KEP-1645: Add spec for multi-network scenario

[aattuluri]

• Add the necessary changes to support MCS spec for multi-network scenario.

Refer to this draft for more details.

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[aattuluri]

/assign @lauralorenz

[aattuluri]

/assign aattuluri

[palnabarun]

/ok-to-test /uncc

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The committers are authorized under a signed CLA.

• :white_check_mark: aattuluri (a2fa9f44f098333f1100dd259b5b447b063d32b4, 172dd80692d73c11495b313064a1f833798a5e40, 79db429501cac719747a0ddfa52acb6c104ae208)

[bowei]

/assign @bowei

[aattuluri]

Coming back to this - do we really need this to enable multi-net MCS? It seems like this may be prematurely standardizing. In some cases MCS implementations won't need this - they will have (or have access to) enough information via other channels. Are there actually implementations that are likely to need such metadata AND which can't get it some other way (e.g. interrogating the cloud provider)?

How will such implementations learn the addresses of the ingress and egress gateways?

Right now the implementations use different mechanisms (for example Istio uses `topology.istio.io/network annotation on a control plane namespace). This spec is an attempt to standardize how a network can be determined for MCS purposes (that can have other use cases as well) before there are several different implementations of the same and then later we standardize this with a spec that would require these implementations to be rewritten or render them non-compliant.

[steeling]

Hi all, just getting up to speed on this KEP so apologies for any misunderstandings, and thanks for all the work put in so far!

Is my understanding correct that the gist of this KEP is identifying whether or not specific clusters are part of the same network, but does not solve the issue of how to route to clusters on a different network?

[aattuluri]

Hi all, just getting up to speed on this KEP so apologies for any misunderstandings, and thanks for all the work put in so far!

Is my understanding correct that the gist of this KEP is identifying whether or not specific clusters are part of the same network, but does not solve the issue of how to route to clusters on a different network?

Sorry for the delay, yes, this one is to identify if a cluster is on a different network. The routing is left to the implementation.

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PR needs rebase.

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/lifecycle rotten

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/close

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