Towards Network-Failure-Tolerant Web Content Delivery: A Path-Aware Peer-Assisted Approach

Popularly used to distribute a variety of multimedia content items in today's Internet, HTTP-based web content delivery still suffers from various content delivery failures, including server failures [1], network failures [2] and routing failures [3]. Hindered by the expensive deployment cost, the conventional CDN can not deploy as many edge servers as possible to successfully deliver content items to all users under these delivery failures. In this paper, we propose a joint CDN and peer-assisted web content delivery framework to address the delivery failure problem. Different from conventional peer- assisted approaches for web content delivery, which mainly focus on alleviating the CDN servers' bandwidth load, we study how to use a browser-based peer-assisted scheme, namely WebRTC, to resolve content delivery failures. To this end, we carry out large-scale measurement studies on how users access and view webpages. Our measurement results demonstrate the challenges (e.g., peers stay on a webpage extremely short) that can not be directly solved by conventional P2P strategies, and some important webpage viewing patterns (e.g., predictability of users' webpage viewing time). Due to these unique characteristics, WebRTC peers open up new possibilities for helping the web content delivery, coming with the problem of how to utilize the dynamic resources efficiently. We formulate the peer selection that is the critical strategy in our framework, as an optimization problem, and design a heuristic algorithm based on the mea- surement insights to solve it. Our simulation experiments driven by the traces from Tencent QZone, one of the most popular social service platforms in China, demonstrate the effectiveness of our design: compared with non-peer-assisted strategy and random peer selection strategy, our design significantly improves the successful relay ratio of web content items under network failures, e.g., our design improves the content download ratio up to 60% even when users located in a particular region (e.g., city) where none can connect to the regional CDN server.

[1]  Vivek S. Pai,et al.  Understanding and improving modern web traffic caching , 2011 .

[2]  Reza Rejaie,et al.  Understanding mesh-based peer-to-peer streaming , 2006, NOSSDAV '06.

[3]  Lifeng Sun,et al.  Guyot: a hybrid learning- and model-based RTT predictive approach , 2015, 2015 IEEE International Conference on Communications (ICC).

[4]  Lifeng Sun,et al.  Optimizing the Throughput of Data-Driven Peer-to-Peer Streaming , 2009, IEEE Transactions on Parallel and Distributed Systems.

[5]  Lifeng Sun,et al.  Path-aware peer-assisted web content delivery against network failures , 2015, 2015 IEEE 23rd International Symposium on Quality of Service (IWQoS).

[6]  Michael Dahlin,et al.  End-to-end WAN service availability , 2001, TNET.

[7]  David Watson,et al.  Experiences with monitoring OSPF on a regional service provider network , 2003, 23rd International Conference on Distributed Computing Systems, 2003. Proceedings..

[8]  Feng Wang,et al.  Stable Peers: Existence, Importance, and Application in Peer-to-Peer Live Video Streaming , 2008, IEEE INFOCOM 2008 - The 27th Conference on Computer Communications.

[9]  Daniel Stutzbach,et al.  Understanding churn in peer-to-peer networks , 2006, IMC '06.

[10]  Lifeng Sun,et al.  CPCDN: Content Delivery Powered by Context and User Intelligence , 2015, IEEE Transactions on Multimedia.

[11]  Stefan Savage,et al.  California fault lines: understanding the causes and impact of network failures , 2010, SIGCOMM '10.

[12]  David Wetherall,et al.  Towards IP geolocation using delay and topology measurements , 2006, IMC '06.

[13]  Ravi Sundaram,et al.  WebCloud: Recruiting Social Network Users to Assist in Content Distribution , 2012, 2012 IEEE 11th International Symposium on Network Computing and Applications.

[14]  Ravi Sundaram,et al.  Maygh: building a CDN from client web browsers , 2013, EuroSys '13.

[15]  Michal Szymaniak,et al.  Replication for web hosting systems , 2004, CSUR.

[16]  William Chan,et al.  Improving Traffic Locality in BitTorrent via Biased Neighbor Selection , 2006, 26th IEEE International Conference on Distributed Computing Systems (ICDCS'06).