Re: [p2pi] [p2prg] Mythbustering P2P traffic localization

Song Haibin <melodysong@huawei.com> Sat, 28 February 2009 07:47 UTC

Return-Path: <melodysong@huawei.com>
X-Original-To: p2pi@core3.amsl.com
Delivered-To: p2pi@core3.amsl.com
Received: from localhost (localhost [127.0.0.1]) by core3.amsl.com (Postfix) with ESMTP id 887553A698B; Fri, 27 Feb 2009 23:47:24 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.547
X-Spam-Level:
X-Spam-Status: No, score=-1.547 tagged_above=-999 required=5 tests=[AWL=1.052, BAYES_00=-2.599]
Received: from mail.ietf.org ([64.170.98.32]) by localhost (core3.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ihRgWNBJs8Ln; Fri, 27 Feb 2009 23:47:23 -0800 (PST)
Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [119.145.14.66]) by core3.amsl.com (Postfix) with ESMTP id 90E5F3A67E9; Fri, 27 Feb 2009 23:47:23 -0800 (PST)
Received: from huawei.com (szxga03-in [172.24.2.9]) by szxga03-in.huawei.com (iPlanet Messaging Server 5.2 HotFix 2.14 (built Aug 8 2006)) with ESMTP id <0KFR00F6TMZID4@szxga03-in.huawei.com>; Sat, 28 Feb 2009 15:47:42 +0800 (CST)
Received: from huawei.com ([172.24.1.33]) by szxga03-in.huawei.com (iPlanet Messaging Server 5.2 HotFix 2.14 (built Aug 8 2006)) with ESMTP id <0KFR00JZZMZI82@szxga03-in.huawei.com>; Sat, 28 Feb 2009 15:47:42 +0800 (CST)
Received: from s64081 ([10.164.12.16]) by szxml06-in.huawei.com (iPlanet Messaging Server 5.2 HotFix 2.14 (built Aug 8 2006)) with ESMTPA id <0KFR007CGMZHCR@szxml06-in.huawei.com>; Sat, 28 Feb 2009 15:47:42 +0800 (CST)
Date: Sat, 28 Feb 2009 15:47:41 +0800
From: Song Haibin <melodysong@huawei.com>
In-reply-to: <49A7C407.5080106@inria.fr>
To: 'Arnaud Legout' <arnaud.legout@inria.fr>, 'Enrico Marocco' <enrico.marocco@telecomitalia.it>
Message-id: <00c401c99978$d5dd38a0$100ca40a@china.huawei.com>
MIME-version: 1.0
X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.3350
X-Mailer: Microsoft Office Outlook 11
Content-type: text/plain; charset="us-ascii"
Content-transfer-encoding: 7bit
Thread-index: AcmYyIk7hQf0Th4lRHmzCaxjFquMEAArP7Kw
Cc: p2p-hackers@lists.zooko.com, p2pi@ietf.org, p2prg@irtf.org, alto@ietf.org
Subject: Re: [p2pi] [p2prg] Mythbustering P2P traffic localization
X-BeenThere: p2pi@ietf.org
X-Mailman-Version: 2.1.9
Precedence: list
List-Id: P2P Infrastructure Discussion <p2pi.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/listinfo/p2pi>, <mailto:p2pi-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/p2pi>
List-Post: <mailto:p2pi@ietf.org>
List-Help: <mailto:p2pi-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/p2pi>, <mailto:p2pi-request@ietf.org?subject=subscribe>
X-List-Received-Date: Sat, 28 Feb 2009 07:47:24 -0000

Hi Arnaud,

>section 8.2
>it is not clear what you mean in "as shown in [Le Blond], the right
>balance of randomness and
>  locality depends on the P2P algorithm". We did not explore several P2P
>protocols, but only BitTorrent.
>We show that BT is extremely robust to high locality (as long as there
>is enough randomness within each ISP).
>We cannot conclude for any other P2P protocol.

I guess if locality will weaken a swarm depends on in which proportion the
pieces of the resource the local peers have; and the balance of the cotent
pieces distribution among these local peers.

>"On the other hand, P2P systems not adopting the tit-for-tat approach
>  (e.g. the eDonkey network) should not be damaged by locality-based"
>It is not clear to me. Peer selection (tit-for-tat like choking algo in
>BT) is not the only one factor of efficiency, there is also piece
>diversity.
>Edonkey/emule also use rarest first (but a less efficient peer selection
>algorithm). Therefore, as locality adversely impact
>piece diversity, my bet is that Edonkey/emule will suffer from locality.

What do you mean with "less efficient" by saying "Edonkey/emule also use
rarest first (but a less efficient peer selection algorithm)"?

Regards,
Song Haibin