IANA
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Error messages not currently defined by IANA:
o Unallocated Error messages (Types 5-99 inclusive and 102-126
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All informational messages with types not explicitly assigned by
IANA, currently:
o Unallocated Informational messages (Types 154-199 inclusive and
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... review the set of messages affected in case new message types are
assigned by IANA.
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All informational messages with types not explicitly assigned by
IANA, currently:
o Types 154-199 inclusive and 202-254 inclusive.
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... Kempf, J., "Instructions for Seamoby and Experimental Mobility Protocol IANA Allocations", RFC 4065exp, July 2005. ...
... A large number of ICMPv6 Type values are currently unused. These
values have not had a specific function registered with IANA. This
section describes how to treat messages that attempt to use these
Type values ...