Subject: [OPSAWG] Service Assurance for Intent-based Networking Architecture and YANG modules

From: Benoit Claise <[email-masked]>
Date: Mon, 4 Nov 2019 23:45:32 +0100

Dear all,

Let me introduce these two new drafts:
     - draft-claise-opsawg-service-assurance-architecture-00
     - draft-claise-opsawg-service-assurance-yang-01

The first document describes the architecture for Service Assurance for 
Intent-based Networking (SAIN). This architecture aims at assuring that 
service instances are correctly running. As services rely on multiple 
sub-services by the underlying network devices, getting the assurance of 
a healthy service is only possible with a holistic view of network 
devices. This architecture not only helps to correlate the service 
degradation with the network root cause but also the impacted services 
impacted when a network component fails or degrades.

This second document complements the architecture by providing open 
interfaces between components, meaning YANG modules.

Feel free to read, review, and provide your feedback.

Regards, Jean & Benoit

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From: Benoit Claise <[email-masked]>
Date: Sun, 17 Nov 2019 15:56:18 +0800

Dear all,

We updated the drafts, based on the feedback received so far.
https://datatracker.ietf.org/doc/draft-claise-opsawg-service-assurance-architecture/, 
version 1
https://datatracker.ietf.org/doc/draft-claise-opsawg-service-assurance-yang/, 
version 2

Regards, Benoit

> The first document describes the architecture for Service Assurance 
> for Intent-based Networking (SAIN). This architecture aims at assuring 
> that service instances are correctly running. As services rely on 
> multiple sub-services by the underlying network devices, getting the 
> assurance of a healthy service is only possible with a holistic view 
> of network devices. This architecture not only helps to correlate the 
> service degradation with the network root cause but also the impacted 
> services impacted when a network component fails or degrades.
>
> _______________________________________________
> OPSAWG mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/opsawg

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From: Vladimir Vassilev <[email-masked]>
Date: Mon, 18 Nov 2019 03:42:00 +0000

Hi Benoit,

I read the drafts. In the context of rfc8199 the 
ietf-service-assurance.yang module seems to be designed as Network 
Service YANG Module. However the concept of a service is general enough 
to cross into the domain of Network Element YANG Modules. There is a 
similar need for service management on the network element level. 
systemd for example used as default service manager on Debian systems 
among others aims to provide uniform interface to management of services 
on network elements and its data model can be mapped to a general YANG 
module with augmentation specific to the network element context.

Do you think the idea of extending the scope with a very abstract module 
(with top level container /ietf-services:services) to both domains of 
Network Service and Network Element modules is relevant for this draft?

Vladimir

On 17/11/2019 09.31, Benoit Claise wrote:
>> for Intent-based Networking (SAIN). This architecture aims at 
>> assuring that service instances are correctly running. As services 
>> rely on multiple sub-services by the underlying network devices, 
>> getting the assurance of a healthy service is only possible with a 
>> holistic view of network devices. This architecture not only helps to 
>> correlate the service degradation with the network root cause but 
>> also the impacted services impacted when a network component fails or 
>> degrades.
>>

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From: Benoit Claise <[email-masked]>
Date: Wed, 27 Nov 2019 14:46:59 +0100

Hi Vladimir,

Thanks for your feedback.
> Service YANG Module.
Yes, but not exclusively
> However the concept of a service is general enough
Yes.

> Network Service and Network Element modules is relevant for this draft?
The question stems from the "service" definition, which might have 
multiple facets.
You can configure a service and this service is actually a service for 
someone else:
      - the IGP for L3VPN
     - a device for an IGP
     - a DHCP for a device
     - An IPFIX service on a device
     - etc.
The assurance graph was created to be flexible and open, regardless of 
where the subservices are
Some subservices might be located on devices (device health, systemd, 
etc.), some in the network (IS-IS health) and some others linked to the 
orchestrator (network service health)

This is the reason why we created the generic top container as

	module: ietf-service-assurance

... applicable to both Network Service and Network Element.

If this is not clear from the text, feel free to let us know.

Regards, Jean & Benoit