# Colloquia and Seminars

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## Upcoming Colloquia & Seminars

• ### Haifux Club: Bitcoin - What and Why

Speaker:
Daniel Brunstein
Date:
Monday, 27.10.2014, 18:30
Place:
Taub 2

A lecture with a life demo!

General Agenda

• What is Bitcoin
• Wallets (mobile, cloud, cold storage)
• Price and Market Capacitance
• Worldwide adoption by big corporations and merchants
• Regulatory environment
• Billion Dollar Markets being disrupted by Bitcoin
• Alternative crypto-currencies and Bitcoin 2.0
• VC investment in Bitcoin startups
• Bitcoin in Israel
• Bitcoin in the Academy

Technical Agenda

• Public/private keys
• Mining
• Blockchain
• Security, 51% attack

• ### ceClub: Enabling Peer-to-Peer Swarming for Multi-commodity Dissemination

Speaker:
Daniel Sadoc Menasche (Federal University of Rio de Janeiro)
Date:
Wednesday, 29.10.2014, 11:30
Place:
EE Meyer Building TBA

Peer-to-peer swarming, as used by BitTorrent, is one of the \emph{de facto} solutions for content dissemination in today's Internet. By leveraging resources provided by users, peer-to-peer swarming is a simple, scalable and efficient mechanism for content distribution. Although peer-to-peer swarming has been widely studied for a decade, prior work has focused on the dissemination of one commodity (a single file). This work focuses on the multi-commodity case.

We have discovered through measurements that a vast number of publishers currently disseminate multiple files in a single swarm (bundle). The first contribution of this work is a model for content availability. We use the model to show that, when publishers are intermittent, bundling $K$ files increases content availability exponentially as function of $K$. When there is a stable publisher, we consider content availability among peers (excluding the publisher). Our second contribution is the estimate of the dependency of peers on the stable publisher, which is useful for provisioning purposes as well as in deciding how to bundle. To this goal, we propose a new metric, swarm self-sustainability, and present a model that yields swarm self-sustainability as a function of the file size, popularity and service capacity of peers. Then, we investigate reciprocity and the use of barter that occurs among peers. As our third contribution, we prove that the loss of efficiency due to the download of unrequested content to enforce direct reciprocity, as opposed to indirect reciprocity, is at most two in a class of networks without relays.

Bio:
Daniel S. Menasche received his Ph.D. in computer science from the University of Massachusetts at Amherst in 2011. Currently, he is an Assistant Professor in the Computer Science Department at the Federal University of Rio de Janeiro, Brazil. His interests are in modeling, analysis and performance evaluation of computer systems. He was awarded the Yahoo! outstanding synthesis project award at UMass in 2010. He was also co-author of papers that received best paper awards at Globecom’07, CoNEXT’09 and INFOCOM'13. CeClub website: http://ceclub.technion.ac.il

• ### CGGC Seminar: Topologically Guaranteed Bivariate Solutions Of Under-Constrained Multivariate Piecewise Polynomial Systems

Speaker:
Yoni Mizrachi (CS, Technion)
Date:
Sunday, 2.11.2014, 14:30
Place:
Taub 401

We present a subdivision based algorithm to compute the solution of an under-constrained piecewise polynomial system of n−2 equations with n unknowns, exploiting properties of B-spline basis functions. The solution of such systems is, typically, a two-manifold in R^n. To guarantee the topology of the approximated solution in each sub-domain, we provide subdivision termination criteria, based on the (known) topology of the univariate solution on the domain’s boundary, and the existence of a one-to-one projection of the unknown solution on a two dimensional plane, in R^n. We assume the equation solving problem is regular, while sub-domains containing points that violate the regularity assumption are detected, bounded, and returned as singular locations of small (subdivision tolerance) size. This work extends (and makes extensive use of) topological guarantee results for systems with zero and one dimensional solution sets. Test results in R^3 and R^4 are also demonstrated, using error-bounded piecewise linear approximations of the two-manifolds.

• ### Robust Probabilistic Inference

Speaker:
Yishay Mansour - Colloquium Lecture
Date:
Tuesday, 4.11.2014, 14:30
Place:
Room 337-8 Taub Bld.
Link:
http://www.cs.technion.ac.il/~colloq/20141104_14_30_Mansour.html
• ### When Machines Dominate Humans: The Challenges of Mining and Consuming Machine-generated Web Mail

Speaker:
Yoelle Maarek - Colloquium Lecture
Date:
Tuesday, 11.11.2014, 14:30
Place:
Room 337-8 Taub Bld.
Link:
http://www.cs.technion.ac.il/~colloq/20141111_14_30_Maarek.html
• ### The Axiomatic Approach and the Internet

Speaker:
Moshe Tennenholtz - Colloquium Lecture
Date:
Tuesday, 18.11.2014, 14:30
Place:
Room 337-8 Taub Bld.
Link:
http://www.cs.technion.ac.il/~colloq/20141118_14_30_Tennenholz.html
• ### The Cryptographic Lens

Speaker:
Shafi Goldwasser - Colloquium Lecture
Date:
Tuesday, 9.12.2014, 14:30
Place:
Room 337-8 Taub Bld.
Link:
http://www.cs.technion.ac.il/~colloq/20141209_14_30_Goldwasser.html