Re: [tcpm] How to reuse the tcp model in the BMP model - asking for suggestions

["Scharf, Michael" <[e-mail]>]

Hi Camilo,

There are existing examples for YANG modules that model application-specific configuration for TCP connections, such as:

  *   draft-ietf-idr-bgp-model
  *   draft-ietf-netconf-tcp-client-server

I would assume that BMP could be modeled like that.

Note that the model for TCP-AO authentication has changed in draft-ietf-tcpm-yang-tcp-07 because of last call comments, i.e., some model aspects can still be subject to change.

Michael

From: Camilo Cardona <[e-mail]>
Sent: Friday, June 17, 2022 4:37 PM
To: Scharf, Michael <[e-mail]>; [e-mail]; [e-mail]
Cc: [e-mail]; [e-mail]
Subject: Re: How to reuse the tcp model in the BMP model - asking for suggestions


Hello Michael,



First of all, thanks for considering our questions and letting us know about this new version.



Please keep in mind that the BMP model draft is in very early stages, not even a WG draft yet, it might change in the future. So, we apologise if we cannot give you exact requirements.



Having said that, it will feasible that the model will need to include multiple TCP configurations. Defining the connection might be specific to the application, but BMP requires other  features like authentication, MSS, keepalives which seem general enough. What we wanted was to leverage other model for this, if existing.



Thus, I guess the most general question we can make is , How is the recommended way of reusing the tcp model?



Thanks,

Camilo Cardona


From: "Scharf, Michael" <[e-mail]<mailto:[e-mail]>>
Date: Friday, 17 June 2022 at 04:26
To: Camilo Cardona <[e-mail]<mailto:[e-mail]>>, "[e-mail]<mailto:[e-mail]>" <[e-mail]<mailto:[e-mail]>>, "[e-mail]<mailto:[e-mail]>" <[e-mail]<mailto:[e-mail]>>
Cc: "[e-mail]<mailto:[e-mail]>" <[e-mail]<mailto:[e-mail]>>, "[e-mail]<mailto:[e-mail]>" <[e-mail]<mailto:[e-mail]>>
Subject: RE: How to reuse the tcp model in the BMP model - asking for suggestions

Hi Camilo,

We have looked into the question of groupings when preparing version -07, which tries to address other last call reviews (see https://datatracker.ietf.org/doc/html/draft-ietf-tcpm-yang-tcp-07 or https://www.ietf.org/rfcdiff?url2=draft-ietf-tcpm-yang-tcp-07). Yet, we decided not to introduce groupings in -07.

We would like to first better understand the actual use case in your model. Why would the BMP yang model indeed use exactly the same definitions of “common”, and “statistics” sections of ietf-tcpm?

The counters in statistics typically apply the whole TCP stack, not to an application. Why would your model not use application-specific events instead?

Also, the exact status of a TCP connection as seen by the TCP stack will typically not matter to the application. Note that this part of the model also has changed in -07 because of other review comments. Would your model indeed want to include e.g. the internal state of a TCP connection?

Note that it is possible that a follow-up version -08 will be required due to other reviews, i.e., we could look at this question in a version -08 again.

Thanks

Michael


From: Camilo Cardona <[e-mail]<mailto:[e-mail]>>
Sent: Tuesday, May 3, 2022 5:40 PM
To: [e-mail]<mailto:[e-mail]>; [e-mail]<mailto:[e-mail]>
Cc: [e-mail]<mailto:[e-mail]>; [e-mail]<mailto:[e-mail]>
Subject: How to reuse the tcp model in the BMP model - asking for suggestions

Hello draft-ietf-tcpm-yang-tcp authors,

We are analysing how to leverage the tcpm model for managing tcp connectivity in the BMP yang model (draft-cptb-grow-bmp-yang-02).

In general, how do you suggest other models reuse ietf-tcpm? Most of tcpm model is defined directly in containers, not as groups, and we are finding hard to take the pieces that we need.

Let us shortly gointo details.

Regarding the 4-tuple connection, in BMP, we would like to have a “default” case in which the configured device connects to another using ip/port (i.e. active case),  but also to provide the option of expecting the  tcp connection over a local ip/port (i.e. passive case). We might need our own container for this.

However, we would like to integrate the “common”, and “statistics” sections of ietf-tcpm, but, they are containers, so we really do not know what to do besides recreating it.

Do you have any suggestions?

Thanks,
draft-cptb-grow-bmp-yang authors