting voice and data traffic, as defined in 3GPP TS 43.020 (03.20 before Rel-4). Development of A3 and A8 algorithms is considered a matter for individual GSM network operators, although example implementations are available. To encrypt Global System for Mobile Communications (GSM) cellular communications A5 algorithm is used.
1017:, or collected from the MS. In practice, for performance reasons, most vendors integrate the VLR directly to the V-MSC and, where this is not done, the VLR is very tightly linked with the MSC via a proprietary interface. Whenever an MSC detects a new MS in its network, in addition to creating a new record in the VLR, it also updates the HLR of the mobile subscriber, apprising it of the new location of that MS. If VLR data is corrupted it can lead to serious issues with text messaging and call services.
2309:
395:(G-MSC) is the MSC that determines which "visited MSC" (V-MSC) the subscriber who is being called is currently located at. It also interfaces with the PSTN. All mobile to mobile calls and PSTN to mobile calls are routed through a G-MSC. The term is only valid in the context of one call, since any MSC may provide both the gateway function and the visited MSC function. However, some manufacturers design dedicated high capacity MSCs which do not have any
149:
38:
2298:
1123:
country, which obliges all cellular operators of the country to do so. Therefore, in the delivery of the basic components of the network switching subsystem (core network) is often already present EIR with basic functionality, which includes a ‘whitelisted’ response to all CheckIMEI and the ability to fill IMEI blacklist, which will be given a ‘blacklisted’ response.
1179:
allowed to register the device. To do this, there are blocked all services, except the following: calls to a specific service number, sending SMS to a specific service number, and all
Internet traffic is redirected to a specific landing page. This is achieved by the fact that EIR can send commands to several MNO systems (HLR,
1262:
According to U.S. law, which has also been copied into many other countries, especially in Europe, all telecommunications equipment must provide facilities for monitoring the calls of selected users. There must be some level of support for this built into any of the different elements. The concept of
1122:
Most often, EIR uses the IMEI blacklist feature, which contains the IMEI of the devices that need to be banned from the network. As a rule, these are stolen or lost devices. Mobile operators rarely use EIR capabilities to block devices on their own. Usually blocking begins when there is a law in the
1073:
To purge the subscriber record if a subscriber becomes inactive whilst in the area of a VLR. The VLR deletes the subscriber's data after a fixed time period of inactivity and informs the HLR (e.g., when the phone has been switched off and left off or when the subscriber has moved to an area with no
1118:
The switching equipment must use the EIR response to determine whether or not to allow the device to register or re-register on the network. Since the response of switching equipment to ‘greylisted’ and ‘unknown equipment’ responses is not clearly described in the standard, they are most often not
774:
If the authentication fails, then no services are possible from that particular combination of SIM card and mobile phone operator attempted. There is an additional form of identification check performed on the serial number of the mobile phone described in the EIR section below, but this is not
1178:
Other functions may be required in individual cases. For example, Kazakhstan has introduced mandatory registration of devices and their binding to subscribers. But when a subscriber appears in the network with a new device, the network operation is not blocked completely, and the subscriber is
375:
In the GSM mobile phone system, in contrast with earlier analogue services, fax and data information is sent digitally encoded directly to the MSC. Only at the MSC is this re-coded into an "analogue" signal (although actually this will almost certainly mean sound is encoded digitally as a
940:(which is burned onto the SIM) into the A3 algorithm as appropriate and an SRES is calculated and sent back to the MSC. If this SRES matches with the SRES in the triplet (which it should if it is a valid SIM), then the mobile is allowed to attach and proceed with GSM services.
1130:) system, which is integrated with the EIR of all operators and transmits to them the actual lists of identifiers that must be used when processing CheckIMEI requests. In doing so, there may be many new requirements for EIR systems that are not present in the legacy EIR:
720:
Manage the mobility of subscribers by means of updating their position in administrative areas called 'location areas', which are identified with a LAC. The action of a user of moving from one LA to another is followed by the HLR with a
Location area update
456:
within the area that it serves. The functionality enables split control between (signaling ) and user plane (bearer in network element called as media gateway/MG), which guarantees better placement of network elements within the network.
971:
The AuC is usually collocated with the HLR, although this is not necessary. Whilst the procedure is secure for most everyday use, it is by no means hack proof. Therefore, a new set of security methods was designed for 3G phones.
636:
used by mobile phones to make and receive calls. The primary MSISDN is the number used for making and receiving voice calls and SMS, but it is possible for a SIM to have other secondary MSISDNs associated with it for
451:
is a soft-switch variant (therefore it may be referred to as mobile soft switch, MSS) of the mobile switching center, which provides circuit-switched calling mobility management, and GSM services to the mobile phones
387:
There are various different names for MSCs in different contexts which reflects their complex role in the network, all of these terms though could refer to the same MSC, but doing different things at different times.
837:
The MSC which requests a new batch of triplet data for an IMSI after the previous data have been used. This ensures that same keys and challenge responses are not used twice for a particular mobile.
1210:
is responsible for processing the toll tickets generated by the VLRs and HLRs and generating a bill for each subscriber. It is also responsible for generating billing data of roaming subscriber.
1271:. Generally, lawful Interception implementation is similar to the implementation of conference call. While A and B are talking with each other, C can join the call and listen silently.
610:(HLR) is a central database that contains details of each mobile phone subscriber that is authorized to use the GSM core network. There can be several logical, and physical, HLRs per
1362:
1126:
When the legislative framework for blocking registration of devices in cellular networks appears in the country, the telecommunications regulator usually has a
Central EIR (
1904:
1268:
108:
1190:
The most common suppliers of individual EIR systems (not as part of a complex solution) are the companies BroadForward, Mahindra
Comviva, Mavenir, Nokia, Eastwind.
767:
core network (typically when the phone is powered on). Once the authentication is successful, the HLR is allowed to manage the SIM and services described above. An
2152:
2164:
1724:
166:
51:
1451:
2337:
1925:
771:
is also generated that is subsequently used to encrypt all wireless communications (voice, SMS, etc.) between the mobile phone and the GSM core network.
716:
The main function of the HLR is to manage the fact that SIMs and phones move around a lot. The following procedures are implemented to deal with this:
1355:
1145:
1024:
615:
1134:
Synchronizing lists with CEIR. CEIR systems are not described by a standard, so the protocols and exchange mode may differ from country to country.
1090:
2232:
815:
1681:
679:
transactions and messages from elements in the GSM network, for example, the location update messages received as mobile phones roam around.
2137:
1578:
213:
1769:
1348:
1127:
185:
2147:
1180:
309:(PSTN). The architecture contains specific features and functions which are needed because the phones are not fixed in one location.
1836:
1485:
1406:
306:
250:
232:
130:
65:
372:, handles mobility and hand-over requirements during the call and takes care of charging and real-time prepaid account monitoring.
192:
1848:
1431:
1381:
57:
2237:
1841:
1411:
475:(CS) used here originates from traditional telecommunications systems. However, modern MSS and MGW devices mostly use generic
2183:
442:
426:
199:
170:
863:
When the MSC asks the AuC for a new set of triplets for a particular IMSI, the AuC first generates a random number known as
929:) form the triplet sent back to the MSC. When a particular IMSI requests access to the GSM core network, the MSC sends the
2176:
2159:
333:
1008:
may be served by many MSCs in case of MSC in pool), hence a subscriber cannot be present in more than one VLR at a time.
1676:
1622:
1597:
1480:
1471:
1220:
1184:
655:
578:
337:
181:
91:
1637:
101:
95:
87:
1098:
611:
508:
465:
618:(IMSI)/MSISDN pair can be associated with only one logical HLR (which can span several physical nodes) at a time.
159:
1632:
112:
2302:
2132:
1894:
1888:
1882:
1831:
1799:
1401:
1005:
1001:
954:(BSC) so that all communications can be encrypted and decrypted. Of course, the mobile phone can generate the
645:
to the HLR record. The HLR data is stored for as long as a subscriber remains with the mobile phone operator.
2252:
1860:
1501:
676:
591:
480:
2277:
1389:
1283:
951:
859:
Algorithm id. (the standard algorithms are called A3 or A8, but an operator may choose a proprietary one).
519:
464:(MGW) makes it possible to cross-connect circuit-switched calls switched by using IP, ATM AAL2 as well as
396:
365:
voice calls and SMS as well as other services (such as conference calls, FAX, and circuit-switched data).
328:
calls. It was extended with an overlay architecture to provide packet-switched data services known as the
294:
1426:
1000:) that have roamed into the jurisdiction of the Mobile Switching Center (MSC) which it serves. Each main
778:
Proper implementation of security in and around the AuC is a key part of an operator's strategy to avoid
206:
2332:
2215:
2142:
1568:
1077:
To delete the subscriber record when a subscriber explicitly moves to another, as instructed by the HLR.
1039:
377:
325:
321:
298:
807:
is securely burned into the SIM during manufacture and is also securely replicated onto the AuC. This
2220:
2205:
2195:
1421:
1416:
1138:
737:
Responsible for all SRI related queries (i.e. for invoke SRI, HLR should give sack SRI or SRI reply).
785:
The AuC does not engage directly in the authentication process, but instead generates data known as
399:(BSS) connected to them. These MSCs will then be the gateway MSC for many of the calls they handle.
2272:
2210:
2200:
2190:
1257:
362:
283:
625:
issued by the mobile phone operator. Each SIM has a unique identifier called an IMSI which is the
279:
2313:
472:
329:
2102:
2076:
1064:
To track where the subscriber is within the VLR area (location area) when no call is ongoing.
2227:
2127:
2122:
1999:
1441:
1371:
633:
1293:
2171:
1334:
1313:
Shahabuddin, Shahria; Rahaman, Sadiqur; Rehman, Faisal; Ahmad, Ijaz; Khan, Zaheer (2018).
1061:
To inform the HLR that a subscriber has arrived in the particular area covered by the VLR.
975:
In practice, A3 and A8 algorithms are generally implemented together (known as A3/A8, see
668:
488:
484:
17:
814:
is never transmitted between the AuC and SIM, but is combined with the IMSI to produce a
2262:
2257:
2086:
1392:
997:
768:
756:
734:
Remove subscriber data from the previous VLR when a subscriber has roamed away from it.
632:
Another important item of data associated with the SIM are the MSISDNs, which are the
548:(VLR) provides subscriber information when the subscriber is outside its home network.
2326:
2267:
790:
789:
for the MSC to use during the procedure. The security of the process depends upon a
461:
287:
727:
Broker between the G-MSC or SMSC and the subscriber's current VLR in order to allow
2242:
1989:
1973:
1606:
728:
568:
317:
313:
1198:
Connected more or less directly to the GSM core network are many other functions.
1137:
Supporting additional lists – IMEI white list, IMEI grey list, list of allocated
704:
system for delivering notifications to the mobile phone that a message is waiting
2071:
2020:
1930:
1918:
1144:
Support in lists not only IMEI but also bindings – IMEI-IMSI, IMEI-MSISDN, IMEI-
779:
626:
148:
724:
Send the subscriber data to a VLR or SGSN when a subscriber first roams there.
701:
642:
1340:
1243:
302:
1093:(checkIMEI) of mobile devices that come from the switching equipment (MSC,
893:
are fed into the A3 algorithm and the signed response (SRES) is calculated.
1111:
greylisted – the device is allowed to register on the network temporarily.
2050:
1954:
1853:
1776:
1743:
1703:
1697:
760:
694:
The VLR for handling requests from mobile phones to attach to the network
622:
476:
418:
361:(MSC) is the primary service delivery node for GSM/CDMA, responsible for
341:
707:
The AuC for authentication and ciphering and exchange of data (triplets)
2284:
1781:
1587:
1521:
1516:
1436:
1288:
1108:
blacklisted – the device is prohibited from registering on the network.
976:
961:
itself by feeding the same RAND supplied during authentication and the
933:
part of the triplet to the SIM. The SIM then feeds this number and the
552:
453:
290:
410:(VLR) associated with this MSC will have the subscriber's data in it.
1993:
1864:
1764:
1506:
1446:
1149:
512:
1171:
Accumulating the subscribers’ profiles (history of device changing).
1070:
To allocate roaming numbers during the processing of incoming calls.
648:
Examples of other data stored in the HLR against an IMSI record is:
1168:
Integration with the billing system to receive IMSI-MSISDN bundles.
2081:
2066:
2029:
2016:
1935:
1913:
1719:
1511:
1230:
1226:
943:
After successful authentication, the MSC sends the encryption key
658:(GPRS) settings to allow the subscriber to access packet services.
574:
Connecting outgoing calls to other mobile subscribers or the PSTN.
534:
2247:
1945:
1759:
1627:
1554:
1094:
662:
527:
430:
1344:
1105:
whitelisted – the device is allowed to register on the network.
332:. This allows mobile phones to have access to services such as
1667:
1642:
1563:
1550:
1526:
1162:
638:
406:(V-MSC) is the MSC where a customer is currently located. The
381:
275:
142:
72:
31:
27:
1011:
The data stored in the VLR has either been received from the
652:
GSM services that the subscriber has requested or been given.
301:
and allows mobile devices to communicate with each other and
2045:
1968:
1814:
1738:
1656:
1540:
1461:
1225:
supports the sending of multimedia messages (e.g., images,
1067:
To allow or disallow which services the subscriber may use.
538:
523:
1174:
Long-term storage of processing of all CheckIMEI requests.
1158:
Automatic adding the item to a list in separate scenarios.
675:
The HLR is a system which directly receives and processes
1089:
is a system that handles real-time requests to check the
818:
for identification purposes and an encryption key called
1335:
437:
Mobile switching center server (MSC-Server, MSCS or MSS)
425:
is the MSC toward which a handover should take place. A
907:
are fed into the A8 algorithm and a session key called
1036:
GSM services that the subscriber is allowed to access.
429:
is a part of the redesigned MSC concept starting from
1012:
312:
The NSS originally consisted of the circuit-switched
1233:
and their combinations) to (or from) MMS-bluetooth.
829:
Other GSM core network elements connected to the AuC
683:
Other GSM core network elements connected to the HLR
545:
495:
Other GSM core network elements connected to the MSC
407:
2115:
2095:
2059:
2044:
2009:
1982:
1967:
1944:
1903:
1874:
1824:
1813:
1792:
1752:
1737:
1712:
1690:
1666:
1655:
1615:
1596:
1577:
1549:
1539:
1494:
1470:
1460:
1388:
1267:is also known, following the relevant U.S. law, as
1165:
notifications to subscribers in separate scenarios.
537:(UTRAN) which handles the radio communication with
468:. More information is available in 3GPP TS 23.205.
173:. Unsourced material may be challenged and removed.
1155:Supporting the customized logic of lists applying.
1114:An error ‘unknown equipment’ may also be returned.
1331:4GLET - the standardisation body for GSM and UMTS
1004:in the network is served by exactly one VLR (one
846:The AuC stores the following data for each IMSI:
571:as they arrive based on information from the VLR.
522:(BSS) which handles the radio communication with
504:
380:(PCM) signal in a 64-kbit/s timeslot, known as a
1101:). The answer contains the result of the check:
587:Carrying out handovers from this MSC to another.
100:but its sources remain unclear because it lacks
729:incoming calls or text messages to be delivered
671:settings applicable for each associated MSISDN.
483:. MSS software may run on generic computers or
1356:
8:
833:The AuC connects to the following elements:
687:The HLR connects to the following elements:
515:number (MSISDN; i.e., the telephone number).
499:The MSC connects to the following elements:
66:Learn how and when to remove these messages
2056:
1979:
1821:
1749:
1663:
1546:
1467:
1363:
1349:
1341:
1214:Multimedia messaging service center (MMSC)
481:next-generation telecommunication networks
251:Learn how and when to remove this message
233:Learn how and when to remove this message
131:Learn how and when to remove this message
1317:. John Wiley & Sons Ltd. p. 12.
825:for use in over the air communications.
661:Current location of subscriber (VLR and
616:international mobile subscriber identity
577:Delivering SMSs from subscribers to the
1305:
1033:MSISDN (the subscriber's phone number).
793:between the AuC and the SIM called the
2233:Multimedia Broadcast Multicast Service
1057:The primary functions of the VLR are:
641:and data calls. Each MSISDN is also a
594:such as conference calls or call hold.
691:The G-MSC for handling incoming calls
535:UMTS terrestrial radio access network
7:
2191:Spectral efficiency comparison table
1315:A Comprehensive Guide to 5G Security
1048:SCP Address(For Prepaid Subscriber).
584:Arranging handovers from BSC to BSC.
171:adding citations to reliable sources
1027:(the subscriber's identity number).
878:to produce two numbers as follows:
697:The SMSC for handling incoming SMSs
507:(HLR) for obtaining data about the
1045:The HLR address of the subscriber.
551:Other MSCs for procedures such as
25:
2338:Telecommunications infrastructure
1082:Equipment identity register (EIR)
368:The MSC sets up and releases the
307:public switched telephone network
47:This article has multiple issues.
2307:
2296:
1382:List of mobile phone generations
775:relevant to the AuC processing.
763:that attempts to connect to the
621:The HLRs store details of every
147:
77:
36:
994:Visitor Location Register (VLR)
983:Visitor location register (VLR)
597:Generating billing information.
569:Delivering calls to subscribers
158:needs additional citations for
55:or discuss these issues on the
1248:records and stores voicemail.
449:mobile switching center server
443:Mobile switching centre server
427:mobile switching center server
297:. It is owned and deployed by
1:
1337:- a PDF eBook by Gunnar Heine
1252:Lawful interception functions
602:Home location register (HLR)
348:Mobile switching center (MSC)
182:"Network switching subsystem"
2303:Telecommunication portal
1221:multimedia messaging service
1014:Home Location Register (HLR)
656:General Packet Radio Service
579:short message service center
742:Authentication center (AuC)
264:Network switching subsystem
2354:
1800:CDMA2000 1xEV-DO Release 0
1255:
1074:coverage for a long time).
996:is a database of the MSs (
871:is then combined with the
612:public land mobile network
564:Tasks of the MSC include:
440:
18:Visitor Location Registers
2293:
1682:EDGE/EGPRS - Evolved EDGE
1607:D-AMPS (IS-54 and IS-136)
1379:
663:serving GPRS support node
546:visitor location register
408:visitor location register
1002:base transceiver station
421:has been initiated. The
417:is the MSC from which a
295:network of base stations
278:system that carries out
274:) is the component of a
86:This article includes a
2138:Comparison of standards
1777:UTRA-TDD LCR / TD-SCDMA
1194:Other support functions
1020:Data stored include:
968:into the A8 algorithm.
952:base station controller
755:(AuC) is a function to
520:base station subsystems
397:base station subsystems
359:mobile switching center
316:, used for traditional
115:more precise citations.
2143:Channel access methods
1782:UTRA-TDD HCR / TD-CDMA
1284:Base station subsystem
1237:Voicemail system (VMS)
1053:Procedures implemented
842:Procedures implemented
712:Procedures implemented
608:home location register
592:supplementary services
581:(SMSC) and vice versa.
560:Procedures implemented
505:home location register
479:technologies and form
299:mobile phone operators
2314:Telephones portal
1422:MTA - MTB - MTC - MTD
1280:The GSM core network.
753:authentication center
378:pulse-code modulation
370:end-to-end connection
326:circuit switched data
320:such as voice calls,
1931:iBurst (IEEE 802.20)
1704:CDMA2000 1X Advanced
1030:Authentication data.
629:to each HLR record.
513:mobile services ISDN
167:improve this article
1817:(3.5G, 3.75G, 3.9G)
1659:(2.5G, 2.75G, 2.9G)
1427:Mobile TeleSeratout
1265:lawful interception
1258:Lawful interception
1202:Billing center (BC)
1040:access point (GPRS)
614:(PLMN), though one
284:mobility management
2305:
1891:(TIA/EIA/IS-856-B)
1885:(TIA/EIA/IS-856-A)
1883:1xEV-DO Revision A
816:challenge/response
88:list of references
2320:
2319:
2123:Cellular networks
2111:
2110:
2040:
2039:
1963:
1962:
1809:
1808:
1765:UTRA-FDD / W-CDMA
1733:
1732:
1700:(TIA/EIA/IS-2000)
1651:
1650:
1535:
1534:
634:telephone numbers
473:Circuit switching
330:GPRS core network
261:
260:
253:
243:
242:
235:
217:
141:
140:
133:
70:
16:(Redirected from
2345:
2312:
2311:
2310:
2301:
2300:
2299:
2228:Mobile broadband
2128:Mobile telephony
2116:Related articles
2057:
2000:LTE Advanced Pro
1980:
1895:EV-DO Revision C
1889:EV-DO Revision B
1822:
1750:
1664:
1547:
1468:
1393:radio telephones
1372:Cellular network
1365:
1358:
1351:
1342:
1319:
1318:
1310:
485:virtual machines
272:GSM core network
256:
249:
238:
231:
227:
224:
218:
216:
175:
151:
143:
136:
129:
125:
122:
116:
111:this article by
102:inline citations
81:
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62:
40:
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32:
21:
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2342:
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2321:
2316:
2308:
2306:
2297:
2295:
2289:
2196:Frequency bands
2107:
2091:
2049:
2036:
2005:
1972:
1959:
1940:
1899:
1870:
1816:
1815:3G transitional
1805:
1788:
1742:
1729:
1708:
1686:
1658:
1657:2G transitional
1647:
1611:
1592:
1588:cdmaOne (IS-95)
1573:
1531:
1490:
1456:
1384:
1375:
1369:
1328:
1323:
1322:
1312:
1311:
1307:
1302:
1277:
1260:
1254:
1239:
1216:
1204:
1196:
1084:
1055:
998:Mobile stations
990:
985:
966:
959:
948:
938:
927:
912:
901:
887:
876:
855:
844:
831:
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714:
685:
604:
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176:
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152:
137:
126:
120:
117:
106:
92:related reading
82:
78:
41:
37:
28:
23:
22:
15:
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11:
5:
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2109:
2108:
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2105:
2099:
2097:
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2089:
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2079:
2074:
2069:
2063:
2061:
2054:
2042:
2041:
2038:
2037:
2035:
2034:
2033:
2032:
2027:
2013:
2011:
2007:
2006:
2004:
2003:
1997:
1986:
1984:
1977:
1965:
1964:
1961:
1960:
1958:
1957:
1951:
1949:
1942:
1941:
1939:
1938:
1933:
1928:
1923:
1922:
1921:
1910:
1908:
1901:
1900:
1898:
1897:
1892:
1886:
1878:
1876:
1872:
1871:
1869:
1868:
1858:
1857:
1856:
1846:
1845:
1844:
1839:
1828:
1826:
1819:
1811:
1810:
1807:
1806:
1804:
1803:
1796:
1794:
1790:
1789:
1787:
1786:
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1784:
1779:
1774:
1773:
1772:
1756:
1754:
1747:
1735:
1734:
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1728:
1727:
1722:
1716:
1714:
1710:
1709:
1707:
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1694:
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1688:
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1679:
1673:
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1640:
1635:
1630:
1625:
1619:
1617:
1613:
1612:
1610:
1609:
1603:
1601:
1594:
1593:
1591:
1590:
1584:
1582:
1575:
1574:
1572:
1571:
1566:
1560:
1558:
1544:
1537:
1536:
1533:
1532:
1530:
1529:
1524:
1519:
1514:
1509:
1504:
1498:
1496:
1492:
1491:
1489:
1488:
1483:
1477:
1475:
1465:
1458:
1457:
1455:
1454:
1449:
1444:
1439:
1437:Autotel (PALM)
1434:
1429:
1424:
1419:
1414:
1409:
1404:
1398:
1396:
1386:
1385:
1380:
1377:
1376:
1370:
1368:
1367:
1360:
1353:
1345:
1339:
1338:
1332:
1327:
1326:External links
1324:
1321:
1320:
1304:
1303:
1301:
1298:
1297:
1296:
1291:
1286:
1281:
1276:
1273:
1256:Main article:
1253:
1250:
1238:
1235:
1215:
1212:
1208:billing center
1203:
1200:
1195:
1192:
1176:
1175:
1172:
1169:
1166:
1159:
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1142:
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1065:
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1034:
1031:
1028:
989:
986:
984:
981:
964:
957:
946:
936:
925:
916:
915:
914:is calculated.
910:
899:
894:
885:
874:
861:
860:
857:
853:
843:
840:
839:
838:
830:
827:
821:
810:
803:
796:
769:encryption key
748:
745:
743:
740:
739:
738:
735:
732:
725:
722:
713:
710:
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684:
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673:
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659:
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588:
585:
582:
575:
572:
561:
558:
557:
556:
549:
542:
541:mobile phones.
531:
530:mobile phones.
516:
496:
493:
441:Main article:
438:
435:
431:3GPP Release 4
354:
351:
349:
346:
286:functions for
259:
258:
241:
240:
155:
153:
146:
139:
138:
96:external links
85:
83:
76:
71:
45:
44:
42:
35:
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
2350:
2339:
2336:
2334:
2331:
2330:
2328:
2315:
2304:
2292:
2286:
2283:
2279:
2278:Wi-Fi Calling
2276:
2274:
2271:
2269:
2266:
2264:
2261:
2259:
2256:
2255:
2254:
2251:
2249:
2246:
2244:
2241:
2239:
2238:NGMN Alliance
2236:
2234:
2231:
2229:
2226:
2222:
2219:
2217:
2214:
2212:
2209:
2207:
2204:
2202:
2199:
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2197:
2194:
2192:
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2185:
2182:
2178:
2175:
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2173:
2170:
2166:
2163:
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2161:
2158:
2154:
2151:
2150:
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2136:
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2126:
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2121:
2120:
2118:
2114:
2104:
2101:
2100:
2098:
2094:
2088:
2085:
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2078:
2075:
2073:
2070:
2068:
2065:
2064:
2062:
2058:
2055:
2052:
2047:
2043:
2031:
2028:
2025:
2024:
2022:
2018:
2015:
2014:
2012:
2008:
2001:
1998:
1995:
1991:
1988:
1987:
1985:
1981:
1978:
1975:
1970:
1966:
1956:
1953:
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1950:
1947:
1943:
1937:
1934:
1932:
1929:
1927:
1924:
1920:
1917:
1916:
1915:
1912:
1911:
1909:
1906:
1902:
1896:
1893:
1890:
1887:
1884:
1880:
1879:
1877:
1873:
1866:
1862:
1859:
1855:
1852:
1851:
1850:
1847:
1843:
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1838:
1835:
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1833:
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1827:
1823:
1820:
1818:
1812:
1801:
1798:
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1783:
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1775:
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1768:
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1766:
1763:
1762:
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1748:
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1736:
1726:
1723:
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1718:
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1715:
1711:
1705:
1702:
1699:
1696:
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1669:
1665:
1662:
1660:
1654:
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1621:
1620:
1618:
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1604:
1602:
1599:
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1589:
1586:
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1583:
1580:
1576:
1570:
1567:
1565:
1562:
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1559:
1556:
1552:
1548:
1545:
1542:
1538:
1528:
1525:
1523:
1520:
1518:
1515:
1513:
1510:
1508:
1505:
1503:
1500:
1499:
1497:
1493:
1487:
1484:
1482:
1481:AMPS - N-AMPS
1479:
1478:
1476:
1473:
1469:
1466:
1463:
1459:
1453:
1450:
1448:
1445:
1443:
1440:
1438:
1435:
1433:
1430:
1428:
1425:
1423:
1420:
1418:
1415:
1413:
1410:
1408:
1405:
1403:
1400:
1399:
1397:
1394:
1391:
1387:
1383:
1378:
1373:
1366:
1361:
1359:
1354:
1352:
1347:
1346:
1343:
1336:
1333:
1330:
1329:
1325:
1316:
1309:
1306:
1299:
1295:
1292:
1290:
1287:
1285:
1282:
1279:
1278:
1274:
1272:
1270:
1266:
1259:
1251:
1249:
1247:
1245:
1236:
1234:
1232:
1228:
1224:
1222:
1213:
1211:
1209:
1201:
1199:
1193:
1191:
1188:
1186:
1182:
1173:
1170:
1167:
1164:
1160:
1157:
1154:
1151:
1147:
1143:
1140:
1136:
1133:
1132:
1131:
1129:
1124:
1120:
1113:
1110:
1107:
1104:
1103:
1102:
1100:
1096:
1092:
1088:
1081:
1076:
1072:
1069:
1066:
1063:
1060:
1059:
1058:
1052:
1047:
1044:
1041:
1038:
1035:
1032:
1029:
1026:
1023:
1022:
1021:
1018:
1016:
1015:
1009:
1007:
1003:
999:
995:
987:
982:
980:
978:
973:
969:
967:
960:
953:
949:
941:
939:
932:
928:
921:
918:The numbers (
913:
906:
902:
895:
892:
888:
881:
880:
879:
877:
870:
866:
858:
856:
849:
848:
847:
841:
836:
835:
834:
828:
826:
824:
817:
813:
806:
799:
792:
791:shared secret
788:
783:
781:
776:
772:
770:
766:
762:
758:
754:
746:
741:
736:
733:
730:
726:
723:
719:
718:
717:
711:
706:
703:
699:
696:
693:
690:
689:
688:
682:
680:
678:
670:
667:
664:
660:
657:
654:
651:
650:
649:
646:
644:
640:
635:
630:
628:
624:
619:
617:
613:
609:
601:
596:
593:
589:
586:
583:
580:
576:
573:
570:
567:
566:
565:
559:
554:
550:
547:
543:
540:
536:
532:
529:
525:
521:
517:
514:
510:
506:
502:
501:
500:
494:
492:
491:environment.
490:
486:
482:
478:
474:
469:
467:
463:
462:media gateway
458:
455:
450:
444:
436:
434:
432:
428:
424:
420:
416:
411:
409:
405:
400:
398:
394:
389:
385:
384:in America).
383:
379:
373:
371:
366:
364:
360:
352:
347:
345:
343:
339:
335:
331:
327:
323:
319:
315:
310:
308:
305:in the wider
304:
300:
296:
292:
289:
288:mobile phones
285:
281:
277:
273:
269:
265:
255:
252:
237:
234:
226:
215:
212:
208:
205:
201:
198:
194:
191:
187:
184: –
183:
179:
178:Find sources:
172:
168:
162:
161:
156:This article
154:
150:
145:
144:
135:
132:
124:
114:
110:
104:
103:
97:
93:
89:
84:
75:
74:
69:
67:
60:
59:
54:
53:
48:
43:
34:
33:
30:
19:
2333:GSM standard
2243:Push-to-talk
2021:IEEE 802.16m
1990:LTE Advanced
1974:IMT Advanced
1919:IEEE 802.16e
1914:Mobile WiMAX
1875:3GPP2 family
1802:(TIA/IS-856)
1793:3GPP2 family
1691:3GPP2 family
1670:/3GPP family
1486:TACS - ETACS
1314:
1308:
1264:
1261:
1242:
1240:
1219:
1217:
1207:
1205:
1197:
1189:
1177:
1125:
1121:
1117:
1086:
1085:
1056:
1019:
1013:
1010:
993:
991:
974:
970:
962:
955:
944:
942:
934:
930:
923:
919:
917:
908:
904:
897:
890:
883:
872:
868:
864:
862:
851:
845:
832:
819:
808:
801:
794:
786:
784:
777:
773:
764:
757:authenticate
752:
750:
715:
686:
674:
647:
631:
620:
607:
605:
563:
498:
470:
459:
448:
446:
422:
414:
412:
403:
401:
392:
390:
386:
374:
369:
367:
358:
356:
318:GSM services
314:core network
311:
271:
267:
263:
262:
247:
229:
220:
210:
203:
196:
189:
177:
165:Please help
160:verification
157:
127:
118:
107:Please help
99:
63:
56:
50:
49:Please help
46:
29:
2072:5G-Advanced
2060:3GPP family
2010:IEEE family
2002:(4.5G/4.9G)
1983:3GPP family
1825:3GPP family
1753:3GPP family
1698:CDMA2000 1X
1569:CSD - HSCSD
1042:subscribed.
988:Description
780:SIM cloning
747:Description
669:Call divert
627:primary key
590:Supporting
404:visited MSC
393:gateway MSC
353:Description
113:introducing
2327:Categories
1926:Flash-OFDM
1300:References
721:procedure.
702:voice mail
643:unique key
423:target MSC
415:anchor MSC
303:telephones
223:March 2009
193:newspapers
121:March 2019
52:improve it
2026:WiMax 2.1
1881:CDMA2000
1374:standards
1244:voicemail
1187:, etc.).
553:hand over
471:The term
58:talk page
2051:IMT-2020
1955:HiperMAN
1854:DC-HSDPA
1744:IMT-2000
1275:See also
1161:Sending
922:, SRES,
787:triplets
761:SIM card
623:SIM card
477:Internet
460:MSS and
419:handover
342:Internet
340:and the
280:call out
2285:Osmocom
2133:History
2103:DECT-5G
2077:NR-IIoT
1522:DataTAC
1517:Mobitex
1289:COMP128
977:COMP128
950:to the
867:. This
665:/SGSN).
454:roaming
363:routing
293:on the
291:roaming
207:scholar
109:improve
2087:NB-IoT
2053:(2021)
2048:(2018)
1994:E-UTRA
1976:(2013)
1971:(2009)
1948:family
1907:family
1865:E-UTRA
1746:(2001)
1741:(1998)
1600:family
1581:family
1557:family
1543:(1991)
1474:family
1464:(1979)
1447:B-Netz
1395:(1946)
1246:system
1223:center
1150:MSISDN
1141:, etc.
1119:used.
800:. The
324:, and
270:) (or
209:
202:
195:
188:
180:
2263:ViLTE
2258:VoLTE
2216:5G NR
2165:STDMA
2153:OFDMA
2096:Other
2082:LTE-M
2067:5G NR
2030:WiBro
2017:WiMAX
1936:WiBro
1849:HSPA+
1842:HSUPA
1837:HSDPA
1720:WiDEN
1713:Other
1616:Other
1579:3GPP2
1512:Hicap
1507:C-450
1495:Other
1412:Altai
1294:4GLET
1269:CALEA
1231:video
1227:audio
759:each
489:cloud
214:JSTOR
200:books
94:, or
2273:ViNR
2268:VoNR
2248:MIMO
2221:CDMA
2206:UMTS
2184:SDMA
2177:CDMA
2172:SSMA
2160:TDMA
2148:FDMA
1946:ETSI
1905:IEEE
1832:HSPA
1770:FOMA
1760:UMTS
1725:DECT
1677:GPRS
1628:iDEN
1623:CDPD
1598:AMPS
1555:3GPP
1472:AMPS
1432:AMTS
1407:IMTS
1241:The
1218:The
1206:The
1185:SMSC
1181:PCRF
1146:IMSI
1139:TACs
1128:CEIR
1095:SGSN
1091:IMEI
1025:IMSI
992:The
931:RAND
920:RAND
905:RAND
903:and
896:The
891:RAND
889:and
882:The
869:RAND
865:RAND
850:the
751:The
700:The
606:The
544:The
533:The
528:2.5G
526:and
518:The
511:and
503:The
447:The
413:The
402:The
391:The
357:The
282:and
186:news
2253:IMS
2211:LTE
2201:GSM
1861:LTE
1668:GSM
1643:CT2
1638:PHS
1633:PDC
1564:GSM
1551:GSM
1527:CT1
1502:NMT
1452:AMR
1442:ARP
1417:OLT
1402:MTS
1163:SMS
1099:MME
1087:EIR
1006:BTS
765:gsm
677:MAP
639:fax
509:SIM
487:in
466:TDM
382:DS0
338:MMS
334:WAP
322:SMS
276:GSM
268:NSS
169:by
2329::
2046:5G
2023:)
1969:4G
1739:3G
1541:2G
1462:1G
1390:0G
1229:,
1183:,
1097:,
782:.
539:3G
524:2G
433:.
344:.
336:,
98:,
90:,
61:.
2019:(
1996:)
1992:(
1867:)
1863:(
1553:/
1364:e
1357:t
1350:v
1152:.
1148:-
965:i
963:K
958:c
956:K
947:c
945:K
937:i
935:K
926:c
924:K
911:c
909:K
900:i
898:K
886:i
884:K
875:i
873:K
854:i
852:K
822:c
820:K
811:i
809:K
804:i
802:K
797:i
795:K
731:.
555:.
266:(
254:)
248:(
236:)
230:(
225:)
221:(
211:·
204:·
197:·
190:·
163:.
134:)
128:(
123:)
119:(
105:.
68:)
64:(
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
