99,171 research outputs found
Private Data Transfer over a Broadcast Channel
We study the following private data transfer problem: Alice has a database of
files. Bob and Cathy want to access a file each from this database (which may
or may not be the same file), but each of them wants to ensure that their
choices of file do not get revealed even if Alice colludes with the other user.
Alice, on the other hand, wants to make sure that each of Bob and Cathy does
not learn any more information from the database than the files they demand
(the identities of which will be unknown to her). Moreover, they should not
learn any information about the other files even if they collude.
It turns out that it is impossible to accomplish this if Alice, Bob, and
Cathy have access only to private randomness and noiseless communication links.
We consider this problem when a binary erasure broadcast channel with
independent erasures is available from Alice to Bob and Cathy in addition to a
noiseless public discussion channel. We study the
file-length-per-broadcast-channel-use rate in the honest-but-curious model. We
focus on the case when the database consists of two files, and obtain the
optimal rate. We then extend to the case of larger databases, and give upper
and lower bounds on the optimal rate.Comment: To be presented at IEEE International Symposium on Information Theory
(ISIT 2015), Hong Kon
Multi-Gigabit Wireless data transfer at 60 GHz
In this paper we describe the status of the first prototype of the 60 GHz
wireless Multi-gigabit data transfer topology currently under development at
University of Heidelberg using IBM 130 nm SiGe HBT BiCMOS technology. The 60
GHz band is very suitable for high data rate and short distance applications as
for example needed in the HEP experments. The wireless transceiver consist of a
transmitter and a receiver. The transmitter includes an On-Off Keying (OOK)
modulator, an Local Oscillator (LO), a Power Amplifier (PA) and a BandPass
Filter (BPF). The receiver part is composed of a BandPass- Filter (BPF), a Low
Noise Amplifier (LNA), a double balanced down-convert Gilbert mixer, a Local
Oscillator (LO), then a BPF to remove the mixer introduced noise, an
Intermediate Amplifier (IF), an On-Off Keying demodulator and a limiting
amplifier. The first prototype would be able to handle a data-rate of about 3.5
Gbps over a link distance of 1 m. The first simulations of the LNA show that a
Noise Figure (NF) of 5 dB, a power gain of 21 dB at 60 GHz with a 3 dB
bandwidth of more than 20 GHz with a power consumption 11 mW are achieved.
Simulations of the PA show an output referred compression point P1dB of 19.7 dB
at 60 GHz.Comment: Proceedings of the WIT201
High-speed data transfer with FPGAs and QSFP+ modules
We present test results and characterization of a data transmission system
based on a last generation FPGA and a commercial QSFP+ (Quad Small Form
Pluggable +) module. QSFP+ standard defines a hot-pluggable transceiver
available in copper or optical cable assemblies for an aggregated bandwidth of
up to 40 Gbps. We implemented a complete testbench based on a commercial
development card mounting an Altera Stratix IV FPGA with 24 serial transceivers
at 8.5 Gbps, together with a custom mezzanine hosting three QSFP+ modules. We
present test results and signal integrity measurements up to an aggregated
bandwidth of 12 Gbps.Comment: 5 pages, 3 figures, Published on JINST Journal of Instrumentation
proceedings of Topical Workshop on Electronics for Particle Physics 2010,
20-24 September 2010, Aachen, Germany(R Ammendola et al 2010 JINST 5 C12019
Computer/computer interface
System synchronizes data transfer between two computers by generating data strobe pulses when computers are ready for data transfer. In addition, interface filters noise by sampling
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