07/08/2016. Sami TABBANE. I. Introduction II. Evolved Packet Core III. Core network Dimensioning IV. Summary

Transcription

1 Core network and transmission dimensioning Sami TABBANE 1 CONTENTS I. Introduction II. Evolved Packet Core III. Core network Dimensioning IV. Summary 2 1

2 CONTENTS I. Introduction 3 Introduction LTE Commercialization 351 Operators in 104 Countries are investing in LTE 105 LTE Commercial LTE Networks Launched in 48 Countries 4 2

3 Introduction LTE: Fast Market Growth 100 LTE Commercial Launches within 3 years of the first launch WCDMA took longer than 4 year for 100 commercial launches 100M LTE Subscribers within 3.3 year expected 5 Introduction World evolution of mobile data traffic 6 3

4 Introduction 3GPP technologies are based on CDMA and OFDMA technologies WCDMA and HDPA are based on CDMA LTE is based on OFDMA 7 Introduction Advantages Provide low latency Higher network throughput Increased data transfer speed More cost effectiveness Improvements over 3G network 8 4

5 CONTENTS II. Evolved Packet Core 9 Evolved Packet Core 3GPP Core Network Evolution 3GPP Network has evolved from 4 tier architecture to 3 tier architecture 2G /3G CDMA/EV-DO GSM/GPRS EDGE UMTS HSPA Voice channels IP channel BTS NodeB BSC/RNC Circuit swirched core voice Packet swirched core data PTSN Other Mobile networks Internet VPN LTE IP channel enodeb enodeb Evolved packet core (all IP) Transport (backhaul and backbone) 10 5

6 Evolved Packet Core Evolved core network IP channel enodeb S-GW MME P-GW PCRF Service delivery platforms IP communications (VoiP, video) Messaging SMS/MMS Internet, Web 2.0 Advanced location based services Mobile Tv, IP mulimedia Mobile office 11 Evolved Packet Core Radical changes in the network End of circuit-switched voice: LTE uses a new paradigm for voice traffic VoIP. Evolved wireless broadband Mobility as a part of the core network: In LTE, all mobility management is moved into the mobile core and becomes the responsibility of the MME. 12 6

7 Evolved Packet Core Radical changes in the network End-to-end QoS becomes essential: LTE must provide superior end-to-end QoS management and enforcement in order to deliver new media-rich, low-latency and real-time services. Policy management and enforcement: Service control is provided via the Policy and Charging Rules Function (PCRF) PCRF dynamically controls and manages all data sessions and provides appropriate interfaces towards charging and billing systems. LTE requires significantly more capacity in both the data plane and control plane. 13 Evolved Packet Core 4G (LTE) architecture 2G 3G enode B RNC X2 S1-U S1-C SAE GW SGSN SGW HSS S11 MME S6a S5/S8 P-GW PCRF S7 (Gx) enode B 14 7

8 Evolved Packet Core The EPC is realized through four new elements: Serving Gateway (SG-W) Packet Data Network (PDN) Gateway (P-GW) Mobility Management Entity (MME) Policy and Charging Rules Function (PCRF) SGW, PGW and MME are introduced in 3GPP Release 8, PCRF was introduced in 3GPP Release 7 15 Evolved Packet Core Serving Gateway (S-GW) Manage user-plane mobility acts as an interface between the RAN and core networks. Maintains data paths between enodebs and the PDN Gateway (PGW). Evolved core network IP channel enodeb S-GW MME P-GW PCRF enodeb SGW is the termination point of the packet data network interface towards E-UTRAN. 16 8

9 Evolved Packet Core Packet Data Network (PDN) Gateway (P-GW) The termination point of the packet data interface towards the Packet Data Network(s). the PDN GW supports: Policy enforcement features Packet filtering (for example, deep packet inspection for application type detection) Charging support (for example, per-url charging) In LTE, data plane traffic is carried over virtual connections called service data flows (SDFs). One or more SDFs are aggregated and carried over one bearer. 17 Evolved Packet Core Mobility Management Entity (MME) It performs the signaling and control functions to manage the User Equipment (UE) access to network connections, the assignment of network resources, and the management of the mobility states to support tracking, paging, roaming and handovers The MME supports: Security procedures: End-user authentication as well as initiation and negotiation of ciphering and integrity protection algorithms. Terminal-to-network session handling Idle terminal location management 18 9

10 Evolved Packet Core Policy and charging rules function (PCRF) A concatenation of Policy Decision Function (PDF) and Charging Rules Function (CRF) A control plane element that is not strictly speaking, an EPC element, but is required to give dynamic control over bandwidth, charging, and network usage AF Policy and Charging Enforcement Function (PCEF): supports service data flow detection, policy PCRF enforcement and flow-based charging. Application Function (AF): supports applications that require dynamic policy and/or charging control. SGW PGW Online charging Offline charging shows how PCRF interfaces with other EPC elements.. 19 Evolved Packet Core EPC deployment model Deployment architecture Centralised Function Distributed Function Completely centralised Completely distributed Centralised bearer/ Distributed control Centralised control/ Distributed bearer SGSN+GGSN+MME+SGW +PGW SGW+PGW+GGSN MME MME+SGSN+GGSN+SGW +PGW MME+SGSN PGW+SGW 20 10

11 CONTENTS III. Core network Dimensioning 21 Core network Dimensioning General wireless network planning process Pre-planning Collect area parameters. Detailed information of EPC core network Superficies Dimensioning: Subscribers information Coverage and capacity constraints Requirements and Minimize exploited resources Strategy for coverage, Output capacity and quality Equipment capacity Output: Offered services Necessary capacity Number of subscribers User Traffic rate Coverage planning Signaling traffic Capacity equipment Parameters planning Optimization Performance analysis in terms of quality and interference Geographical site position Maximize the coverage KPI (Key performance indicator) QoS requirements 22 11

12 CORE NETWORK DIMENSIONING 1. Dimensioning Phases 23 Dimensioning Phases Traffic Dimensioning Equipment dimensioning Subscribers demands Dimensioning Traffic Signaling Traffic Data Traffic Number of equipment needed 24 12

13 Dimensioning Phases Dimensioning preliminary phases Initial parameters configuration Number of subscribers, N Number of smartphone Number of data card Handsets profiles configuration Traffic at Busy hour Session size Number of sessions during the busy hour Traffic percentage in DL Data traffic carried in VPNs or for Internet services Signaling Traffic Network attach and detach Bearer activation HO procedures Tracking area update 25 CORE NETWORK DIMENSIONING 2. Traffic dimensioning at BH 26 13

14 Traffic dimensioning at BH Initial parameters (Number of smartphones and data cards) N c = N A * P C N S =N A * P s Where: N c: Number of data cards N A: Total subscribers number P C : Data card percentage N S : Total smartphones number P s : Smartphones percentage 27 Traffic dimensioning at BH Smartphone profile in Busy hour With smartphones we can access to: Streaming Interactive video games Download Internet Traffic at busy hour: ρ S BH-DL/UL = (T session *N session ) Where ρ S BH-DL/UL: Traffic volume in UL/ DL at Busy hour T session : Exchanged data volume per session N session : Number of sessions at BH Service characteristics: Session size Number of possible sessions at busy hour 28 14

15 Traffic dimensioning at BH Traffic on DL: ρ S BH-DL = (ρ S BH-DL/UL ) * ρ DL Where: ρ S BH-DL/UL: Traffic volume at Busy hour ρ S BH-DL: Traffic volume on the DL ρ DL : Percentage of DL traffic 29 Traffic dimensioning at BH Traffic during BH Smartphones Total traffic ρ S DL/UL= ρ S BH-DL/UL *Ns ρ S DL/UL: Smartphone total traffic at Busy hour Data card total traffic ρ CD DL/UL= ρ CD Internet-BH-DL/UL *N CD ρ S DL/UL: Smartphone total traffic at Busy hour 30 15

16 Traffic dimensioning at BH Internet services Throughput at BH Total traffic Internet services Throughput of Internet services ρ Internet DL/UL = ρ S DL/UL + ρ CD DL/UL TH Internet BH-DL/UL = (ρ Internet DL/UL *8) / 3600 Where TH Internet BH-DL/UL: Internet services throughput at busy hour 31 Traffic dimensioning at BH VPN services Throughput during BH Number of cards supporting this services: N CD_VPN = N CD *P CD_VPN N CD_VPN: Number of cards using VPN P CD_VPN: Percentage of cards using VPN ρ VPN DL/UL = (ρ CD VPN BH-DL/UL ) * N CD_VPN TH VPN DL/UL = (ρ VPN DL/UL *8) / 3600 Where TH VPN DL/UL: Throughput VPN services at busy hour 32 16

17 Traffic dimensioning at BH Traffic in DL ρ S DL = (ρ S BH-DL) * N s ρ S DL = Smartphones total traffic in DL ρ CD DL = (ρ CD Internet BH-DL) * N CD ρ CD DL = Data cards total traffic in DL (ρ Internet BH-DL ) = ρ S DL + ρ CD DL (ρ Internet BH-DL ) T: Total traffic in DL ( Internet services) TH Internet BH-DL = ((ρ Internet DL ) *8/3600) 33 Traffic dimensioning at BH Number of active users at Busy hour N AU: Number of active user at busy hour P AU: Percentage of active user at busy hour N AU = N A *P AU Number of operations made at busy hour N Attach = N Attach/sub/BH *N AU N attach: Total number attachment N Attach/sub/BH: Number of attachment at busy hour N Detach = N Detach/sub/BH *N AU N Detach: Total number of detach N Detach/sub/BH : Number of detach at busy hour 34 17

18 Traffic dimensioning at BH N IDLE/ACTIVE = N IDLE/ACTIVE/sub/BH *N AU N IDLE/ACTIVE: Total number of transitions idle to active N IDLE/ACTIVE/sub/BH: Number of transitions idle to active at busy hour N PDN = N PDN/sub/BH *N AU N PDN: Total number of PDN connections N PDN/sub/BH: Number of PDN connections at busy hour 35 Traffic dimensioning at BH N BEARERS = N BEARERS/sub/BH *N AU N BEARERS : Total number of bearer activation and deactivation N BEARERS/sub/BH: Number of bearer activation and deactivation per user at busy hour N TAU_INTER_MME = N TAU_INTER_MME/sub/BH *N AU N TAU_INTER_MME: Total number of tracking area update inter MME N TAU_INTER_MME/sub/BH: Number of tracking area update inter MME per user at busy hour N TAU_INTER_MME_SGW = N TAU_INTER_MME_SGW/sub/BH *N AU N TAU_INTER_MME_SGW: Total number of tracking area update inter MME /SGW N TAU_INTER_MME_SGW/sub/BH: Number of tracking area update inter MME/SGW per user at busy hour 36 18

19 Traffic dimensioning at BH N X2_HO = N X2_HO/sub/BH *N AU N X2_HO : Total number of handover via X2 interface N X2_HO/sub/BH: Number of handover via X2 interface per user at busy hour N S1_HO = N S1_HO /sub/bh *N AU N S1_HO: Total number of handover via S1 interface N S1_HO/sub/BH: Number of handover via S1 interface per user at busy hour N HO_INTER_MME = N HO_INTER_MME/sub/BH *N AU N HO_INTER_MME: Total number of handover inter MME N HO_INTER_MME/sub/BH: Number of handover inter MME per user at busy hour 37 Traffic dimensioning at BH Total number of procedures at busy hour N proc = N Attach + N Detach + N IDLE/ACTIVE + N PDN + N BEARERS + N TAU_INTER_MME + N X2_HO + N S1_HO + N HO_INTER_MME N proc: Total Number of procedures 38 19

20 CORE NETWORK DIMENSIONING 3. Equipment dimensioning 39 Equipment dimensioning a) MME dimensioning 40 20

21 MME dimensioning N MME = E[ N attach / OC SAU ] N MME : Required number of MME OC SAU: Capacity MME in simultaneous users attached N MME= E[N IDLE/ACTIVE /3600)/ OC IDLE/ACTIVE] OC IDLE/ACTIVE : Capacity MME in Idle to active transactions (in seconds) N MME= E[N PROC /3600)/ OC TRANS_MME] OC TRANS_MME : Capacity MME in transactions (in seconds) 41 Equipment dimensioning b) SGW dimensioning 42 21

22 SGW dimensioning N SGW = E[ N BEARERS / OC BEARERS ] N SGW : Required number of SGW OC BEARERS : Capacity MME in bearers activation and deactivation N MME= E[N IDLE/ACTIVE /3600)/ OC IDLE/ACTIVE] For internet and VPN services: N SGW = E[ TH BH-DL-INTERNET / OC DATA-PROCESSING ] N SGW = E[ TH BH-DL-VPN / OC DATA-PROCESSING ] OC DATA-PROCESSING : Capacity data treatment 43 Equipment dimensioning c) PGW dimensioning 44 22

23 PGW dimensioning N PGW = E[ N BEARERS / OC BEARERS ] N PGW: Required number of PGW N PGW = E[ TH Bh-DL-INTERNET / OC DATA-PROCESSING ] N PGW = E[ TH Bh-DL-VPN / OC DATA-PROCESSING ] 45 Equipment dimensioning d) HSS dimensioning 46 23

24 HSS dimensioning N HSS = E[ N A / OC A ] N HSS : Required number of HSS OC A: Maximum capacity of HSS in term of subscribers 47 Equipment dimensioning d) PCRF dimensioning 48 24

25 PCRF dimensioning N PCRF = E[ N PROC /3600) / OC TANS_PCRF ] N PCRF: Required number of PCRF OC TANS_PCRF: Capacity of PCRF in term of transactions ( in seconds) 49 Equipment dimensioning e) Dimensioning of signaling procedures 50 25

26 Dimensioning of signaling procedures 0.2 T N MSG*Duration= T signal = T MSG /Throughput 0.4T T MSG : Request signaling size ( in bit) Throughput: Transmission throughput T signal : Time transmission N MSG : Number of signaling messages between network elements TH INT_C = [T MSG * N MSG * N PROC /3600] C INT_C = TH INT_C N PROC_x : Number of operations TH INT_C : Throughput per interface in the control plane C INT_C : Capacity per interface 51 CONTENTS IV. Case Study 52 26

27 Subscribers Information Area Information Population Market Evaluation 52,6 % Data Card Percentage 42 % Smartphones (% ) 27 % Total Subscribers Data cards Number Smartphones Number Subscribers Information Smart-Phone Configuration Profile UL/DL Traffic topology Number of session at BH Session size DL Percentage (%) Service Internet access VPN Active subscribers ALL 30% of data cards Web Browsing Video streaming VPN Gaming

28 CASE STUDY 1. Traffic dimensioning at BH 55 Traffic Volume UL-DL Data session profile for a Smartphone Traffic topology Number of session Session Size(Mb) Traffic Volume at busy hour UL/DL (Mb) Traffic Volume at busy hour DL (Mb) Web Browsing Video streamin g VPN Gaming Total Traffic Volume (Internet)

29 Traffic Volume UL-DL Data session profile for a Data card Traffic topology Number of session Session Size(Mb) Traffic Volume at busy hour UL/DL (Mb) Traffic Volume at busy hour DL (Mb) Internet Internet Internet VPN Internet Total Traffic Volume (Internet) Total Traffic Volume (VPN) Traffic Volume UL-DL Total traffic for office VPN and internet at BH (DL and UL) Item Total traffic at BH for Internet (Mb) Total traffic volume for all smartphones 1.99 Total traffic volume for all data cards 3.54 Total traffic (Mb) 5.54 BH throughput for intent DL&UL (Gb) Data cards using VPN 30% Total traffic VPN (MB) 0.06 BH throughput for office VPN (GB)

30 Traffic Volume UL-DL Total traffic for office VPN and internet at BH (DL) Item Total traffic at BH for Internet(Mb) Total traffic volume for all smartphones Total traffic volume for all data cards Total traffic ( Mb) BH throughput for internet DL&UL ( Gb) 8.62 Data cards using VPN 30% Total traffic VPN (MB) BH throughput for office VPN CASE STUDY 2. Dimensioning of signaling procedures 60 30

31 Dimensioning of signaling procedures Procedure Subscriber/BH Number Active user at BH 90% N attach N detach Busy Hour Active Subscriber = x 90% = N Idle to active N PDN 0, N Bearers activ/deactiv N TAUs inter MME 0, N TAUs 0, N X2- HO 0, N S1- HO 0, N HO inter MME 0, N Procedure CASE STUDY 3. Equipment dimensioning 62 31

32 Equipment dimensioning Components Metrics Unit Value Percentage Operating capacity MME SimULaneous attached users (SAU) Idle to active transition/second Subscribers % Trans/sec % 2210 Transactions/second Trans/sec % 2550 SGW PGW Number of active bearers bearers % Data processing capacity Gbps 10 85% 8.5 Number of active bearers bearers % Data processing capacity Gbps 10 85% 8.5 Combines GW/P-GW Number of active bearers bearers % Data c processing capacity Gbps 5 85% 4.25 HSS Number of users supported Subscribers % PCRF Transactions/second Trans/sec % Equipment dimensioning Required nodes Component Required number N MME-OC SAU 1 N MME-IDLE/ACTIVE 3 N MME-Proc 3 N SGW-Bearers 1 N SGW-Data Proc 2 N SGW-VPN 1 N PDNGW-Bearers 1 N PDNGW-DL Internet 2 N PDNGW-VPN 1 N SGW-PDNGW Bearers 1 N SGW-PDNGW DL Internet 3 N SGW-PDNGW DL VPN 1 N HSS 1 N PCRF

33 CONTENTS VI. Summary 65 Summary Main Challenges for the Future User QoE decrease and operator cost increase due to mobile traffic growth Operator revenue growth slows 66 33

34 Summary Many promising technologies have been identified in 3GPP Operator and consumer benefit should be carefully considered when new technologies are introduced for beyond 4G 67 Thank you 68 34