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As well as to all the existing implementations: PlaintextAuthenticationContext, SslAuthenticationContext and SaslAuthenticationContext.

That will return the ListenerName used by the connection. For example, with the following configuration:

listener.security.protocol.map=CLIENT:SASL_PLAINTEXT,REPLICATION:PLAINTEXT,INTERNAL_SASL:SASL_PLAINTEXT
advertised.listeners=CLIENT://cluster1.foo.com:9092,REPLICATION://broker1.replication.local:9093,INTERNAL_SASL://broker1.local:9094
listeners=CLIENT://192.1.1.8:9092,REPLICATION://10.1.1.5:9093,INTERNAL_SASL://10.1.1.5:9094

For a client connecting to:

• 192.1.1.8:9092, it will return "CLIENT"
• 10.1.1.5:9093, it will return "REPLICATION"
• 10.1.1.5:9094, it will return "INTERNAL_SASL"

Compatibility, Deprecation, and Migration Plan

No compatilibty, deprecation, migration plan required.

Rejected Alternatives

If there are alternative ways of accomplishing the same thing, what were they? The purpose of this section is to motivate why the design is the way it is and not some other way.

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