# [Busec] BUsec this week: Ben Fuller Tuesday 11AM, and Jennifer Rexford Friday 11AM

Sharon Goldberg goldbe at cs.bu.edu
Mon Mar 5 12:26:24 EST 2012

Hi All,

This week, we have our own Ben Fuller telling us about his TCC paper
with Leo Reyzin and Adam ONeill.  Tuesday 11AM in MCS148 (111
Cummington Street) , with lunch
served as usual.

Also, Jennifer Rexford is giving a distinguished colloquium at 11AM on
Friday in the Harriri Institute (111 Cummington Street) , abstract
below.  If you'd like
meeting with Jen during her visit, she'll be available from 3-4PM in
the security lab to chat informally with anyone who comes by.

Thanks!
Sharon

--
Sharon Goldberg
Computer Science, Boston University
http://www.cs.bu.edu/~goldbe

Ben Fuller. BU. A unified approach to deterministic encryption
When: Tue, March 6, 11am – 12pm

Abstract:

Public Key Encryption is a ubiquitous cryptographic tool.  A
randomized encryption algorithm is necessary to achieve semantic
security.  However, in several applications a deterministic encryption
algorithm is necessary or enables additional functionality.

In this talk, we present a general construction of deterministic
encryption schemes that unifies prior work and gives novel schemes. We
focus on a single message instantiation based on any trapdoor function
that has sufficiently many hardcore bits.  Our work also provides a
construction that achieves "bounded" multi-message security from lossy
trapdoor functions through a generalization of the leftover hash
lemma.  Our single message scheme is enabled by two tools that are of

- A weaker and more precise sufficient condition for "semantic"
security on a high-entropy message distribution. Namely, we show that
to establish "semantic" security on a distribution M of messages, it
suffices to establish indistinguishab​ility for all conditional
distribution M|E, where E is an event of probability at least 1/4.
(Prior work required indistinguishab​ility on all distributions of a
given entropy.)

- A result about computational entropy of conditional distributions.
Namely, we show that conditioning on an event E of probability p
reduces the quality of computational entropy by a factor of p and its
quantity by log_2 1/p.  We also extend our result about computational
entropy to the average case, which is useful in reasoning about
leakage-resilie​nt cryptography: leaking \lambda bits of information
reduces the quality of computational entropy by a factor of 2^\lambda
and its quantity by \lambda.

Joint work with Adam ONeill and Leo Reyzin.

*****

Friday, March 9, 2012
11:00 - 12:30 PM
The Hariri Institute Conference Room (MCS 180)
at 111 Cummington Street

Enabling Innovation Inside the Network
Jennifer Rexford
Princeton University

Abstract: Today's computer networks perform a bewildering array of
balancing.  Yet, network administrators must configure the network
through closed and proprietary interfaces to heterogeneous devices,
such as routers, switches, firewalls, and load balancers.  Not
surprisingly, configuring these complex networks is expensive and
error-prone, and innovation in network management proceeds at a
snail's pace.

During the past several years, the networking industry and research
community have pushed for greater openness in networking software, and
a clearer separation between networking devices and the software that
controls them. This broad trend is known as Software Defined
Networking (SDN).  A hallmark of SDN is having an open interface for
controller software running on a commodity computer to install
packet-processing rules in the underlying switches.  In particular,
many commercial switches support the OpenFlow protocol, and a number
of campus, data-center, and backbone networks have deployed the new
technology.

With the emergence of open interfaces to network devices, the time is
ripe to rethink the design of network software, to put the networking
field on a stronger foundation and foster innovation in networked
services.  Yet, while SDN makes it possible to program the network, it
does not make it easy.  After giving an overview of Software Defined
Networking, this talk discusses our Frenetic project that raises the
level of abstraction for programming the network.  We also outline
exciting opportunities for interdisciplinary research at the
intersection of programming languages and computer networks.

This is joint work with Nate Foster (Cornell), Dave Walker
(Princeton), Rob Harrison (US Military Academy), Chris Monsanto
(Princeton), Mark Reitblatt (Cornell), and Alec Story (Princeton),
Michael Freedman (Princeton), and Josh Reich (Princeton).

Bio: Jennifer Rexford is a Professor in the Computer Science
department at Princeton University.  From 1996-2004, she was a member
of the Network Management and Performance department at AT&T
Labs--Research.  Jennifer  is co-author of the book "Web Protocols and
Practice" (Addison-Wesley,  May 2001). She served as the chair of ACM
SIGCOMM from 2003 to 2007. Jennifer received her BSE degree in
electrical engineering from  Princeton University in 1991, and her MSE
and PhD degrees in computer science and electrical engineering from
the University of Michigan in 1993 and 1996, respectively.  She was
the 2004 winner of ACM's Grace Murray Hopper Award for outstanding
young computer professional.

Host: Sharon Goldberg