meta-flow: Document nw_proto limitation for IPv6 later frags.
@@ -4101,6 +4101,15 @@ r r c c c.
opcodes greater than 255 are treated as 0; this works adequately
because in practice ARP and RARP only use opcodes 1 through 4.
</p>
+
+ <p>
+ In the case of fragmented traffic, a difference exists in the way
+ the field acts for IPv4 and IPv6 later fragments. For IPv6 fragments
+ with nonzero offset, <code>nw_proto</code> is set to the IPv6 protocol
+ type for fragments (44).
+ Conversely, for IPv4 later fragments, the field is set based on the
+ protocol type present in the header.
+ </p>
</field>
<field id="MFF_IP_TTL" title="IPv4/v6 TTL/Hop Limit">
