<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: arial,helvetica,sans-serif; font-size: 10pt; color: #000000'><div style="color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;"><span class="Apple-style-span" style="font-size: 13px; -webkit-tap-highlight-color: rgba(26, 26, 26, 0.296875); -webkit-composition-fill-color: rgba(175, 192, 227, 0.230469); -webkit-composition-frame-color: rgba(77, 128, 180, 0.230469); "><div>Soner Sevinc will present his preFPO on Thursday March 8 at 9AM in Room 402. <br>The members of his committee are: Larry Peterson, advisor; Jennifer Rexford <br>and Andy Bavier, readers; David Walker and Michael Freedman, nonreaders. <br>Everyone is invited to attend his talk. His abstract follows below.<br>-------------------------------------<br><br></div><div>Discovering and authorizing resources dispersed across autonomous organizations is a <br>challenge for federations as they scale. We introduce a delegation logic for federation to <br>address the problem of authentication and authorization in large scale. A Federation Policy <br>Language (FPL) is used to express this logic, and allows expression of custom security and <br>allocation policies. One distinguishing feature of FPL is that it utilizes a DHT for storage/retrieval <br>of certificates to increase fault-tolerance, efficiency and expressivity in proof constructions.</div><div class="im"><div>Our contract based discovery and allocation system, CODAL, performs policy-driven peer discovery <br>and collaborative resource discovery/allocation to address two problems: (1) participants in a <br>federation can be unknown, and (2) their resource information and policies can be private.</div></div><div class="im"><div>We evaluate our design in PlanetLab, emulating a realistic federation based on PlanetLab usage logs.</div><div>Results show that our system is capable of discovering and allocating resources in a large scale federation,</div><div>fulfilling a request from tens of organizations. We also show allocation policies are successfully <br>enforced by our language,and explore run-time characteristics of the FPL proof construction process, <br></div></div><div>and investigate certificate retrieval in terms of time and incurred system load.</div></span><div></div></div><br></div></body></html>