Hi Anthony, The difference you noted is intentional. See this prior message for background: http://www.ietf.org/mail-archive/web/6lowpan/current/msg02379.html
-- Jonathan Hui On Nov 2, 2010, at 9:35 AM, Anthony Baire wrote: > Hi all, > > > the 6lowpan-hc draft (Section 3.3.2) describes how to derive an interface ID > from a 802.15.4 short address: >> A short IEEE 802.15.4 address is 16 bits in length. Short addresses >> are mapped into the restricted space of IEEE EUI-64 addresses by >> setting the middle 16 bits to 0xfffe, the bottom 16 bits to the short >> address, and all other bits to zero. As a result, an IID generated >> from a short address has the form: >> >> 0000:00ff:fe00:XXXX >> >> where XXXX carries the short address. The universal/local bit is >> zero to indicate local scope. >> > > > But this is not identical to the method described in RFC 4944 (Section 6) > >> All 802.15.4 devices have an IEEE EUI-64 address, but 16-bit short >> addresses (Section 3 and Section 12) are also possible. In these >> cases, a "pseudo 48-bit address" is formed as follows. First, the >> left-most 32 bits are formed by concatenating 16 zero bits to the 16- >> bit PAN ID (alternatively, if no PAN ID is known, 16 zero bits may be >> used). This produces a 32-bit field as follows: >> >> 16_bit_PAN:16_zero_bits >> >> Then, these 32 bits are concatenated with the 16-bit short address. >> This produces a 48-bit address as follows: >> >> 32_bits_as_specified_previously:16_bit_short_address >> >> The interface identifier is formed from this 48-bit address as per >> the "IPv6 over Ethernet" specification [RFC2464]. However, in the >> resultant interface identifier, the "Universal/Local" (U/L) bit SHALL >> be set to zero in keeping with the fact that this is not a globally >> unique value. > > According to RFC 4944, the resulting interface id should look like: > > YYYY:00ff:fe00:XXXX (where YYYY is derived from the PAN ID) > > > The PAN ID is not included in 6lowpan-hc. Is this an omission ? > > > Best Regards > > Anthony Baire > > > _______________________________________________ > 6lowpan mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/6lowpan
_______________________________________________ 6lowpan mailing list [email protected] https://www.ietf.org/mailman/listinfo/6lowpan
