Wprowadzenie do techniki LTE. Prowadzący: Szymon Raksimowicz

Transcription

1 Wprowadzenie do techniki LTE Prowadzący: Szymon Raksimowicz Warszawa, maj 2014

2 Wprowadzenie do techniki LTE Szymon Raksimowicz

3 Agenda 1. Wprowadzenie 2. Architektura EPS 3. Interfejs radiowy 4. Stos protokołów 5. Identyfikatory 6. Stany w EPS 7. EPS bearer 8. Bezpieczeńatwo w EPS

4 Wprowadzenie 3GPP (ang. Third Generation Partnership Project) (Japonia) (Chiny) (Korea) (USA) (Europa) (Japonia)

5 Wprowadzenie 3GPP

6 Wprowadzenie

7 LTE=4G?

8 Wprowadzenie Założenia (3GPP TR ) : DL 100 Mbit/s 300 Mbit/s UL 50 Mbit/s 75 Mbit/s pasmo do 20 MHz MIMO (ang. Multiple Input, Multiple Output) zmniejszenie opóźnień kompatybilność z systemami 3GPP i non-3gpp do 350 km/h 500 km/h

9 Wprowadzenie SAE (System Architecture Evolution) LTE (Long Term Evolution) EPS (Evolved Packet System) EPC (Evolved Packet Core) E-UTRAN (Evolved Universal Terrestrial Radio Access Network )

10 Architektura EPS

11 Architektura EPS UTRAN UE LTE-Uu GERAN S1-MME E-UTRAN S1-U SGSN S3 MME S11 S10 HSS S6a S4 Serving Gateway S12 S5 Gx PDN Gateway PCRF SGi Rx Operator's IP Services (e.g. IMS, PSS etc.) HSS - Home Subscriber Server PCRF - Policy and Charging Rules Function 3GPP TS

12 enodeb Functions for Radio Resource Management: Radio Bearer Control, Radio Admission Control, Connection Mobility Control, Dynamic allocation of resources to UEs in both uplink and downlink (scheduling); IP header compression and encryption of user data stream; Selection of an MME at UE attachment when 3GPP TS

13 MME (Mobility Management Entity) NAS signalling and security; AS Security control; Inter CN node signalling for mobility between 3GPP access networks; Idle mode UE Reachability (including control and execution of paging retransmission); Tracking Area list management (for UE in idle and active mode); PDN GW and Serving GW selection; MME selection for handovers with MME change; SGSN selection for handovers to 2G or 3G 3GPP access networks; Authentication; Bearer management functions including dedicated bearer establishment; 3GPP TS

14 S-GW (Serving Gateway) The local Mobility Anchor point for inter-enb handover; Mobility anchoring for inter-3gpp mobility; E-UTRAN idle mode downlink packet buffering and initiation of network triggered service request procedure; Lawful Interception; Packet routeing and forwarding; Transport level packet marking in the uplink and the downlink; Accounting on user and QCI granularity for inter-operator charging; UL and DL charging per UE, PDN, and QCI. 3GPP TS

15 P-GW (PDN Gateway ) Per-user based packet filtering (by e.g. deep packet inspection); Lawful Interception; UE IP address allocation; Transport level packet marking in the uplink and the downlink; UL and DL service level charging, gating and rate enforcement; DL rate enforcement based on APN-AMBR; 3GPP TS

16 E-UTRAN i EPC

17 Interfejs radiowy UMTS/HSPA WCDMA (ang. Wideband Code Division Multiple Access) LTE OFDMA (DL) (ang. Orthogonal Frequency Division Multiple Access) SC-FDMA (UL) (ang. Single Carrier Frequency Division Multiple Access)

18 Zasoby radiowe One downlink slot Tslot DL Nsymb OFDM symbols k N N DL RB N DL symb RB sc N 1 Resource block RB sc resource elements 1 Slot = 0,5 ms, 7 OFDM symboli 12 podnośnych, 180 khz RB = 12*7 = 84 RE subcarriers subcarriers Resource element ( k, l) Resource Element (RE) QPSK 2 bity 16QAM 4 bity 64QAM 6 bitów DL l 0 l N symb 1 k 0 3GPP TS

19 Zasoby radiowe

20 Zasoby radiowe Pasmo [MHz] Liczba RB Liczba podnośnyc h Zajęte pasmo [MHz] Pasmo ochronne x0.16 MHz x0.15 MHz x0.25 MHz x0. 5 MHz x0.75 MHz x1 MHz

21 Zasoby radiowe One slot, T slot = 15360T s = 0.5 ms One radio frame, T f = T s = 10 ms #0 #1 #2 #3 #18 #19 One subframe 3GPP TS

22 Zasoby radiowe

23 Kanały w EPS PCCH Paging Control Channel BCCH - Broadcast control channel CCCH - Common control channel DCCH - Dedicated control channel DTCH - Dedicated traffic channel MCCH - Multicast control channel MTCH - Multicast traffic channel

24 Stos protokołów Control Plane NAS RRC PDCP RRC PDCP Relay S1-AP SCTP NAS S1-AP SCTP RLC RLC IP IP MAC MAC L2 L2 L1 L1 L1 L1 UE LTE-Uu enodeb S1-MME MME NAS Non access Stratum RRC - Radio Resource Control PDCP - Packet Data Convergence Protocol RLC- Radio Link Control MAC - Medium Access Control S1-AP S1 Application Protocol SCTP - Stream Control Transmission Protocol

25 Stos protokołów Control Plane GTP-C GTP-C GTP-C GTP-C UDP UDP UDP UDP IP IP IP IP L2 L2 L2 L2 L1 L1 L1 L1 MME S11 S-GW S - GW S5 or S8 P-GW Diameter Diameter SCTP SCTP IP IP L2 L1 L2 L1 GTP - GPRS tunnelling protocol MME S6a HSS

26 Stos protokołów User Plane Application IP IP PDCP PDCP Relay GTP-U GTP-U Relay GTP-U GTP-U RLC RLC UDP/IP UDP/IP UDP/IP UDP/IP MAC MAC L2 L2 L2 L2 L1 L1 L1 L1 L1 L1 UE LTE-Uu enodeb S1-U Serving GW S5/S8 a PDN GW SGi

27 Identyfikatory

28 Stany w EPS Detach, Attach Reject, TAU reject, E-UTRAN interface switched off due to Non-3GPP handover, All bearers deactivated EMM-DEREGISTERED EMM-REGISTERED Attach accept EMM state model in UE Detach, Attach Reject, TAU reject, All bearers deactivated EMM-DEREGISTERED EMM-REGISTERED Attach accept TAU accept for a UE selecting E-UTRAN from GERAN/UTRAN EMM state model in MME

29 Stany w EPS RRC connection released ECM-IDLE ECM-CONNECTED RRC connection established ECM state model in UE ECM-IDLE S1 connection released ECM-CONNECTED S1 connection established ECM state model in MME

30 EPS bearer

31 EPS bearer Application / Service Layer UL Traffic Flow Aggregates DL Traffic Flow Aggregates UL-TFT UL-TFT RB-ID RB-ID S1-TEID DL-TFT DL-TFT S5/S8-TEID S1-TEID S5/S8-TEID UE enodeb enb Serving GW PDN GW Radio Bearer S1 Bearer S5/S8 Bearer

32 EPS bearer SAE Bearer QoS QCI ARP Bearer Delay Loss GBR GBR MBR Non-GBR AMBR ARP Allocation and Retention Priority GBR Guaranteed Bit Rate MBR Maximum Bit Rate AMBR Aggregate Maximum Bit Rate

33 Charakterystka QCI QCI Resource Type Priority Packet Delay Budget Packet Error Loss Rate Example Services ms 10-2 Conversational Voice ms 10-3 Conversational Video (Live Streaming) GBR ms 10-3 Real Time Gaming ms 10-6 Non-Conversational Video (Buffered Streaming) ms 10-6 IMS Signalling 6 Video (Buffered Streaming) ms 10-6 TCP-based (e.g., www, , chat, ftp, p2p file sharing, progressive video, etc.) 7 Non-GBR Voice, ms 10-3 Video (Live Streaming) Interactive Gaming 8 8 Video (Buffered Streaming) 300 ms 10-6 TCP-based (e.g., www, , chat, ftp, p2p file 9 9 sharing, progressive video, etc.) 3GPP TS

34 Bezpieczeństwo w EPS

35 Kategorie UE UE Category Maximum number of DL-SCH transport block bits received within a TTI (Note) Maximum number of bits of a DL-SCH transport block received within a TTI Total number of soft channel bits Category Category Category Category Category Category (4 layers) or (2 layers) Category (4 layers) or (2 layers) Category Maximum number of supported layers for spatial multiplexing in DL 3GPP TS

36 Kategorie UE UE Category Maximum number of UL-SCH transport block bits transmitted within a TTI Maximum number of bits of an UL- SCH transport block transmitted within a TTI Category No Category No Category No Category No Category Yes Category No Category No Category Yes Support for 64QAM in UL 3GPP TS

37 LTE w praktyce Szerokość kanału radiowego Downlink Uplink 20 MHz 100 Mbit/s 48 Mbit/s 15 MHz 99 Mbit/s 35 Mbit/s 10 MHz 70 Mbit/s 23 Mbit/s 5 MHz 33 Mbit/s 10 Mbit/s

38 Częstotliwości pod LTE

39 Procedury (3GPP TS ) Attach TAU UE triggered Service Request Network Triggered Service Request

40 Pytania?