PPLIVE: A MEASUREMENT STUDY OF P2P IPTV SYSTEMSergio Chacon

ABSTRACT

IPTV stands for Internet Protocol Television P2P IPTV refers to the delivery of TV over IP

using point-to-point techniques PPLive is one of the most popular IPTV

systems for campus and residential access Hei, et al., Polytechnic University in Brooklyn,

developed a PPLive crawler to carry out in-depth measurements of mesh-pull PPLive

INTRODUCTION

Widespread adoption of broadband (residencial)

Application-level, P2P, mesh-pull P2P Mesh-Pull most successful so far

Rapid deployment @ low cost Minimal infrastructure

BitTorrent Not feasible for real time No fair resource sharing Not for large-scale live streaming

ANSWER TO QUESTIONS

What are the user characteristics? How much overhead and redundant traffic? What are characteristics of peer

partnerships? What are fundamental requirements for

successful mesh pull?

MESH-PULL P2P STREAMING SYSTEMS

Streaming peer node Includes streaming client and server

Channel stream server Converts media to small video chunks

Tracker server Provides streaming channel, peer and chunk

information for each peer node Downloads video chunks from multiple peers

requesting same media content

CHANNEL AND PEER DISCOVERY

PEE’S BUFFER MAP OF VIDEO CHUNKS

MESH-PULL P2P ARCHITECTURE

STREAMING PROCESS MESH-PULL SYSTEMS

GLOBAL VIEW OF USER BEHAVIOR

Peer tracking methodology Evolution of participating users User arrivals and departures User geographic distribution

PEER TRACKING

Peer registration Bootstrap Peer query

PEER REGISTRATION

Peer registration Bootstrap Peer query

NUMBER OF DISCOVERED PEERS

EVOLUTION OF PARTICIPATING USERS

HOW NUMBER OF USERS EVOLVE

USER ARRIVALS AND DEPARTURES

PEER ARRIVAL AND DEPARTURE EVOLUTION

USER GEOGRAPHIC DISTRIBUTION

PEER PLAYBACK DELAY AND LAGS

Start-up delay Video buffering Playback lags among peers

START-UP DELAY

Time interval between channel selection and playback

P2P also have to deal with startup buffering and delay 5-10 seconds from selection to player startup 5-10 seconds from player startup to play

VIDEO BUFFERING

PLAYBACK LAGS AMONG PEERS

CONNECTION + TRAFFIC CHARACTERISTICS

Isolating video traffic Video traffic redundancy Download and upload video traffic Video TCP connections

ISOLATING VIDEO TRAFFIC

VIDEO TRAFFIC REDUNDANCY

DOWNLOAD AND UPLOAD VIDEO

PROPERTIES OF VIDEO TCP CONNECTIONS

Duration of TCP connections Number of partners Dynamic of partners Locality of partners Traffic volume breakdowns Uni-directional or bi-directional traffic?

VIDEO TCP CONNECTIONS

NUMBER OF PARTNERS

DYNAMIC OF PARTNERS

TRAFFIC VOLUME BREAKDOWNS

LOCALITY OF PARTNERS

UNI-DIRECTIONAL OR BI-DIRECTIONAL?

UNI-DIRECTIONAL OR BI-DIRECTIONAL TRAFFIC?

Traffic flows are neither tree-like nor uni-directional (mesh)

Closer in character to BitTorrent Lesson learned: mesh-pull architectures are

more correctly viewed as variations on BitTorrent rather than variations on tree-pull architectures such as end-system multicast

CONCLUSIONS

Current Internet is capable of providing IPTV @ low cost with minimal dedicated infrastructure

Measurements provide understanding of how to architect large-scale P2P IPTV

Areas of improvement: Shorter start-up delay Higher-rate streaming Smaller peer lags Better NAT traversal