RFC 3588:Diameter Base Protocol
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IP version


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... bit width MUST be valid for the IP version and the IP number MUST NOT have bits ...
... NOT have bits set beyond the mask. For a match to occur, the same IP version must be present in the packet that was used in describing the IP address ...
... the IP address. To test for a particular IP version, the bits part can be set to zero ...


... Hinden, R. and S. Deering, "IP Version 6 Addressing Architecture", RFC 2373(-> 3513(-> 4291draft)), July 1998. ...



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