2G / 3G / 4G / IMS / 5G Overview with Focus on Core Network

- A good document for a basic knowledge in Mobile Networks.
- A Presentation by Hamidreza Bolhasani

1. Mobile Networks Overview 2G/3G/4G/5G with Focus on Core Network Hamidreza Bolhasani Ph.D., AI/Data Scientist [email protected] Dec 2020.

2. Self Introduction Mobile Networks History GSM Overview and concepts 2G/3G Network Elements and Protocols Basic CS Scenarios Overview PS / GPRS / EDGE Introduction 4G/LTE Network Architecture and services PS / EPC Scenarios Review Introduction to 5G and its Services Conclusion - Q & A T able of Contents

3. S elf I ntroduction

4. M obile N etworks H istory

5. M obile N etworks H istory

6. G lobal S ystem for M obiles (GSM) Cellular Network or Mobile Network is a communication network where the last link is wireless. The network is distributed over land areas called cells, each served by at least one fixed-location transceiver, known as a cell or base station.

7. 2 G / 3 G O verview GSM /GPRS BSS BTS BSC NodeB RNC PCU UTRAN SCP SMS SCE PSTN ISDN Internet, Intranet MSC/VLR GMSC HLR/AUC SGSN CG BG GGSN GPRS RAN CN Other PLMN IPBB

8. 2 G R adio BTS (Base Station Transceiver) BTS is a piece of equipment that facilitates wireless communication between user equipment (UE) and a network. UEs are devices like mobile phones (handsets), WLL phones, computers with wireless Internet connectivity. BSC (Base Station Controller) BSC is a critical mobile network component that controls one or more base transceiver stations (BTS), also known as base stations or cell sites. Key BSC functions include radio network management (such as radio frequency control), BTS handover management and call setup. It also carries transcoding of speech channels.

9. G SM F requency B ands

10. I SM B ands

11. 3 G R adio NodeB NodeB is a term used in UMTS equivalent to the BTS (base transceiver station) description used in GSM. RNC (Radio Network Controller) RNC is a governing element in the UMTS radio access network (UTRAN) and is responsible for controlling the NodeBs that are connected to it. The RNC carries out radio resource management, some of the mobility management functions and is the point where encryption is done before user data is sent to and from the mobile.

12. T erminologies - I MSI MCC MNC MSIN 3 digits 2/3 digits Not more than 15 digits IMSI (International Mobile Subscriber Identity) NMSI MCC ： Mobile Country Code MNC ： Mobile Network Code MSIN ： Mobile Station Identification Number NMSI ： National Mobile Station Identity

13. I MSI IMSI: International Mobile Subscriber Identity IMSI is a unique identifier allocated to each mobile subscriber Its code type is E.212 IMSI can be saved in SIM, HLR and VLR and can be transferred through MAP and Wireless interface. IMSI has almost 15 digits (0-9) such as 43211xxxxxxxxxx

14. T MSI TMSI: Temporary Mobile Subscriber Identity In order to ensure subscriber identity confidentiality, the VLR (Visiting Location Register) and SGSN (Serving GPRS Support Node) may allocate TMSI to visiting mobile subscribers.

15. I MEI TAC FAC spare 6 digits 2 digits 15 digits IMEI (International Mobile Equipment Identity) TAC ： Type Approval Code FAC ： Final Assembly Code SNR ： Serial Number spare ： Standby bit Example:490547403767335 SNR 6 digits 1 digits

16. M SISDN CC NDC SN National ( Significant ) Mobile Number MSISDN ： Mobile Station International ISDN number CC： Country Code , China Country Code is 8 6 NDC：National Destination Code SN： Subscriber Number

17. L AI / G CI / S AI Location Area Identity MCC MNC LAC Cell Global Identity MCC MNC LAC CI Service Area Identity MCC MNC LAC SAC

18. T AI / T AC Tracking Area Identity MCC MNC TAC

19. 2 G / 3 G C ore Network (CN) Core Network is split into CS domain and PS domain . CS domain is based on original GSM network. PS domain is based on original GPRS network. CS domain : used to provide Circuit-switched service. Network mode can support TDM, ATM and IP. Physical entities include switching equipment (such as MSC/VLR, GMSCs, HSS), and inter-working equipment (IWF). PS domain : used to provide Packet-switched service. Network mode is IP. Physical entities include SGSN, GGSN, CG , BG etc.

20. 2 G / 3 G C ore Network (CN) Function entity shared by CS domain and PS : MSC Server : Control layer, to realize MM (Mobility Management), CM (Call Control), MGC (Media Gateway Control). MGW : Bearer layer, to realize the exchange of voice and media flow, and provide all kinds sources, such as TC, EC, play announcement and receive DTMF. SG : To realize signaling transfer from MTP (SS7 transmission layer) to SCTP/IP (SIGTRAN).

21. 2 G / 3 G C ore Network (CN) HLR/HSS : To realize mobile subscriber management and location information management. VLR : To deal with all kinds of data information of current mobile subscriber. AUC : To store authentication information of mobile subscriber. EIR : To store IMEI data of mobile subscriber. SMS : Short Message Center.

22. S cenario #1 L ocation U pdate

23. S cenario #1 L ocation U pdate / Authentication

24. S cenario #1 L ocation U pdate / Authentication A3 RAND K i 128 bit 128 bit SRES* 32 bit A3 RAND K i 128 bit 128 bit SRES 32 bit SRES* =? SRES SRES RAND SRES 32 bit mobile network SIM AC MSC SIM K i : individual subscriber authentication key SRES: signed response

25. S cenario #2 C all F low (1/2)

26. S cenario #2 C all F low (2/2)

27. S cenario #2 C all F low / Real (1/5)

28. S cenario #2 C all F low / Real (2/5)

29. S cenario #2 C all F low / Real (3/5)

30. S cenario #2 C all F low / Real (4/5)

31. S cenario #2 C all F low / Real (5/5)

32. S cenario #3 S MS M O

33. G PRS N etwork S tructure What is GPRS? General Packet Radio Service Why GPRS? In order to provide the data service out the scope of the fixed network GPRS network classification GSM GPRS UMTS GPRS GPRS network background GSM GPRS network reuse the existed GSM network UMTS GPRS network just change the RAN side

34. G PRS N etwork S tructure FR EIR HLR SMS-GMSC SMS-IWMSC MSC/VLR BSS UTRAN SGSN SGSN GGSN BG CG TE PDN SS7 ATM DDN ISDN Ethernet.etc GPRS Backbone Gs Gd Gr Gf Gc Gb Iu Um Um Gp Gi Gn Gn ATM Ga SCP GMLC Ge Lg Ga

35. G PRS N etwork S tructure Some Abbreviation GPRS: General Packet Radio Service BSS: Base Station Subsystem UTRAN: UMTS Terrestrial Radio Access Network SGSN: Service GPRS Support Node GGSN: Gateway GPRS Support Node CG: Charging Gateway BG: Bordering Gateway PDN: Packet Data Network

36. G PRS N etwork S tructure Important Entity Function __ SGSN Mobility management The mobility management functions are used to keep track of the current location of an MS within the PLMN or within another PLMN. Session management Session Management (SM) function manages the PDP context of MS. Routing and transfer SGSN performs routing and forwarding of service data between MS and GGSN. Charging SGSN can generate, store, convert and send CDRs. Lawful Interception NTP

37. G PRS N etwork S tructure Important Entity Function __ GGSN Session management Session Management (SM) function manages the PDP context of MS. Routing and transfer GGSN performs routing and forwarding of service data between MS and internet. Charging GGSN can generate, store, convert and send CDRs. Dynamic IP allocation Service management Manage APN

38. G PRS N etwork S tructure Important Entity Function __ CG Real-time collection of GPRS bills Temporary storage and buffering of GPRS bills Pre-processing of GPRS bills Sending GPRS bills to the billing center

39. G PRS N etwork S tructure Important Entity Function | DNS SGSN GGSN(A) MS BSS GPRS backbone ISP A ISP B Internet/ Intranet GGSN(B) DNS Resolve the APN to a GGSN IP in the PDP active procedure Resolve the RAI to a SGSN IP in the inter-SGSN RAU procedure Resolve the RNCID to a SGSN IP in the relocation procedure (UMTS)

40. A ttach P rocedure

41. R eject C auses by G PRS Network Cause in attach reject Actions in PS domain Actions in CS domain Illegal MS The MS shall set the GPRS update status to GU3 ROAMING NOT ALLOWED The SIM/USIM shall be considered as invalid for GPRS services until switching off or the SIM/USIM is removed If the MS is IMSI attached, the MS shall in addition set the update status to U3 ROAMING NOT ALLOWED, shall delete any TMSI, LAI and ciphering key sequence number Illegal ME GPRS services not allowed The MS shall set the GPRS update status to GU3 ROAMING NOT ALLOWED; The SIM/USIM shall be considered as invalid for GPRS services until switching off or the SIM/USIM is removed. no effect GPRS services not allowed in this PLMN shall set the GPRS update status to GU3 ROAMING NOT ALLOWED PLMN not allowed shall set the GPRS update status to GU3 ROAMING NOT ALLOWED), shall reset the GPRS attach attempt counter and shall change to state GMM-DEREGISTERED The MS shall perform a PLMN selection Location area not allowed Roaming not allowed in this location area No Suitable Cells In Location Area shall set the GPRS update status to GU3 ROAMING NOT ALLOWED The MS shall search for a suitable cell in another location area in the same PLMN

42. D etach P rocedure Detach type 　 　 　 bit4 bit3 bit2 bit1 　 　 　 　 power off detach tye 　

43. 4 G/ L TE

44. 4 G/ L TE

45. 4 G/ L TE A ttach

46. 4 G/ L TE D etach

47. H istory of I MS 2000/03 2001/03 2002/03 2005/12 2006/X 3GPP R99 CN: TDM The IMS is introduced as part of 3GPP specifications at the R5 stage, act as a subsystem of the PS domain. 3GPP R4 CN: MSC server and MGW 3GPP R6 IMS QoS, Billing, FMC, etc 3GPP R7 IMS enhance 3GPP R5 CN: IMS introduced TISPAN R1 -- NGN/FMC, etc TISPAN R2 -- NASS/RACS, etc

48. I MS M otivations Legacy Core Network Arch. Bearer Control Service Charging Database Internet Bearer Control Service Charging Database Mobile Network Bearer Control Service Charging Database Fixed Network Vertical network, overlap in hardware, service and database Separated user and service Difficult to decrease OPEX/CAPEX Multiple Application IP Bearer IMS Core (Unified session control) Unified Database/Charging Converged Multi-service Arch. Multiple Access Horizontal network, converge fixed, mobile and data service network Unified database and service Access independent Convergent Overlapping Cost

49. I MS N etwork A rchitecture Gaming Conference 3rd Party Applications SCP MGCF I-CSCF AGCF P-CSCF S-CSCF HSS Bearer Control Layer AG IAD PSTN/PLMN MGW SIP H.248 xDSL/LAN access WiFi access AP SGSN 2G/3G RAN SIP Terminals SIP SIP Bearer Core Network GGSN AC OMS OSS BGCF IM-SSF OSA Presence PTT IM Group MRFC MRFP Bearer Control and Access Session control Service capability Application A-RACF CCF SPDF PCRF H.248 NACF CLF

50. I MS N etwork E ntities Function NE Function NE Call control P － CSCF Network interworking MGCF I － CSCF IM － MGW S － CSCF BGCF User management HSS Media resource MRFC SLF MRFP PLMN/PSTN S-CSCF MGCF BGCF PLMN/PSTN S-CSCF BGCF 2 BGCF1 MGCF

51. I MS C all P rocedure (Simple Model) S-CSCF I-CSCF P-CSCF P-CSCF S-CSCF Caller part Callee part signaling media Media HSS DNS/ENUM

52. 5 G – P rimitives

53. 5 G – N ear F uture

54. 2 G  5 G R oadmap

55. T owards  5 G

56. 2 G  5 G R oadmap

57. 5 G M otivations

58. 5 G I MT-2020

59. 5 G – P rimitives

60. 5 G – N etwork Architecture

61. N F V - N etwork F unction V irtualization

62. 5 G-CRAN C loud R AN

63. 5 G – I nteroperable N etwork

64. 5 GC – I nteroperable N etwork

65. 5 GNR – N ew R adio

66. 5 GNR – N ew R adio

67. 5 G S pectrum – mm W ave

68. 5 G S pectrum – mm W ave

69. 5 G S pectrum – mm W ave

70. 5 G N etwork Slicing

71. 5 G N etwork Slicing

72. 5 G N etwork Slicing

73. 5 G N etwork Slicing

74. 5 G & A R / V R

75. 5 G & A R / V R

76. 5 G & A rtificial I ntelligence ( A I )

77. 5 G & A rtificial I ntelligence ( A I )

78. 5 G & V 2X / C onnected Cars

79. 5 G & H ealth

80. 5 G & H ealth

81. 5 G & H ealth

82. 5 G & H ealth

83. M VNOs role in 5 G M arket

84. M VNOs role in T elecom M arket

85. M VNOs role in 5 G Market

86. M VNOs role in 5 G Market

87. Thanks! Hamid Reza Bolhasani [email protected] Dec 2020