1. High Speed Networks Laboratory @ Budapest University of Technology and Economics http://hsnlab.tmit.bme.hu High Speed Networks Laboratory Monitoring Network Bias A joint project with Prof. Aleksandar Kuzmanovic (Northwestern University) Supported by NSF CAREER Award No. 0746360 Gergely Biczók PhD Candidate biczok@tmit.bme.hu

2. High Speed Networks Laboratory http://hsnlab.tmit.bme.hu | 2008-06-29 | FuturICT 20092 Outline Motivation: network neutrality Internet Audit System design Implementation Future work

3. High Speed Networks Laboratory http://hsnlab.tmit.bme.hu | 2008-06-29 | FuturICT 20093 Net neutrality: basics “… a network free of restrictions on equipment, modes of communication allowed, on content, sites, and platforms and where communication is not unreasonably degraded by other communication streams …” – Wikipedia Own definition: you get what you asked/paid for not less (e.g. blocking some websites) not more (e.g. ISP-embedded content to websites) Debate in public, struggle in legislation, war in the Internet Pro net neutrality: content providers (e.g., Google) and freedom activists www.savetheinternet.com Anti net neutrality: Internet Service Providers (with infrastructure, e.g., AT&T) http://www.handsoff.org/blog/

4. High Speed Networks Laboratory http://hsnlab.tmit.bme.hu | 2008-06-29 | FuturICT 20094 Net Neutrality: incentives and history (Access) ISPs have incentives to violate NN “Resource management” (Comcast) Potential side deals with content providers (AT&T) Larger profit through own proprietary services (blocking Skype in favor of own VoIP service) 2005: FCC enforcing net neutrality involving Madison River Communications that blocked Vonage VoIP 2006: China using Narus middleboxes to block Skype 2007: Comcast actively poisoning BitTorrent uploads 2008: YouTube outage, routing black hole caused by Pakistani ISP’s regulatory policy 2009: BitTorrent portals are blocked around the world 2005-: Rogers (Canada) blocks/shapes P2P, shapes all encrypted (!) traffic, forces users to its own SMTP servers, embed own content (!) into third-party webpages, … http://ihaterogers.ca

5. High Speed Networks Laboratory http://hsnlab.tmit.bme.hu | 2008-06-29 | FuturICT 20095 Internet Audit Goal: not to take sides in the net neutrality debate, but rather to design a system capable of making the Internet more transparent A distributed system to enable network accountability: What happened, where did it happen, and who is responsible? Challenges: Non-repudiable identification of discriminating network elements Detect unfair service favoring, e.g., content provider/ISP alliances Explore a range of threat models from open DoS attacks to using network policies in destructive ways First step: monitoring biased network behavior provide the users with information

6. High Speed Networks Laboratory http://hsnlab.tmit.bme.hu | 2008-06-29 | FuturICT 20096 Monitoring network bias An active measurement system which is Distributed Large-scale For all end-users Targeting access ISPs Capable of Detecting DPI, blocking, shaping, DNS hijacking, … Locating the discriminatory network element Finding out the subtype of biased behavior (e.g., shaping based on DPI vs. shaping) Provides an online service for end-users With feedback

7. High Speed Networks Laboratory http://hsnlab.tmit.bme.hu | 2008-06-29 | FuturICT 20097 System overview

8. High Speed Networks Laboratory http://hsnlab.tmit.bme.hu | 2008-06-29 | FuturICT 20098 Measurement methodology Collect reported/possible means of discrimination applied by ISPs Create active probes that likely trigger these mechanism We mostly emulate application/protocols e.g., BitTorrent-like traffic pattern without implementing a client Minimal user action is required Filtering Shaping (HTTP, FTP, SSL, BitTorrent) WWW bias (DNS hijacking, torrent portal blocking, …) Locating middleboxes By executing probes from multiple vantage points to the same end-host Correlating results Vantage point selection is critical (IP/geo, iPlane)

9. High Speed Networks Laboratory http://hsnlab.tmit.bme.hu | 2008-06-29 | FuturICT 20099 Filtering details Port-based Sending packets with random payload to well-defined ports Signature-based Deep Packet Inspection List of byte signatures for applications/protocols We derived a list based on open-source DPI: ipp2p, l7-filter protocol definitions own packet traces Flow-pattern based for P2P applications Header inspection plus spatial correlation of flows Random payload Data exchange: Parallel TCP connections from the same IP to several others in a port range Control: Parallel UDP connections from the same IP to different IPs to the same port With the correct order of probes the subtype can be determined

10. High Speed Networks Laboratory http://hsnlab.tmit.bme.hu | 2008-06-29 | FuturICT 200910 Implementation issues PlanetLab is widely used De facto standard test network Lot of users, slice-based access, ~20 active slices on one node Nodes go down at times M-Lab: dedicated to network transparency research Founded by: Open Technology Institute, Google, PlanetLab Consortium and researchers Administered by PlanetLab Limited number of users, ~1 slice per CPU core Ideal for active probing We are deploying our system to both platforms currently

11. High Speed Networks Laboratory http://hsnlab.tmit.bme.hu | 2008-06-29 | FuturICT 200911 Conduct a large-scale measurement campaign Evaluate and draw the global map of biased network behavior More on the Internet Audit project at http://networks.cs.northwestern.edu/internet-audit/ NetBias tool will be available at the M-Lab website soon http://www.measurementlab.net/ Future work Thank you for your attention!