Transcript P-GW
LTE (Long Term Evulation) Evolution of Radio Access Technologies 802.16m 802.16d/e 2 WIRELESS ACCESS EVOLUTION Subscribers Broadband Network Simplification New Services Efficiency Voice Quality Portability Voice Coverage Capacity Mobility Data Service Broadband More Data Services required Cost of Ownership What is 3GPP? 3GPP stands for 3rd Generation Partnership Project It is a partnership of 6 regional SDOs (Standards Development Organizations) Japan USA These SDOs take 3GPP specifications and transpose them to regional standards Two Key technologies are evolving to meet the Wireless Broadband Requirements MOBILE BROADBAND Metro Area Nomadic GSM GPRS EDGE UMTS HSPA LTE 3GPP 802.16e (Mobile WIMAX) Mobile Industry 802.16a/d (Fixed NLOS) Fixed Wireless Industry Local Area Fixed Coverage/Mobility Wide Area Mobile 4G Air Interfaces Dial Up DSL Experience Fibre Experience Data Rates (kbps) 802.16 (Fixed LOS) 802.11n (smart antennas) 802.11 Mesh extns. 802.11b/a/g 100,000 + Higher Data Rate / Lower Cost per Bit 5 COMPARISON WITH SPEED 40-100Mbps Fiber like speed on mobile + True high-speed mobile data + Full-motion HD video anywhere + Stream any content + Mobile peer2peer & Web 2.0 EDGE ADSL (Networking) EVDO-A HSDPA ADSL-2+ + Triple play LTE Fiber Mbps COMPARISN COST + 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 $ UMTS rel.99 voice call cost 10% LTE VoIP cost* Predicted LTE VoIP voice call cost* - Sound Partners Limited Research + Simpler RAN, IP Core & Centralized service delivery Fewer nodes & interfaces (NodeB/RNC/Gateway) One Network & IMS for all access technologies + Connect to legacy cores Existing network asset investment protection + 3GPP/2 Market traction 3GPP subscribers 85% market share Economy of scale RESPONSE TIME 10-5msec latency Highly Responsive Multimedia + Improved user experience + Fast VoIP call set-up + Instantaneous web pages + Streaming fast buffering EDGE ADSL EVDO-A HSDPA ADSL-2+ LTE Fiber + Online mobile gaming What is EPC, eUTRAN and EPS CS networks Core Network 2G Circuit Core 3G User mgmt IMS domain eUTRAN EPC Non-3GPP 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) ”IP networks” 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 OFDMA SC-FDMA Advanced antenna solutions Diversity Beam-forming Multi-layer transmission (MIMO) TX TX Spectrum flexibility Flexible bandwidth New and existing bands Duplex flexibility: FDD and TDD 1.4 MHz 20 MHz 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 MME/UPE MME/UPE EPC Evolved Packet Core S1 E-UTRAN X2 eNB eNB X2 X2 eNB MME/UPE = Mobility Management Entity/User Plane Entity eNB = eNodeB EVOLVED PACKET CORE NETWORK P-GW/S-GW P-GW/S-GW P-GW/S-GW P-GW/S-GW E Interfaces P MME MME MME S11 C S1-Cp X2 Gi E U T R A N LTE NODE B LTE NODE B LTE NODE B LTE NODE B LTE NODE B Air Interface LTE/SAE Architecture 3G NETWORK IP networks Only PS Domain shown Gi HLR/HSS Gr Gn Gn GGSN SGSN Gb Iu BSC RNC BTS Node B 2G 3G Iur LTE/SAE Architecture HSPA (HIGH SPEED PACKET DATA ACCESS) IP networks Only PS Domain shown Gi HLR/HSS PCRF Gr Gx Gn GGSN SGSN Gb Iu CP Iu UP BSC RNC BTS Node B 2G Optimizing the 3G/HSPA payload plane for Broadband traffic Iur 3G Release 7 ”Direct Tunnel” LTE/EPC Network Architecture GGSN => Packet Gateway SGSN => Mobility server IP networks GGSN/ P/S-GW SGSN/ MME EPC BSC RNC GSM, WCDMA MME = Mobility Management Entity P/S-GW = PDN/Serving gateway LTE LTE/SAE Architecture LTE/SAE Only PS Domain shown The PDN and Serving GW may be separate nodes in some scenarios (S5 in-between) HLR/HSS IP networks SGi PCRF Gr S6a S7 S4 SGSN S3 MME S11 PDN GW Serving GW S2a/b S10 Gb Iu CP Iu UP S1-MME BSC RNC S1-U Iur eNodeB BTS 2G X2 Node B 3G LTE Non-3GPP access A flat architecture for optimized performance and cost efficiency KEY NODES OF LTE SGi SGSN MME Functionality S3 MME S4 S11 SAE GW S10 S1-MME S1-U eNodeB 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 X2 SAE GW Functionality SGi SGSN S3 PDN SAE GW (ANCHOR) MME S4 S11 SAE GW S10 S1-MME eNodeB Serving SAE GW: Anchor for mobility non 3GPP Network (Wimax and other Network) S1-U 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. X2 SAE CN Architecture LTE/SAE Architecture Main SAE interfaces (non-roaming case) S1-MME: *) IP networks control plane protocol between OSS-RC eNodeB and MME (SGi) S1-U: user plane tunneling interface SGi between eNodeB and Serving GW SAE GW S5: S5/S8 (in some use cases only) user plane tunneling interface S4 between Serving GW and PDN GW SAE GW S11 S3 S8: SGSN MME user plane tunneling interface between Serving GW and PDN GW S10 for roaming S10: S1-U S1-MME control plane interface between MME and MME S11: control plane interface between MME X2 eNodeB and Serving GW. S4: *) user plane tunneling interface between SGSN and PDN GW S3: *) control plane interface between MME Note: Interfaces non-3GPP accesses not covered. and SGSN. CALLING PATH FROM 2G TO 3G NETWORKS BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 25 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 26 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 27 BSC Base Station Controller 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.) 28 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 29 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 30 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. 31 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 32 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 33 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. •It tells to the SGSN back. 34 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 35 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 36 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 37 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 38 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 39 MME Mobility Management Entity MME Functionality Responsibilities is to keep track of terminals in idle Mobility handling Authentication Roaming 40 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 41 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 42 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. 43 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 44 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 45 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). 46 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 47 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF B Non 3GPP 48 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. 49 BSC BTS A 2G Subscriber A 3G Subscriber Node B Node B RNC eNodeB A LTE Subscriber SGSN MME S-GW HLR/HSS P-GW IP Network, Internet /Services B 3GPP PCRF BSC B Non 3GPP 50 Mobile broadband speed evolution LTE Evolution LTE HSPA Evolution HSPA 3G- R’99 Peak rate 384 kbps 2002 3.6 Mbps 2005 7/14 Mbps 2007 21/28/42 Mbps ~150 Mbps Target 1 Gbps 2008/2009 2009 2013 LTE All-IP RAN OVERVIEW RBS site Mobile backhaul Switching site All-IP, 3..4 CoS classes 2G Microwave BSC IP/MPLS Copper (metro ethernet) 3G RNC Fibre SGW LTE Metro, HRAN Access, LRAN eNodeB LRAN HRAN SGw • Peak rates: 150..300 Mpbs • L2 or L3 possible • L3, IP/MPLS • Fibre/microwave to site • Router somewhere in the LRAN/HRAN network • Redundancy • Located at Switching Site • E-LAN or E-Line • Security GW, if IPsec used No Revolution - Just Evolution of Existing Infrastructure LTE/SAE Architecture LTE/SAE Architecture Product dimension PA/DU Core & IMS IP networks SGi HLR/HSS HLR/HSS ”HLR/HSS” Gr PCRF PCRF S6a S7 EPC S4 SGSN SGSN S3 MME MME S11 ”Mobility Server”S10 Gb Iu CP PDN GW PDN GW Serving GW Serving GW ”Gateway” Iu UP S1-MME BSC RNC Iur S1-U RBS eNodeBB eNode BTS 2G S2a/b PA/DU Radio X2 Node B 3G LTE OSS Non-3GPP access THANKS LTE SECRETS 2 main issues have been investigated: The physical layer The access network internal architecture Physical layer Downlink based on OFDMA 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) OFDMA offers improved spectral efficiency, capacity etc 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 OSI SS7 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