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Thai Duong
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Presenter: Dung Viet Nguyen (


Error correcting codes (ECC) are used to ensure reliable transmission of information. They are present in all digital communication systems, which are ubiquitous in our daily lives. The research on error correcting codes is multidisciplinary in its nature, and results are often found useful in many other areas. In this talk, I will give an overview on error correcting codes, focusing on some aspects which I think would be of most interest to the audience. Specifically, we will touch on the following:
-          The basic: Blocks of a digital communication system.

-          If you did not know what is ECC: The simplest examples of error correcting code.

-          To add excitement: What does it mean to have reliable transmission of information and is it possible?

-          To make it simple: A little bit of linear algebra and abstract algebra.

-          To make it beautiful: Maximum a posteriori and maximum likelihood.

-          To connect to search algorithms: Convolutional codes and the Viterbi algorithm.

-          To be modern: Low-density parity-check codes and message passing algorithms.

Other topics to discuss: trade-offs between reliability and bandwidth in Google and Facebook distributed storage.

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Presenter: Khai Q. Tran

My friends often ask me which database they should use for their
applications. It will depend on the requirements of their applications
and features that the database offers. In this talk, I would like to
discuss different types of databases and how they should be used. Then new trends about NoSQL and Big Data: SQL vs NoSQL, why needs NoSQL, CAP theorem, MPP vs MapReduce, SQL on Hadoop and SQL in Hadoop. Then if we still have time, I would like to do a deep dive on database internals, how to optimize and execute a SQL query.

I will try to make a few slides, but I prefer an open and interactive
discussion like the first infodump (so I can learn more from other
people :)).

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Topics: Juniper backdoors, random number generators, elliptic curve crypto, history of Dual EC, etc.


There are a lot of content, to make the most out of the tech talk please review the slides, takes notes if you have any questions.

You can start with juniper_backdoor.pdf, which was presented at a conference at Stanford just two weeks ago. The presentation should give you an overview of the two backdoors, their timelines, etc.

You can then move on to dual_ec_backdoor_1.pdf and dual_ec_backdoor_2.pdf which explain PRNG, the design of Dual EC, and its backdoor, and how to exploit it. Also check out and the research paper

The last slides deck is about the math behind everything. djb talked about it at CCC one or two years ago. You can watch the presentation at

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