Re: [dtn-interest] Hello from Brazil

<Tomaso.deCola@dlr.de> Mon, 03 February 2014 09:20 UTC

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From: <Tomaso.deCola@dlr.de>
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Thread-Topic: [dtn-interest] Hello from Brazil
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Date: Mon, 3 Feb 2014 09:19:46 +0000
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Marcelo,

Just to expand a bit on Keith's pointer, the erasure codes we developed here at DLR to work underneath LTP are conceived for large latencies and lossy channels (e.g., deep-space optical links), where the use of feedback-based recovery techniques is ineffective.
In any case, I think that  you should clarify what you mean by error correction and the specific technology being assumed (RF or optics). As to the former, actually, physical layer already implements channel coding schemes that already provide almost-error free conditions in some scenarios, whereby erasure codes is really meant to recover the "remaining" losses.

Best Regards,

Tomaso

------------------------
Deutsches Zentrum für Luft- und Raumfahrt (DLR)
German Aerospace Center
Institute of Communications and Navigation | Satellite Networks | Oberpfaffenhofen | 82234 Wessling | Germany
Tomaso de Cola, Ph.D.
Telefon +49 8153 28-2156 | Telefax  +49 8153 28-2844 | tomaso.decola@dlr.de<mailto:sandro.scalise@dlr.de>
http://www.dlr.de/kn/institut/abteilungen/san

From: dtn-interest [mailto:dtn-interest-bounces@irtf.org] On Behalf Of Prof. Marcelo
Sent: Friday, January 31, 2014 5:57 PM
Cc: dtn-interest@irtf.org
Subject: Re: [dtn-interest] Hello from Brazil

Hi Keith, thanks for your replay. I will take a look this documents.

hugs!

2014-01-31 Scott, Keith L. <kscott@mitre.org<mailto:kscott@mitre.org>>:
Marcelo,

Tomaso deCola from DLR has done some work with forward erasure coding underneath the Licklider Transmission Protocol (LTP), one of the 'convergence layers' underneath the DTN Bundle Protocol.  One of his more recent briefings on the topic is on the CCSDS Collaborative Work Environment (CWE) at http://cwe.ccsds.org/sis/docs/SIS-DTN/Meeting%20Materials/2013/Fall%20--%20San%20Antonio/LTP_w_EC.pdf

In terms of security protocol work, the IRTF is working to revise the Bundle Security Protocol to produce a 'streamlined bundle security protocol'; the informational draft is available at http://tools.ietf.org/html/draft-irtf-dtnrg-sbsp-00.

                        Best regards,

                        --keith



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From: dtn-interest [mailto:dtn-interest-bounces@irtf.org<mailto:dtn-interest-bounces@irtf.org>] On Behalf Of Prof. Marcelo
Sent: Friday, January 31, 2014 7:14 AM
To: dtn-interest@irtf.org<mailto:dtn-interest@irtf.org>
Subject: [dtn-interest] Hello from Brazil

Hello Everybody, how are you?

My name is Marcelo Guido, and I'm from Brazil. I study at UNIFESP (Federal University of Sao Paulo). For my master degree i´m studing the security of DTN's. I read some papers, like Ivancic (2010 - Security Analysis of DTN Architecture and Bundle Protocol Specification for Space-Based Networks), Ntareme and Domancich (2011 - Security and performance aspects of Bytewalla: A Delay Tolerant Network on smartphones). Now I´m reading the paper of Wood, Eddy and Holliday (2009 - A Bundle of Problems.

I found this subject very interesting. In a meeting with my guiding, we talk about the question of error correction. Some of you are researching on this area of knowledge? Is this a promising area of research?

Sorry by terrible english...:-)

Hugs!
Marcelo Guido