[netmod] Changing an identity base

Italo Busi <Italo.Busi@huawei.com> Fri, 27 January 2023 16:54 UTC

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From: Italo Busi <Italo.Busi@huawei.com>
To: "netmod@ietf.org" <netmod@ietf.org>
Thread-Topic: Changing an identity base
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Date: Fri, 27 Jan 2023 16:54:35 +0000
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Subject: [netmod] Changing an identity base
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According to section 11 of RFC7950, the following change is considered BC:

   o  A "base" statement may be added to an "identity" statement.

Since, as explained in section 7.18.2 of RFC7950, the derivation of identities is transitive, my understanding is that replacing a "base" statement with new  "base" statement which is derived from the previous one is also a BC change.

Considering the example below, the NEW (A) change is BC according to section 11 of RFC7950. However, NEW (B) is equivalent to NEW (A), since the new baz is derived from foo, and therefore it is also a BC change.

Is my understanding correct?

Thanks, Italo

OLD

identity foo {}

identity bar {
  base foo;
}

NEW (A)

identity foo {}

identity baz {
  base foo
}

identity bar {
  base foo;
  base baz;
}

NEW (B)

identity foo {}

identity baz {
  base foo
}

identity bar {
  base baz;
}