Re: [babel] Example configuration

[Mahesh Jethanandani <[e-mail]>]

> On Aug 7, 2019, at 11:55 AM, STARK, BARBARA H <[e-mail]> wrote:
> 
>  
> 
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> What I had in mind for the updates to the information model are step 5. If the operator needs to update link-quality, or flip on split-horizon, or set a RTT estimate value, or specify whether they want to use unicast instead of multicast, or any combination thereof for a particular interface, they would create a new babel-link-properties object and associate that with the interface.
> 
> Can we agree on the changes to the information model I suggested yesterday?
>  
> <bhs> Let me see if I understand... Does it have to be a “new” babel-link-properties instance, or can it be one that exists?
>  
> That is, if we had an object called babel-link-properties 
>      object {
>           string                rw babel-link-properties-name;
>           [string               rw babel-interface-metric-algorithm;]
>           [boolean               rw babel-interface-split-horizon;]
>           [boolean               rw babel-interface-rtt;]
>           [boolean               rw babel-interface-unicast;]
>       } babel-hmac-keys-obj babel-link-properties;

[mj] with the corrections marked in red.

>  
> Where the implementation may create some set of initial entries that its developers have decided to e.g. name “wired”, “wireless”, “tunnel” (but some other implementation may give a different name to the same group of parameter values). link-properties-name must be unique (and not empty or NULL), but also no 2 instances are allowed to have the same set of values for the latter 4 parameters. Once an instance is created it cannot be modified. If it is referenced from an interface or was created by the implementation, it cannot be deleted. This makes instances created by the implementation immutable.
> This object can be written (new instances created with different combinations of values and a different name, like “unicast-wired”).
> An interface will have a reference to one of these instances, to identify the set of link-properties it uses. It’s allowed to modify which set of link-properties is used/referenced by an interface.
>  
> Is that right? And did you say you wanted it under interface or under the base? I think it would make sense under base. Juliusz, I think this approach (if it’s what Mahesh meant) would provide the benefits of allowing users to use more meaningful names for groups of link properties, allow use of names that babeld has already popularized among its users while allowing other implementations to use different names (names aren’t standardized), and isn’t very complicated. It does make it harder if the user wants to just change one of the link properties and not others (they might have to create a new instance). But it makes it easier for the user who wants to change from one grouping of properties to another.

[mj] Yes, that is what the intention of the change was. Note, I did want instances of babel-link-properties to exist under the base (babel-informtion-obj). In babel-interface-obj we only reference one of those instances:

object {
          ….
          [babel-link-properties   rw babel-link-properties<0..*>;]

} babel-information-obj;

object {
         [reference                      rw  babel-link-properties;]
          …..
} babel-interface-obj;

> Barbara

Mahesh Jethanandani
[e-mail]