Re: [alto] Pub-sub interfaces

"Y. Richard Yang" <yry@cs.yale.edu> Tue, 31 December 2013 02:05 UTC

Return-Path: <yang.r.yang@gmail.com>
X-Original-To: alto@ietfa.amsl.com
Delivered-To: alto@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id D35B61AE367 for <alto@ietfa.amsl.com>; Mon, 30 Dec 2013 18:05:32 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: 0.622
X-Spam-Level:
X-Spam-Status: No, score=0.622 tagged_above=-999 required=5 tests=[BAYES_20=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, FM_FORGED_GMAIL=0.622, FREEMAIL_FROM=0.001, HTML_MESSAGE=0.001, SPF_PASS=-0.001] autolearn=no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id jR266RmMsTOd for <alto@ietfa.amsl.com>; Mon, 30 Dec 2013 18:05:31 -0800 (PST)
Received: from mail-pb0-x22e.google.com (mail-pb0-x22e.google.com [IPv6:2607:f8b0:400e:c01::22e]) by ietfa.amsl.com (Postfix) with ESMTP id 001501AE2BD for <alto@ietf.org>; Mon, 30 Dec 2013 18:05:30 -0800 (PST)
Received: by mail-pb0-f46.google.com with SMTP id md12so12069045pbc.19 for <alto@ietf.org>; Mon, 30 Dec 2013 18:05:25 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=gYrYhZwzlr/UwhfUWj0OHtS5dHQpAMjHN03Me2eHG1M=; b=ZdSqVipJHm7yqw2DgHMTSIfYRqpB71rQKcksBnFzg96UlQ4hWIuM66fNYyd/W55NLM ddV2W6jChNeyWEkBjfEQhhR9RlF5g6NzWT7NMSshjmkPyo7pITJGt3tnZjmaHb/XMmS7 L9Y0vjkGoTVW5nCGtSflgEiWHVkkVbQtBF8IfF1O1zXTQ07KlRdzfYt4prnumLnOq1DE QG5vn5v+oclS+5cuG6HIGgbX0R9RBkL8kBLNd4TXIKbTGAkhwdl/oBrXl+rwXJhk7VjV dcRjYeq8ndCf2+CBe3PRsh2NQ218y8tMor9pUWhra5BnvPQFa0pLXnDejANcxsOhC0Iz eaKw==
MIME-Version: 1.0
X-Received: by 10.68.29.72 with SMTP id i8mr73410549pbh.116.1388455524890; Mon, 30 Dec 2013 18:05:24 -0800 (PST)
Sender: yang.r.yang@gmail.com
Received: by 10.68.106.193 with HTTP; Mon, 30 Dec 2013 18:05:24 -0800 (PST)
In-Reply-To: <4DFA6345-8D80-4205-B1A7-C91FDF15AA1C@tid.es>
References: <4DFA6345-8D80-4205-B1A7-C91FDF15AA1C@tid.es>
Date: Mon, 30 Dec 2013 21:05:24 -0500
X-Google-Sender-Auth: JE88qEra5jGXq7CUiOzd97UU4xw
Message-ID: <CANUuoLp6n-=Fedktn0Bbb9D6kxkUWZUNt9AiSiRpc5nsC5+dcg@mail.gmail.com>
From: "Y. Richard Yang" <yry@cs.yale.edu>
To: "Diego R. Lopez" <diego@tid.es>
Content-Type: multipart/alternative; boundary="bcaec52160c959027704eecafe98"
Cc: "alto@ietf.org ALTO" <alto@ietf.org>
Subject: Re: [alto] Pub-sub interfaces
X-BeenThere: alto@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: "Application-Layer Traffic Optimization \(alto\) WG mailing list" <alto.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/alto>, <mailto:alto-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/alto/>
List-Post: <mailto:alto@ietf.org>
List-Help: <mailto:alto-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/alto>, <mailto:alto-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 31 Dec 2013 02:05:33 -0000

Hi Diego,

Thanks a lot for posting the link. I read the document and it was a
well-written document. If the document provides more text to review the two
pub-sub models and how they may apply to I2RS, it will be more
self-contained.

A key proposal from the document, I see, is the introduction of a Message
Broker. A main motivation appears to be scalability, i.e., to avoid the P *
S problem, where P is the number of publishers and S the number of
subscribers.

One problem of the document is that it appears to be quite broad, where
either applications or routers can publish and subscribe (not sure if
routers will subscribe though), and many types (e.g., router/device status
changes, app info changes? policy changes) are mentioned. This may imply
that the schema of the pub-sub system can be quite complex or very generic.
We know generic, well-used systems such as Google Chabby (Zookeeper), and
hence I will wait to see the details of any specific proposals, on whether
they will apply to ALTO. A concrete issue that I will look for is on how to
encode updates of a large data set, e.g., a Network/Cost Map.

As a simple, related use case of their scheme, an ALTO Server can be a
publisher to push any incremental updates to the Media Broker, who can then
handle a large number of subscribers. More complicated use cases or ALTO
should develop its own sub-pub mechanism?

Happy New Year!

Richard




On Fri, Dec 27, 2013 at 10:58 AM, Diego R. Lopez <diego@tid.es> wrote:

> Hi,
>
> Some time ago we discussed about the pros and cons of using Websockets for
> implementing server-to-client notifications and I mentioned the possibility
> of using a pub-sub schema for creating a general notification framework.
>
> While reviewing some messages during my end-of-year tidying I came through
> this draft:
> http://tools.ietf.org/html/draft-camwinget-i2rs-pubsub-sec-00
> contributed to I2RS, that discusses the application of the model in the
> access to a programmatic interface to the routing system. I think it
> provides a good overview of the model, and that many of the considerations
> are applicable to ALTO notifications, and even more to a generalized
> topology service.
>
> Be goode,
>
> --
> "Esta vez no fallaremos, Doctor Infierno"
>
> Dr Diego R. Lopez
> Telefonica I+D
> http://people.tid.es/diego.lopez/
>
> e-mail: diego@tid.es
> Tel:    +34 913 129 041
> Mobile: +34 682 051 091
> -----------------------------------------
>
>
> ________________________________
>
> Este mensaje se dirige exclusivamente a su destinatario. Puede consultar
> nuestra política de envío y recepción de correo electrónico en el enlace
> situado más abajo.
> This message is intended exclusively for its addressee. We only send and
> receive email on the basis of the terms set out at:
> http://www.tid.es/ES/PAGINAS/disclaimer.aspx
> _______________________________________________
> alto mailing list
> alto@ietf.org
> https://www.ietf.org/mailman/listinfo/alto
>



-- 
-- 
 =====================================
| Y. Richard Yang <yry@cs.yale.edu>   |
| Professor of Computer Science       |
| http://www.cs.yale.edu/~yry/        |
 =====================================