From vkg@bell-labs.com Mon May 2 06:40:16 2011 Return-Path: X-Original-To: p2prg@ietfa.amsl.com Delivered-To: p2prg@ietfa.amsl.com Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 3C54EE0688; Mon, 2 May 2011 06:40:16 -0700 (PDT) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -104.885 X-Spam-Level: X-Spam-Status: No, score=-104.885 tagged_above=-999 required=5 tests=[AWL=1.714, BAYES_00=-2.599, RCVD_IN_DNSWL_MED=-4, USER_IN_WHITELIST=-100] Received: from mail.ietf.org ([64.170.98.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 5nLzZvsSUZsU; Mon, 2 May 2011 06:40:15 -0700 (PDT) Received: from ihemail3.lucent.com (ihemail3.lucent.com [135.245.0.37]) by ietfa.amsl.com (Postfix) with ESMTP id 876E5E0678; Mon, 2 May 2011 06:40:15 -0700 (PDT) Received: from usnavsmail2.ndc.alcatel-lucent.com (usnavsmail2.ndc.alcatel-lucent.com [135.3.39.10]) by ihemail3.lucent.com (8.13.8/IER-o) with ESMTP id p42DeDKu017338 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Mon, 2 May 2011 08:40:13 -0500 (CDT) Received: from umail.lucent.com (umail-ce2.ndc.lucent.com [135.3.40.63]) by usnavsmail2.ndc.alcatel-lucent.com (8.14.3/8.14.3/GMO) with ESMTP id p42DeCYP027416 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Mon, 2 May 2011 08:40:13 -0500 Received: from shoonya.ih.lucent.com (shoonya.ih.lucent.com [135.185.238.233]) by umail.lucent.com (8.13.8/TPES) with ESMTP id p42DeAWG028083; Mon, 2 May 2011 08:40:11 -0500 (CDT) Message-ID: <4DBEB4C2.3040700@bell-labs.com> Date: Mon, 02 May 2011 08:42:26 -0500 From: "Vijay K. Gurbani" Organization: Bell Laboratories, Alcatel-Lucent User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.15) Gecko/20110307 Fedora/3.1.9-0.39.b3pre.fc14 Thunderbird/3.1.9 MIME-Version: 1.0 To: Richard Alimi References: <4DA875CA.4010505@bell-labs.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.57 on 135.245.2.37 X-Scanned-By: MIMEDefang 2.64 on 135.3.39.10 Cc: "p2prg@irtf.org" , alto Subject: Re: [p2prg] [alto] ns-3/ALTO: Influencing suboptimal peer selection X-BeenThere: p2prg@irtf.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Peer-to-Peer Research Group List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 02 May 2011 13:40:16 -0000 On 04/30/2011 11:10 AM, Richard Alimi wrote: > Very interesting results! It does look like it converges to a good > result, but I'm wondering if it would be possible to reduce the > convergence time further (smaller than 10m). Can you give some more > details on how ALTO was integrated with the BitTorrent clients here? Rich: Sure. Please see inline. > Was it used for ranking peers returned from a tracker, or also > peer-exchange (if enabled)? We have not implemented peer-exchange in our ns-3 model. So, the results you see are only from getting the peer list from a tracker. > How often were new peers discovered from a tracker or peer-exchange? A peer in our model contacts the tracker every 30s of simulated time. > Was it a greedy strategy in which only closest peers were chosen, or > were a few sub-optimal peers chosen for robustness? For starters, the peer list returned by the tracker is not modified to remove any peers; the peer list is simply re-ordered with the least desirable peers appearing at the bottom of the list. The announcing peer gets this list from the ALTO server and starts to contact each peer in the list starting from the top of the list, subject to the constraints that: (a) it may already have an existing connection with that peer, so no point in establishing a new one; (b) the contacted peer may not accept the announcing peer's connection request; (c) the contacted peer may accept the announcing peer's request, but choke it until further notice; Thus, a few sub-optimal peers will sneak depending on the constraints outlined above. I have not done an analysis on output of the simulation to see what is the distribution of the connections between an announcing peer to sub-optimal peers, but intuitively, it appears that there will be a minority of suboptimal peers. Thanks, - vijay -- Vijay K. Gurbani, Bell Laboratories, Alcatel-Lucent 1960 Lucent Lane, Rm. 9C-533, Naperville, Illinois 60566 (USA) Email: vkg@{bell-labs.com,acm.org} / vijay.gurbani@alcatel-lucent.com Web: http://ect.bell-labs.com/who/vkg/ From arnaud.legout@inria.fr Thu May 5 05:07:54 2011 Return-Path: X-Original-To: p2prg@ietfa.amsl.com Delivered-To: p2prg@ietfa.amsl.com Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 6097CE0770 for ; Thu, 5 May 2011 05:07:54 -0700 (PDT) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -7.504 X-Spam-Level: X-Spam-Status: No, score=-7.504 tagged_above=-999 required=5 tests=[AWL=2.745, BAYES_00=-2.599, HELO_EQ_FR=0.35, RCVD_IN_DNSWL_HI=-8] Received: from mail.ietf.org ([64.170.98.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id UEVzyf-C4QlB for ; Thu, 5 May 2011 05:07:53 -0700 (PDT) Received: from mail3-relais-sop.national.inria.fr (mail3-relais-sop.national.inria.fr [192.134.164.104]) by ietfa.amsl.com (Postfix) with ESMTP id 302EEE076D for ; Thu, 5 May 2011 05:07:52 -0700 (PDT) X-IronPort-AV: E=Sophos;i="4.64,319,1301868000"; d="scan'208";a="82413477" Received: from arnaud09.inria.fr (HELO [138.96.198.246]) ([138.96.198.246]) by mail3-relais-sop.national.inria.fr with ESMTP/TLS/DHE-RSA-CAMELLIA256-SHA; 05 May 2011 14:07:50 +0200 Message-ID: <4DC29317.1090002@inria.fr> Date: Thu, 05 May 2011 14:07:51 +0200 From: Arnaud Legout User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.15) Gecko/20110303 Thunderbird/3.1.9 MIME-Version: 1.0 To: "Vijay K. Gurbani" References: <4DA875CA.4010505@bell-labs.com> In-Reply-To: <4DA875CA.4010505@bell-labs.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: "p2prg@irtf.org" , alto Subject: Re: [p2prg] [alto] ns-3/ALTO: Influencing suboptimal peer selection X-BeenThere: p2prg@irtf.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Peer-to-Peer Research Group List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 05 May 2011 12:07:54 -0000 Hi, On 15/04/2011 18:43, Vijay K. Gurbani wrote: > One issue that has been talked about in ALTO is whether it can > influence the choice of sub-optimal peers; in other words, > can ALTO be used to purposely provide sub-optimal peers simply > because a peering relationship exists and the peers in the > peering network are sub-optimal (i.e., they may have less upload > bandwidth when compared to other peers). > > The third simulation shows that this is not the case, and other > publications [2] have experimentally demonstrated that this > is not the case for BitTorrent at least. BitTorrent exhibits > strong clustering behaviour, where similar-bandwidth peers > cluster together to ensure effective sharing incentives by > rewarding peers who contribute proportionally more to the > system. what we have done in [2] is in the context of no constraint on the interconnexion graph among peers. We studied in [3] the case of a constrained graph (used to enforce locality). I believe [3] is more relevant to the discussion, as it shows that even with a very constrained graph, BitTorrent is still quite efficient. However, we didn't looked at the clustering properties with a constrained graph in [3]. From [2], I am convinced that if the incoming rate of new pieces in a given ISP is lower than the upload rate of the fast uploading leechers in that ISP, it is likely that clustering and sharing incentives will not hold anymore. The lack of sharing incentives might be a real issue. For this reason, it is certainly a good idea to use fast uploading leechers as bridges among ISPs so that each of those leechers can act as fast surrogate feeds for new pieces. In that case, clustering and sharing incentives will still hold. All my reasoning is in case of torrents that are starting (many leechers, one seed). As long as there are enough seeds, the sharing incentive property is less important. Regards, Arnaud. > [2] "Clustering and sharing incentives in BitTorrent systems", > Arnaud Legout, Nikitas Liogkas, Eddie Kohler and Lixia Zhang, > ACM Sigmetrics, June 2007. [3] Stevens Le Blond, Arnaud Legout, Walid Dabbous. Pushing BitTorrent Locality to the Limit. Computer Networks, doi:10.1016/j.comnet.2010.09.014, 2010. From chinaliulu@hotmail.com Fri May 20 08:44:39 2011 Return-Path: X-Original-To: p2prg@ietfa.amsl.com Delivered-To: p2prg@ietfa.amsl.com Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 109E1E066A for ; Fri, 20 May 2011 08:44:39 -0700 (PDT) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -0.184 X-Spam-Level: X-Spam-Status: No, score=-0.184 tagged_above=-999 required=5 tests=[BAYES_40=-0.185, HTML_MESSAGE=0.001] Received: from mail.ietf.org ([64.170.98.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id V66-nSzL-lKc for ; Fri, 20 May 2011 08:44:37 -0700 (PDT) Received: from blu0-omc4-s15.blu0.hotmail.com (blu0-omc4-s15.blu0.hotmail.com [65.55.111.154]) by ietfa.amsl.com (Postfix) with ESMTP id E450BE0651 for ; Fri, 20 May 2011 08:44:36 -0700 (PDT) Received: from BLU154-W38 ([65.55.111.136]) by blu0-omc4-s15.blu0.hotmail.com with Microsoft SMTPSVC(6.0.3790.4675); Fri, 20 May 2011 08:44:35 -0700 Message-ID: Content-Type: multipart/alternative; boundary="_33c3b08a-7031-474c-8c7d-9217b0da54b5_" X-Originating-IP: [195.194.178.251] From: Lu Liu To: Date: Fri, 20 May 2011 15:44:35 +0000 Importance: Normal In-Reply-To: References: MIME-Version: 1.0 X-OriginalArrivalTime: 20 May 2011 15:44:35.0779 (UTC) FILETIME=[D2059130:01CC1704] Subject: [p2prg] CFA: 10th e-Science All Hands Meeting, York, UK X-BeenThere: p2prg@irtf.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Peer-to-Peer Research Group List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 20 May 2011 15:44:39 -0000 --_33c3b08a-7031-474c-8c7d-9217b0da54b5_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable 10th e-Science All Hands Meeting=2C York=2C UK ---------------------------------------------------------------------- Website: http://www.allhands.org.uk =20 Call for Abstracts --------------------- The tenth e-Science All Hands Meeting (AHM) will be held from 26th-29th Sep= tember 2011=2C in the historic city of York=2C United Kingdom. The conferen= ce will feature keynote presentations=2C workshop sessions=2C poster presen= tations and demonstrations=2C from the domains of e-Science=2C e-Social sci= ence and the arts and humanities. Authors are invited to submit abstracts of unpublished=2C original work of = not more than 3 pages in length to AHM=FF2011 themes and workshops=2C using= single spaced 10 point size on A4 pages - including 2 pages of text and (optionally) 1 page of figures and tables. Authors are to submit abstracts = satisfying the Formatting Guidelines as a PDF file using the AHM 2011 Abstr= act Submission system. =20 Submission to Themes --------------------------- Authors are asked to submit to one of the following themes or as a 'general= paper': =20 * Theme 1: Cloud computing for e-Research * Theme 2: Shared Infrastructures=2C Systems and Tools for e-Research * Theme 3: Applications and end-user engagement in e-Research * Theme 4: Data-intensive Research * Theme 5: Organisation=2C Trust=2C Security and Validation * General Paper =20 All themes are applicable to the domains of e-Science=2C e-Social Science= =2C and the arts and humanities. This year=2C we especially encourage indus= try collaborators to engage fully in the conference (we will shortly be inc= luding information on the website detailing Exhibit and Sponsorship opportu= nities)=2C including contributing to papers. As in previous years=2C authors of selected abstracts will be invited to su= bmit full papers (after AHM 2011) to be considered for inclusion in a speci= al edition of a journal (to be confirmed). It should be noted that conferen= ce proceedings will not be published. =20 Workshops and Tutorials ------------------------------ =20 The 2011 All Hands Meeting has scheduled time for a limited number of half = day workshops. Interested parties may submit proposals for workshops (1 A4 = page) to tom.jackson@cs.york.ac.uk. The deadline for workshop proposals is = 22nd April 2011. Important Dates: ---------------- 6 June 2011 - The deadline for abstract submissions 25 July 2011 - Decisions to authors. =20 Website: http://www.allhands.org.uk = --_33c3b08a-7031-474c-8c7d-9217b0da54b5_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
10th e-Science All Hands Meeting=2C York=2C UK

-----------------= -----------------------------------------------------

Website: = =3B http://www.allhands.org.uk

 =3B

Call for Abstracts
---------------------
The tenth e-Science All Hands Meeting (AHM) w= ill be held from 26th-29th September 2011=2C in the historic city of York= =2C United Kingdom. The conference will feature keynote presentations=2C wo= rkshop sessions=2C poster presentations and demonstrations=2C from the doma= ins of e-Science=2C e-Social science and the arts and humanities.

Au= thors are invited to submit abstracts of unpublished=2C original work of no= t more than 3 pages in length to AHM=FF2011 themes and workshops=2C using s= ingle spaced 10 point size on A4 pages - including 2 pages of text and
<= br>(optionally) 1 page of figures and tables. Authors are to submit abstrac= ts satisfying the Formatting Guidelines as a PDF file using the AHM 2011 Ab= stract Submission system.

 =3B
Submission to Themes
-----= ----------------------


Authors are asked to submit to one of the= following themes or as a 'general paper':

 =3B

* Theme 1= : Cloud computing for e-Research

* Theme 2: Shared Infrastructures= =2C Systems and Tools for e-Research

* Theme 3: Applications and end= -user engagement in e-Research

* Theme 4: Data-intensive Research
* Theme 5: Organisation=2C Trust=2C Security and Validation

* G= eneral Paper

 =3B

All themes are applicable to the domain= s of e-Science=2C e-Social Science=2C and the arts and humanities. This yea= r=2C we especially encourage industry collaborators to engage fully in the = conference (we will shortly be including information on the website detaili= ng Exhibit and Sponsorship opportunities)=2C including contributing to pape= rs.

As in previous years=2C authors of selected abstracts will be in= vited to submit full papers (after AHM 2011) to be considered for inclusion= in a special edition of a journal (to be confirmed). It should be noted th= at conference proceedings will not be published.

 =3B

Wor= kshops and Tutorials

------------------------------

 =3B<= br>The 2011 All Hands Meeting has scheduled time for a limited number of ha= lf day workshops. Interested parties may submit proposals for workshops (1 = A4 page) to tom.jackson@cs.york.ac.uk. The deadline for workshop proposals = is 22nd April 2011.




Important Dates:

------------= ----


6 June 2011 =3B - The deadline for abstract submissions=
25 July 2011 - Decisions to authors.

 =3B

Website:&nb= sp=3B http://www.allhands.org.uk
= --_33c3b08a-7031-474c-8c7d-9217b0da54b5_--