5G World Summit London, 30 th June 2016

Transcription

1 5G World Summit London, 30 th June 2016 QoE as a key driver for network evolution path in All-IP scenario Daniele Roffinella & Lorenzo Santilli Telecom Italia

2 The rise of the All-IP world All Applications & Services will be «IP-based» Exabytes / Month the IP Traffic will constantly grow Cisco VNI Global IP Traffic Forecast and most of the IP traffic will be video Cisco The Zettabyte Era The sum of all forms of video (TV, video on demand, Internet, P2P) will be in the range of 80% to 90% of global consumer traffic by

3 Telcos are investing a lot to increase speed on Fixed Copper technologies Fiber Fiber technologies technologies Performance Performance 40/10 Gbps 1.6/0,4 Gbps average per user (*) G.FAST Up to 1Gbps for Loop <100m NG PON2 VDSL Vectoring Up to 50Mbps for Loop < 700 m E-VDSL Up to 100Mbps for Loop < 300 m Up to 200Mbps for Loop < 300 m t 2,5/1,25 Gbit/s shared 100/50 Mbps average per user (*) GPON /2,5 Gbit/s 400/100 Mbps average per user (*) 2012 XG-PON t On the copper line: more bandwidth but for shorter loops! Fiber is needed deep in the access network (*) Average per user in the hypotesis of splitting factor 1:64 and active HH contemporary factor of 50% 3

4 An example of TIM effort in Fiber deployment TIM is going to cover 84% of households by 2018, deploying about 18 millions Km of fiber all over the Country with complementary FTTC and FTTH approach Source : 2015 EU Industrial R&D Investment Scoreboard (updated 2016, April) 4

5 and Mobile Networks as well 3 Gbps Feature available 1 Gbps Technology evolution feature LTE/ LTE-A DL UL 100 Mbps 150 Mbps 50 Mbps 300 Mbps 75 Mbps 168 Mbps 500 Mbps 46+ Mbps 336+ Mbps 84 Mbps 23 Mbps HSPA+ DL 21 Mbps UL 42 Mbps 5 Mbps Mbps Commercial HSPA+ Commercial LTE HSPA Evolution DC and LTE evolution HSPA+ Advanced LTE Advanced

6 but perhaps it is not crystal clear to all that APPLICATION THROUGHPUT BIT-RATE Services & End-User Requirements Telco Costs THROUGHPUT << BIT-RATE!!! a subjective example 40-50% of the available bit rate is used * Sample measures at my home 6

7 the «bit-rate waste» is everywere and it gets worse for higher Bit Rates! ( # ) Akamai connection speed ( Throughput ) - (4Q13) (4Q14) (*) Ookla SpeedTest data ( Bit Rate) - (4Q13) (4Q14) For growing bit-rate: the ratio Throughput / BitRate decreases the bit rate capacity waste is more severe EU calculated as the average of Italy, UK, Spain, Germany, France, Finland, Denmark, Nederland, Sweden, Romania 7

8 Focus on: IP Transport Performance and QoE Since most of Internet traffic is TCP based, in order to «properly design and manage» IP Networks (no bottlenecks or systematic congestion) 2 parameters that limit TCP performances have to be carefully optimized: Network Latency (RTT) and Packet Loss (PLR) TCP APPLICATION Internet Reference Model C: a constant typical range: 0,9 1,1 TCP throughput < Rif: M.Mathis et Al., Macroscopic Behavior of TCP Congestion Avoidance Algorithm, July 1997 MSS: Maximum Segment Size e. g. 1,5Kbytes C MSS RTT RTT: Round Trip Time between the TCP connection end-points PLR: Packet Loss on the path PLR between the TCP connection end-points 8

9 Data rate [ Mbps ] TCP max. Throughput - RTT - Packet Loss MAX TCP Throughput Access Bit Rate 30 High Application Throughput requires low delay and low packet loss When RTT is high, the Throughput is low, even if the bit rate is high! Rif: M.Mathis et Al., Macroscopic Behavior of TCP Congestion Avoidance Algorithm, July 1997

10 Mastering QoE A «layered» vision might help Platforms Regulation Over The Net Applications Telco Applications Third Parties Applications Out of the NN Regulation Scope Value Added delivery Net Value and Quality Functions Net Neutrality Regulation Constraints IP basic connectivity Network basic Functions 10

11 Use Case: IP Basic Connectivity End-to-end functions provided at different logical layers and tailored for specific «asset provisioning» may be seen as a slice. E.g: some applications may ask for a simple IP basic connectivity Telco Applications Third Parties Applications Operator services, Enterprise, Vertical Slice «IP Basic Connectivity» Network Value Functions CP/UP CP UP Control functions, Real Time Mgmt (e.g. Mobility/Session Mgmt, BNG functions, vcpe ) Access Node Networking Node QoE/Net Value enabling function Control function Network Slice 11

12 Use Case: Quality Enhanced Delivery..other applications (e.g. video services) typically ask for specific requirements better addressed with dedicated QoE platforms. Telco Applications Third Parties Applications Operator services, Enterprise/Vertical Slice «Quality Enhanced Delivery» Network Value Functions CP/UP UP TCP accel CP Caching Quality Enhanced Functions (e.g. Caching, TCP accelerator ) in addition to IP Basic Connectivity Access Node Networking Node QoE/Net Value enabling function Control function Network Slice 12

13 So how to improve QoE? Reduce the RTT and x PLR! in order to improve QoE it is not sufficient to work at the «IP basic connectivity» level only it takes to work on Application Transport (layer 4) i.e. use QoE Platforms UBB access Network All-IP Domestic Network QoE Platforms. Mobile Access Fixed Access Aggregation Metro Regional Core International Network 13

14 «Sky» Functions (caching, acceleration) improve QoE TCP Acceleration Caching TCP Acceleration Caching Both are QoE Enhancement Functions, operating over the IP Network Layer ( no regulation restrictions expected) Throughput Improvement Suitable for all TCP-based traffic better for «bulk data flows» (e.g. high def. Video) Suitable for «fixed» and «mobile» Throughput Improvement & Network Capacity saving Suitable for all TCP-based unencrypted traffic - better for «popular contents» Throughput improvement depends on «where» deployed in the network Best «in the middle» of E2E path Best «near to EndUsers» ( but depends also on Cache Efficiency ) 14

15 Aggregation Metro CORE Throughput Improvement by Cache & Accelerator Speed up conservative evaluation (related only to RTT reduction) Remote Server One Cache + One Accelerator Case Study Range ITZ GTW RTT Tot Core Node Case Study Range Accelerator Cache ACCESS EDGE Metro Node Access Node RTT Accelerator RTT Cache End Users Case Study Range EC Cache Efficiency (Hit Ratio); EA Accelerator Efficiency 15

16 Take away For «properly designed and managed» IP Networks (no bottlenecks or systematic congestion), performance/qoe is mainly limited by: Network Latency Packet Loss Bandwidth increase and QoS Functionalities (e.g. CoS, ToS ) are not sufficient to improve User Experience QoE platforms (e.g. CDN, Cache, Protocol Accelerator ) are needed to reach the differentiated QoE levels required by Applications 16

17 Grazie! 17