RFC 4282:The Network Access Identifier
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NAI length


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... NAI Length Considerations ...
... Devices handling NAIs MUST support an NAI length of at least 72 octets. Support for an NAI length of 253 octets ...
... NAIs MUST support an NAI length of at least 72 octets. Support for an NAI length of 253 octets is RECOMMENDED. However, the following implementation issues should be considered: ...


... nodes. Many devices already allow this behaviour, however. o A recommendation to support NAI length of at least 253 octets has been added, and compatibility ...



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