LTE (Long Term Evulation)

Evolution of Radio Access Technologies d/e m

WIRELESS ACCESS EVOLUTION  New Services  Efficiency  More Data Services required Broadband Subscribers Voice  Coverage  Mobility  Voice Quality  Portability  Capacity  Data Service  Broadband  Network Simplification  Cost of Ownership

What is 3GPP? 3GPP stands for 3 rd Generation Partnership Project It is a partnership of 6 regional SDOs (Standards Development Organizations) These SDOs take 3GPP specifications and transpose them to regional standards Japan USA

5 Two Key technologies are evolving to meet the Wireless Broadband Requirements n (smart antennas) Mesh extns. Local Area Fixed Wide Area Mobile Coverage/Mobility Metro Area Nomadic (Fixed LOS) a/d (Fixed NLOS) b/a/g Mobile Industry Fixed Wireless Industry 4G Air Interfaces Data Rates (kbps) 100,000 + GSM UMTS HSPA GPRSEDGE LTE 3GPP MOBILE BROADBAND DSL Experience Dial Up Higher Data Rate / Lower Cost per Bit e (Mobile WIMAX) Fibre Experience

+True high-speed mobile data +Full-motion HD video anywhere +Stream any content +Mobile peer2peer & Web 2.0 (Networking) +Triple play EDGE EVDO-A HSDPA LTE Fiber ADSL-2+ ADSL Mbps Mbps Fiber like speed on mobile COMPARISON WITH SPEED

+Spectral efficiency Better utilization of spectrum available +Low frequency, Advanced Receivers and Smart Antenna For improved coverage and reduced cost of ownership +Increased Capacity Much higher user and sector throughput for lower individual cost service delivery +Simpler RAN, IP Core & Centralized service delivery Fewer nodes & interfaces (Node- B/RNC/Gateway) One Network & IMS for all access technologies +Connect to legacy cores Existing network asset investment protection +3GPP/2 Market traction Economy of scale LTE VoIP cost* UMTS rel.99 voice call cost $ 10% 3GPP subscribers 85% market share Predicted LTE VoIP voice call cost* - Sound Partners Limited Research COMPARISN COST

10-5msec latency Highly Responsive Multimedia +Improved user experience +Fast VoIP call set-up +Instantaneous web pages +Streaming fast buffering +Online mobile gaming EDGE EVDO-A HSDPA LTE Fiber ADSL-2+ ADSL RESPONSE TIME

Core Network What is EPC, eUTRAN and EPS EPC = Evolved Packet Core (SAE) eUTRAN = Evolved UTRAN ( LTE RAN ) EPS = Evolved Packet System incl EPC, eUTRAN and terminals (LTE/SAE terminology only used within 3GPP standardization workgroups) Non-3GPP CS networks ”IP networks” 3G 2G Circuit Core IMS domain EPC eUTRAN User mgmt

LTE Offer’s Performance and capacity DL 100 Mbps AND UL 50 Mbps Simplicity Flexible Bandwidths (5Mhz-20Mhz), FDD and TDD plug-and-play Devices self-configuration Devices self-optimization Devices

LTE ACCESS LTE radio access  Downlink: OFDM  Uplink: SC-FDMA Advanced antenna solutions  Diversity  Beam-forming  Multi-layer transmission (MIMO) Spectrum flexibility  Flexible bandwidth  New and existing bands  Duplex flexibility: FDD and TDD 20 MHz1.4 MHz TX SC-FDMA OFDMA

FREQUENCY BEND

LTE (Long Term Evolution) Radio Side (LTE – Long Term Evolution)  Improvements in spectral efficiency, user throughput, latency  Simplification of the radio network  Efficient support of packet based services Network Side (SAE – System Architecture Evolution)  Improvement in latency, capacity, throughput  Simplification of the core network  Optimization for IP traffic and services  Simplified support and handover to non-3GPP access technologies

LTE ARCHITECTURE EvolvedPacketCore MME/UPE = Mobility Management Entity/User Plane Entity eNB = eNodeB

EVOLVED PACKET CORE NETWORK MME P-GW/S-GW MME P-GW/S-GW LTE NODE B S11 S1-Cp X2 Gi Interfaces Air Interface EPCEPC EUTRANEUTRAN

3G NETWORK GGSN IP networks SGSN Iu Gb 2G3G BSC BTS RNC Node B HLR/HSS Gr Gi LTE/SAE Architecture Iur Only PS Domain shown Gn

HSPA (HIGH SPEED PACKET DATA ACCESS) GGSN IP networks SGSN Iu CP Gb 2G3G BSC BTS RNC Node B HLR/HSS PCRF Iu UP Gr Gi LTE/SAE Architecture Iur Gx Only PS Domain shown Gn Optimizing the 3G/HSPA payload plane for Broadband traffic Release 7 ”Direct Tunnel”

LTE/EPC Network Architecture GGSN => Packet Gateway SGSN => Mobility server BSC RNC SGSN/ MME GGSN/ P/S-GW GSM, WCDMA IP networks LTE EPC MME = Mobility Management Entity P/S-GW = PDN/Serving gateway

LTE/SAE PDN GW Serving GW MME S1-MME S1-U LTE IP networks eNodeB SGSN Iu CP Gb 2G3G S3 BSC BTS RNC Node B HLR/HSS PCRF Iu UP S11 Gr S10 S6a SGi LTE/SAE Architecture X2 Iur S7 Non-3GPP access S2a/b The PDN and Serving GW may be separate nodes in some scenarios (S5 in-between) A flat architecture for optimized performance and cost efficiency Only PS Domain shown S4

KEY NODES OF LTE MME Functionality Responsibilities is to keep track of terminals in idle Mobility handling Authentication Roaming SGSN can be software upgraded to a MME and after that function as a combined SGSN and MME SGi MME S1-MME S1-U S11 X2 S10 eNodeB S3 S4 SGSN SAE GW

SAE GW Functionality PDN SAE GW (ANCHOR)  Anchor for mobility non 3GPP Network (Wimax and other Network) Serving SAE GW:  Routing  Anchor inter 3-GPP mobility (GSM/3G/4G Netowork)  Security  Lawful Intercept P/S-GW node, which also can be a software upgrade of a current GGSN node. SGi MME S1-MME S1-U S11 X2 S10 eNodeB S3 S4 SGSN SAE GW

LTE/SAE Architecture Main SAE interfaces (non-roaming case) S1-MME S1-U IP networks S3 S11 S10 SGi S4 S5/S8 (SGi) X2 SAE CN Architecture OSS-RC S1-MME: control plane protocol between eNodeB and MME S1-U: user plane tunneling interface between eNodeB and Serving GW S5: user plane tunneling interface between Serving GW and PDN GW S8: user plane tunneling interface between Serving GW and PDN GW for roaming S10: control plane interface between MME and MME S11: control plane interface between MME and Serving GW. S4: *) user plane tunneling interface between SGSN and PDN GW S3: *) control plane interface between MME and SGSN. *) Note: Interfaces non-3GPP accesses not covered. SAE GW MME eNodeB SGSN SAE GW (in some use cases only)

CALLING PATH FROM 2G TO 3G NETWORKS

25 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

26 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

27 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

28 BSC Base Station Controller The call request reaches the BSC from the BTS and is forwarded to SGSN. The call request reaches the BSC from the BTS and is forwarded to SGSN. After call is established, the BSC will perform decoding of the call (in typical config.) After call is established, the BSC will perform decoding of the call (in typical config.)

29 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

30 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

31 SGSN Serving GPRS Support Node SGSN used for packet routing. It also working as MSC/VLR The SGSN used in 2G/3G networks is converted to a Mobile Management Entity, MME. SGSN says I don’t know the location of subscriber B so that’s why I am sending the request to HLR for finding the location.

32 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

33 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

34 HSS/HLR Home Subscription Server / Home Location Register The HSS/HLR stores all the user data. It registers the location of the user in the visited network. HLR/HSS says ’I am the home of the B subscriber and I know where he/she is right now HLR/HSS says ’I am the home of the B subscriber and I know where he/she is right now. It tells to the SGSN back. It tells to the SGSN back.

35 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

36 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

37 SGSN Serving gateway Support Node It says OK I collected the information about subscriber and store it temporarily. I am sending to the information to P-GW & S-GW by MME

38 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

39 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

40 MME Mobility Management Entity MME Functionality Responsibilities is to keep track of terminals in idle Mobility handling Authentication Roaming

41 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

42 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

43 P-GW/ S-GW Packet Data Network Gateway/ Serving P-GW It uses for switching and mobility management between subscriber. Serving SAE GW: Routing Anchor inter 3-GPP mobility (GSM/3G/4G Network) Security Lawful Intercept It is the IP point of attachment for the user. The P-GW allocates the IP address to the user A, that enables it to communicate with other IP hosts in the external networks, or the internet.

44 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

45 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

46 PCRF Policy & Charging Resource Function The PCRF is the network element that is responsible for Policy and Charging Control. it performs decisions on how to handle the service in terms of QoS (Quality of Service).

47 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

48 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP

49 P-GW/ S-GW It takes information from PRCF PRCF provides information to the PCEF (Policy and Charging Enforcement Function) located in the P-GW, after verify the charging functionality. If necessary to BBERF (Binding and Event Reporting Function) located in the SGW, to set up the appropriate bearers and policy.

50 MME PCRF SGSN HLR/HSS S-GW P-GW IP Network, Internet /Services BTS BSC A 2G Subscriber A 3G Subscriber RNC Node B A LTE Subscriber eNodeB B Non 3GPP Node B B 3GPP BSC

3G- R’99 HSPA HSPA Evolution LTE / kbps3.6 Mbps21/28/42 Mbps~150 MbpsPeak rate /14 Mbps Mobile broadband speed evolution LTE Evolution Gbps Target

LTE All-IP RAN OVERVIEW Switching site 2G3G RNCBSC LTE SGW Mobile backhaul Metro, HRAN Fibre Microwave Copper Access, LRAN RBS site No Revolution - Just Evolution of Existing Infrastructure IP/MPLS (metro ethernet) LRAN L2 or L3 possible Router somewhere in the LRAN/HRAN network HRAN L3, IP/MPLS Redundancy Security GW, if IPsec used eNodeB Peak rates: Mpbs Fibre/microwave to site E-LAN or E-Line SGw Located at Switching Site All-IP, 3..4 CoS classes

LTE/SAE Architecture Product dimension PDN GW Serving GW MME S1-MME S1-U LTE IP networks eNodeB SGSN Iu CP Gb 2G3G S3 BSC BTS RNC Node B HLR/HSS PCRF Iu UP S11 Gr S10 S6a SGi LTE/SAE Architecture X2 Iur S7 Non-3GPP access S2a/b S4 PDN GW Serving GW ”Gateway” MMESGSN ”Mobility Server” PCRF HLR/HSS ”HLR/HSS” EPC eNode B RBS OSS PA/DU Core & IMS PA/DU Radio

THANKS

LTE SECRETS 2 main issues have been investigated:  The physical layer  The access network internal architecture Physical layer  Downlink based on OFDMA OFDMA offers improved spectral efficiency, capacity etc  Uplink based on SC-FDMA SC-FDMA is technically similar to OFDMA but is better suited for uplink from hand-held devices (battery power considerations)  For both FDD and TDD modes (User Equipment to support both) With Similar framing + an option for TD SCDMA framing also Access Network consideration  For the access network it was agreed to get rid of the RNC which minimized the number of nodes

LTE RELEASE  Release 99 (2000): UMTS/WCDMA  Release 5 (2002) : HSDPA  Release 6 (2005) : HSUPA, MBMS (Multimedia Broadcast/Multicast Services)  Release 7 (2007) : DL MIMO, IMS (IP Multimedia Subsystem), optimized real-time services (VoIP, gaming, push-to-talk).  Release 8(2009) :LTE (Long Term Evolution)

IP Networks. General concepts OSI model (1978)  Based on 7 layers

OSI and SS7 Model OSISS7

Layers Description Packet Data Convergence Protocol (PDCP) Performs IP header compression Reduces the number of bits to transmit over the radio Interfaced Based on Robust Header Compression (ROHC) Radio Link Control (RLC) Responsible for Segmentation/concatenation Retransmission handling In-sequence delivery to higher layers Located in the eNodeB since no higher layers exists in LTE In WCDMA this was handled higher in hierarchy Medium Access Control (MAC) Responsible for Uplink/downlink scheduling Hybrid-ARQ retransmissions Choice of modulation Resource assignment Physical Layer (PHY) Responsible for Coding/decoding Modulation/demodulation Resource mapping