[irs-discuss] IRS problem statement and NETCONF/YANG
Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de> Tue, 31 July 2012 14:49 UTC
Return-Path: <j.schoenwaelder@jacobs-university.de>
X-Original-To: irs-discuss@ietfa.amsl.com
Delivered-To: irs-discuss@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 604D021F8670 for <irs-discuss@ietfa.amsl.com>; Tue, 31 Jul 2012 07:49:39 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -103.198
X-Spam-Level:
X-Spam-Status: No, score=-103.198 tagged_above=-999 required=5 tests=[AWL=0.051, BAYES_00=-2.599, HELO_EQ_DE=0.35, RCVD_IN_DNSWL_LOW=-1, USER_IN_WHITELIST=-100]
Received: from mail.ietf.org ([12.22.58.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id EJO-7+wosCDx for <irs-discuss@ietfa.amsl.com>; Tue, 31 Jul 2012 07:49:38 -0700 (PDT)
Received: from hermes.jacobs-university.de (hermes.jacobs-university.de [212.201.44.23]) by ietfa.amsl.com (Postfix) with ESMTP id 2CA7D21F8665 for <irs-discuss@ietf.org>; Tue, 31 Jul 2012 07:49:38 -0700 (PDT)
Received: from localhost (demetrius4.jacobs-university.de [212.201.44.49]) by hermes.jacobs-university.de (Postfix) with ESMTP id 1B3B820BD9; Tue, 31 Jul 2012 16:49:33 +0200 (CEST)
X-Virus-Scanned: amavisd-new at jacobs-university.de
Received: from hermes.jacobs-university.de ([212.201.44.23]) by localhost (demetrius4.jacobs-university.de [212.201.44.32]) (amavisd-new, port 10024) with ESMTP id tuHPHfT0qhQx; Tue, 31 Jul 2012 16:49:32 +0200 (CEST)
Received: from elstar.local (elstar.jacobs.jacobs-university.de [10.50.231.133]) by hermes.jacobs-university.de (Postfix) with ESMTP id 69C7D20BCD; Tue, 31 Jul 2012 16:49:32 +0200 (CEST)
Received: by elstar.local (Postfix, from userid 501) id CD3DD20FCCE7; Tue, 31 Jul 2012 16:49:30 +0200 (CEST)
Date: Tue, 31 Jul 2012 16:49:30 +0200
From: Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>
To: irs-discuss@ietf.org
Message-ID: <20120731144930.GA78451@elstar.local>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Disposition: inline
User-Agent: Mutt/1.5.21 (2010-09-15)
Subject: [irs-discuss] IRS problem statement and NETCONF/YANG
X-BeenThere: irs-discuss@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
Reply-To: Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>
List-Id: "Interface to The Internet Routing System \(IRS\)" <irs-discuss.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/irs-discuss>, <mailto:irs-discuss-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/irs-discuss>
List-Post: <mailto:irs-discuss@ietf.org>
List-Help: <mailto:irs-discuss-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/irs-discuss>, <mailto:irs-discuss-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 31 Jul 2012 14:49:39 -0000
Hi, reading through the problem statement posted at http://lucidvision.com/draft-atlas-irs-problem-statement-00.txt I noticed a number of statements concerning NETCONF and YANG that probably need to be corrected. For more background where NETCONF and YANG is, you may want to consult the tutorial slides posted at http://cnds.eecs.jacobs-university.de/slides/2012-ietf-84-netconf-yang.pdf and consult the documents referenced in the slides. Some more detailed comments: : Finally, the IETF's Network Configuration (or NetConf) protocol has : made many strides at overcoming most of the limitations around : configuration that were just described. However, the lack of : standard data models have hampered the adoption of NetConf. The NETMOD working group has been chartered to work on common core data models and currently has core data models for the configuration of network interfaces, ip interfaces and a core routing configuration data model in WG last call: http://tools.ietf.org/html/draft-ietf-netmod-routing-cfg-04 http://tools.ietf.org/html/draft-ietf-netmod-ip-cfg-05 http://tools.ietf.org/html/draft-ietf-netmod-interfaces-cfg-05 : While NetConf has solved many of the deficiencies present in SNMP in : terms of configuration, it still does not satisfy a number of : requirements needed to manage today's routing information. First, : the lack of standard data models have hampered the adoption of : NetConf; a significant amount of per-vendor customization is still : needed. The transport mechanisms that are currently defined (e.g., : SOAP/BEEP) for NetConf are not those commonly used by modern : applications (e.g., ReST or JSON). The default to implement transport for NETCONF is SSH. There is another transport over TLS. The BEEP and SOAP transports are on their way to be declared historic. That said, there is work underway to define a JSON / REST API to YANG modelled NETCONF data stores. http://tools.ietf.org/html/draft-bierman-netconf-yang-api-00 http://tools.ietf.org/html/draft-lhotka-yang-json-00 : NetConf primarily facilitates configuration rather than reading of : state or handling asynchronous events. Not sure what primarily facilitates means but NETCONF does support all three functions. NETCONF allows read access to all existing SNMP instrumentation of devices. : NetConf matches up to the key needed aspects as follows : : Multiple Simultaneous Asynchronous Operations: Not Possible The NETCONF protocol tags RPC invocations with a message-id that is echoed back in RPC replies, allowing asynchronous operations. NETCONF also provides global and partial locks to properly deal concurrent operations received via multiple channels. : Configuration Not Re-Processed: Not Possible I simply do not understand the definition of this aspect. You document says: : Configuration Not Re-Processed: When an IRS operation is processed, : it does not require that any of the configuration be processed. : I.e., the desired behavior is orthogonal to the static : configuration. A clarficiation is needed what you mean with this. Anyway, NETCONF distinguishes between different configuration data stores. If you want to distinguish between changes that affect only the current behaviour but not say the next startup behaviour (i.e. the changes do not persist), then this is already supported by NETCONF. Perhaps your concern is that making a change requires to reprocess the whole configuration? In that case, this is clearly not required anywhere by the NETCONF protocol specification. In fact, the edit-config operation allows to send detailed configuration change sets to a NETCONF server. : Duplex: Not Possible - strict pull model. NETCONF does have support for event notifications that are pushed by the device. The initiation of the session is client to server for the existing transports - but this is mostly a property of the transports. Some vendors use non-standard extensions for the SSH transport to support device initiated sessions. : High-Throughput: Unlikely - Can depend on configuration size Well, this is ill defined in the first place. Your definition is: : High-Throughput: At a minimum, the IRS Agent and associated router : should be able to handle hundreds of simple operations per second. So what is a "simple operation"? I am rather optimistic that it is possible to do some "simple operation" in NETCONF at the requested speed. To be useful, you really need to be more precise. : Responsive: Unlikely - Can depend on configuration size Again, this is under specified. Your definition is: : Responsive: It should be possible to complete simple operations : within a sub-second time-scale. I am sure NETCONF servers easily respond within a sub-second time-scale. We have several implementors here at the IETF, I am sure they can provide more concrete information about the efficiency aspects. : Multi-Channel: Not Possible NETCONF allows to use multiple SSH or TLS sessions (hence multiple TCP sessions) and it provides the needed coordination primitives. In addition, the SSH transport can be used to run multiple SSH channels multiplexed over a single TCP session. /js -- Juergen Schoenwaelder Jacobs University Bremen gGmbH Phone: +49 421 200 3587 Campus Ring 1, 28759 Bremen, Germany Fax: +49 421 200 3103 <http://www.jacobs-university.de/>
- [irs-discuss] IRS problem statement and NETCONF/Y… Juergen Schoenwaelder
- Re: [irs-discuss] IRS problem statement and NETCO… Alia Atlas
- Re: [irs-discuss] IRS problem statement and NETCO… Juergen Schoenwaelder