Re: [nbs] Name->Locator validation. (Was: Re: A suggestion for an "on-demand API".)

Brian E Carpenter <> Tue, 21 December 2010 19:36 UTC

Return-Path: <>
Received: from localhost (localhost []) by (Postfix) with ESMTP id 4A4643A6B47 for <>; Tue, 21 Dec 2010 11:36:32 -0800 (PST)
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: NO
X-Spam-Score: -103.374
X-Spam-Status: No, score=-103.374 tagged_above=-999 required=5 tests=[AWL=0.225, BAYES_00=-2.599, RCVD_IN_DNSWL_LOW=-1, USER_IN_WHITELIST=-100]
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id w-JaEIFJwznK for <>; Tue, 21 Dec 2010 11:36:31 -0800 (PST)
Received: from ( []) by (Postfix) with ESMTP id 2E1623A6866 for <>; Tue, 21 Dec 2010 11:36:31 -0800 (PST)
Received: by wyf23 with SMTP id 23so4361734wyf.31 for <>; Tue, 21 Dec 2010 11:38:27 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;; s=gamma; h=domainkey-signature:received:received:message-id:date:from :organization:user-agent:mime-version:to:cc:subject:references :in-reply-to:content-type:content-transfer-encoding; bh=mdVVYPwkb3Nb95VWL2tZAusB3hCKwnmiP+Wd/eNkoYw=; b=a+qDh/XKlol+5dRXQmsmOVH0U37KOVfRaYYYxl18HXw1wOtp5TCxwNTui3XhBnehEc KZpo7TPbUnFJVwI4dKVTaQO8xfrESKd1Bae4zCVVHJSmaTSXaMU9Tid6N6PpahBHqPex BTXs+qlmTyINfcdc3I8LfwBFadf3m53P/eStg=
DomainKey-Signature: a=rsa-sha1; c=nofws;; s=gamma; h=message-id:date:from:organization:user-agent:mime-version:to:cc :subject:references:in-reply-to:content-type :content-transfer-encoding; b=Uj5vpFmCyaa5Ay8Gtiwez2NHmyAkhAYsT1F5iR3S5sCq48X8IsMuMX/ljkP7BraWAL c8/TOhfn6e+3RksOZYOf1rBSPpH48dxrfTppQIzOIritwGtKXevSnF1HBhSja60ofmDK s57YuvCWRMUHz2Epw/6pIHJw0VMbRAI87Ent8=
Received: by with SMTP id b9mr6331654wec.54.1292960307135; Tue, 21 Dec 2010 11:38:27 -0800 (PST)
Received: from [] ([]) by with ESMTPS id t11sm2118026wes.41.2010. (version=SSLv3 cipher=RC4-MD5); Tue, 21 Dec 2010 11:38:25 -0800 (PST)
Message-ID: <>
Date: Wed, 22 Dec 2010 08:38:16 +1300
From: Brian E Carpenter <>
Organization: University of Auckland
User-Agent: Thunderbird (Windows/20070728)
MIME-Version: 1.0
To: Javier Ubillos <>
References: <> <1292401029.4804.30.camel@bit> <> <1292500103.4804.1313.camel@bit> <> <1292947354.4804.8395.camel@bit>
In-Reply-To: <1292947354.4804.8395.camel@bit>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Subject: Re: [nbs] Name->Locator validation. (Was: Re: A suggestion for an "on-demand API".)
X-Mailman-Version: 2.1.9
Precedence: list
List-Id: Name based sockets discussion list <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Tue, 21 Dec 2010 19:36:32 -0000

> The basic question is, is it enough with the name->locator binding being
> OK in the beginning of the connection or must it be valid throughout the
> connection.
> Having a "last verified time-stamp" makes it very explicit that the
> name->locator binding was valid at that given point in time.
> This leaves it open for a continual polling to the nameing system if
> that is what is required by that nameing system and the application.
> It also leaves it open to the application to decide whether or not it is
> OK to have a valid name->locator binding at the beginning of the
> connection or not.

As is noted in draft-carpenter-referral-ps, these bindings
(and even nameless locators) have finite lifetimes, known at their
point of origin (from DHCP, SLAAC, DNS TTL, etc.) The problem shouldn't
be stated as timestamps or a need for polling. Quoting that draft:
"A referral that does not convey the lifetime associated with
an address is problematic." The lifetime should be carried with
the binding, and counted down locally.