RFC 3514:The Security Flag in the IPv4 Header
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element


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... bit is set to 0, the packet has no evil intent. Hosts, network elements, etc., SHOULD assume that the packet is harmless, and SHOULD NOT take any defensive measures. (We note that this part of the spec is already implemented by many common ...


... This document defines the behavior of security elements for the 0x0 and 0x1 values of this bit. Behavior for other values of the bit ...



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