Intermediary (potential
Eavesdropper) is a
protocol entity that sits between the
initiator and the
recipient and is necessary for the
initiator and
recipient to perform
telecommunications.
Unlike an eavesdropper, an intermediary is an entity that is part of the telecommunications architecture and therefore at least tacitly authorized.
For example, a SIP RFC 3261 proxy is an intermediary in the SIP architecture.
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