Re: [MBONED] Adoption Call: draft-jholland-mboned-ambi-04

"Holland, Jake" <jholland@akamai.com> Mon, 09 March 2020 02:29 UTC

Return-Path: <jholland@akamai.com>
X-Original-To: mboned@ietfa.amsl.com
Delivered-To: mboned@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 77CA83A100A for <mboned@ietfa.amsl.com>; Sun, 8 Mar 2020 19:29:35 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.1
X-Spam-Level:
X-Spam-Status: No, score=-2.1 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=akamai.com
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 C_ti5dSdK0jl for <mboned@ietfa.amsl.com>; Sun, 8 Mar 2020 19:29:25 -0700 (PDT)
Received: from mx0a-00190b01.pphosted.com (mx0a-00190b01.pphosted.com [IPv6:2620:100:9001:583::1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id CC2853A0F80 for <mboned@ietf.org>; Sun, 8 Mar 2020 19:28:30 -0700 (PDT)
Received: from pps.filterd (m0122333.ppops.net [127.0.0.1]) by mx0a-00190b01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 0292Ru6d004436; Mon, 9 Mar 2020 02:28:22 GMT
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=akamai.com; h=from : to : subject : date : message-id : references : in-reply-to : content-type : content-id : content-transfer-encoding : mime-version; s=jan2016.eng; bh=h5vUrbohstlvsypw+N2w+jEPZ00x3tWB4Vto/v0NdkA=; b=hJ38eaHsad9JhCTHHczbl8b7HrKC20Pwp3U7cCoE0PaypsAuyIKH6RD0gY+aIsDh0Ast JVpLKPX2UrIxvMGavzcOLexVmH4hPtLuJvLvlHNl1EU+AT915RgbfSdmtMQ4ep08oCSJ YYdeGd3zgUb2TkD2liWKSl+BeNftENiR/WwjuAYAbdmctp3sgrqamPkVaprANOhNGNmH uCiv2MP1mLjHZ5izcB4f68F5hrT52+IoqBllgfKqRToc8JT5AeOFg3vB44vX+GdLwb1u rmr6hsb9uZBDUNOq3ooPPCbX1ZkmsHVV9pMJlzE2XtErL29ZN1iyIlLvNB2RgTk1dB6i /A==
Received: from prod-mail-ppoint6 (prod-mail-ppoint6.akamai.com [184.51.33.61] (may be forged)) by mx0a-00190b01.pphosted.com with ESMTP id 2ym3re5mx6-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 09 Mar 2020 02:28:21 +0000
Received: from pps.filterd (prod-mail-ppoint6.akamai.com [127.0.0.1]) by prod-mail-ppoint6.akamai.com (8.16.0.27/8.16.0.27) with SMTP id 0292HbVV012607; Sun, 8 Mar 2020 22:28:20 -0400
Received: from email.msg.corp.akamai.com ([172.27.123.31]) by prod-mail-ppoint6.akamai.com with ESMTP id 2ym7ty1a3x-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT); Sun, 08 Mar 2020 22:28:20 -0400
Received: from usma1ex-dag1mb6.msg.corp.akamai.com (172.27.123.65) by usma1ex-dag1mb2.msg.corp.akamai.com (172.27.123.102) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Sun, 8 Mar 2020 22:28:19 -0400
Received: from usma1ex-dag1mb6.msg.corp.akamai.com ([172.27.123.65]) by usma1ex-dag1mb6.msg.corp.akamai.com ([172.27.123.65]) with mapi id 15.00.1497.006; Sun, 8 Mar 2020 22:28:19 -0400
From: "Holland, Jake" <jholland@akamai.com>
To: "Manfredi (US), Albert E" <albert.e.manfredi@boeing.com>, "mboned@ietf.org" <mboned@ietf.org>
Thread-Topic: [MBONED] Adoption Call: draft-jholland-mboned-ambi-04
Thread-Index: AQHV9ONfxdoQUPcKvkCP2NLAxrn/mqg/dvuAgABCKAD//5+VAA==
Date: Mon, 9 Mar 2020 02:28:19 +0000
Message-ID: <F86DCB72-A098-4B6F-985A-A725D5B85F39@akamai.com>
References: <CABFReBqK8d=wYwDWzs64yFk_dB5U=tCOK90Tu3BffFAaxNf4OA@mail.gmail.com> <CAHANBtLDjzDbP=z-jjXEcJnY00dOLGV7_FC3_oQwDRa+QVYNUw@mail.gmail.com> <ad61bee9-ff3f-0ee3-ac28-11c9507e13d6@concordia.ca> <c1e2f1036a114153b981a676aafa788b@boeing.com>
In-Reply-To: <c1e2f1036a114153b981a676aafa788b@boeing.com>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
user-agent: Microsoft-MacOutlook/10.22.0.200209
x-ms-exchange-messagesentrepresentingtype: 1
x-ms-exchange-transport-fromentityheader: Hosted
x-originating-ip: [172.19.112.140]
Content-Type: text/plain; charset="utf-8"
Content-ID: <9129B0041C8A0D438D4A27BE379CDB86@akamai.com>
Content-Transfer-Encoding: base64
MIME-Version: 1.0
X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.572 definitions=2020-03-08_09:2020-03-06, 2020-03-08 signatures=0
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-2002050000 definitions=main-2003090015
X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.572 definitions=2020-03-08_09:2020-03-06, 2020-03-08 signatures=0
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 suspectscore=0 clxscore=1011 adultscore=0 spamscore=0 priorityscore=1501 malwarescore=0 phishscore=0 impostorscore=0 lowpriorityscore=0 bulkscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2003090016
Archived-At: <https://mailarchive.ietf.org/arch/msg/mboned/V0ceLY1EooEqRYwqlNiH5-UOIRo>
Subject: Re: [MBONED] Adoption Call: draft-jholland-mboned-ambi-04
X-BeenThere: mboned@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Mail List for the Mboned Working Group <mboned.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/mboned>, <mailto:mboned-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/mboned/>
List-Post: <mailto:mboned@ietf.org>
List-Help: <mailto:mboned-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/mboned>, <mailto:mboned-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 09 Mar 2020 02:29:51 -0000

Hi Bert,

Thanks for taking a look and for asking questions!

On 3/8/20, 6:15 PM, "Manfredi (US), Albert E" <albert.e.manfredi@boeing.com> wrote:
>    If the manifests, in AMBI's current incarnation, are unicast, then why bother with the multicast stream at all? Why not unicast the data in authenticated or encrypted packets, the same way as the manifests have to be unicast?

For scale.  If you're sending full-sized (~1500-byte) multicast packets, the
authenticated manifest stream is only 1-3% of the data stream, so even with
unicast manifests you get a substantial benefit.

We do also hope eventually to publish a way to send the manifests over multicast
with a one-way asymmetric signature scheme, but that's not as far along yet, and
we think we can get a big efficiency gain even with the simpler unicast manifest
stream.

I went over this a bit in Singapore, if you want a slightly longer explanation:
https://www.youtube.com/watch?v=ttGJyd5is2w&t=1h07m45s

I maybe should also add a paragraph or 2 to the draft if this isn't clear from the
text, thanks for raising it.

>    Conversely, for authenticated or encrypted multicast traffic, is it not simpler to use a symmetric key stream cipher, with wide enough packet sequence numbers to permit the new secret key to be sent to all multicast group members, out of band, at a relatively low rate? If you can show that the sequence number never repeats, with a given secret key, you're done. Let's say, update the secret key daily, using any low data rate key exchange protocol.

The problem with this is that the receivers do not trust each other, for instance
in a video broadcast scenario.

So if all the receivers share a secret, there's a problem if any of those receivers
are able to inject traffic into the data stream, and that's not as hard as one might
wish if you're using AMT for ingest, or if the network itself injects traffic for its
end users (evidently this has happened before in some flavors of ad-hijacking, but
could also be used for things like packets of death that could compromise receivers).

This is addressed in one of the references from the intro section of AMBI describing
the motivation, but maybe I should import the description of that issue for a better
in-line explanation if it isn't clear.  But this section of TESLA gives an explanation:
https://tools.ietf.org/html/rfc4082#section-1

Best regards,
Jake