RFC 3588:Diameter Base Protocol
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UDP


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... transport RADIUS runs over UDP, and does not define retransmission behavior; as a result, reliability ...


... SCTP [SCTP] protocol is ; assumed. UDP MUST NOT be used when ; the aaa-protocol field is set to ...
... With the TCP, UDP and SCTP protocols, optional ports ...
... conjunction with either tcpflags or TCP/UDP port specifications. ...



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