Iljitsch,
I submit that as someone who has English as a first language (right?) and who has been doing this for a long time, your perception of a clear standards text isn't the same as someone who is still strugling with the language and is new to all of this.
Unless others think this is important to clarify, I am leaning to keeping the text as is. If you disagree, please suggest text.
Ok:
2.5.5 IPv6 Addresses with Embedded IPv4 Addresses
Two types of IPv6 addresses are defined that carry an IPv4 address in the low-order 32 bits of the address.
2.5.5.1 IPv4-compatible IPv6 addresses
The first, termed an "IPv4-compatible IPv6 address", was defined to assist in the IPv6 transition. The format of "IPv4-compatible IPv6 address" is:
| 80 bits | 16 | 32 bits | +--------------------------------------+--------------------------+ |0000..............................0000|0000| IPv4 address | +--------------------------------------+----+---------------------+
Note: The IPv4 address used in the "IPv4-compatible IPv6 address" must be a globally-unique IPv4 unicast address.
2.5.5.2 IPv4-mapped IPv6 addresses
A second type of IPv6 address which holds an embedded IPv4 address is also defined. This address type is used to represent the addresses of IPv4 nodes as IPv6 addresses. This type of address is termed an "IPv4-mapped IPv6 address" and has the format:
| 80 bits | 16 | 32 bits | +--------------------------------------+--------------------------+ |0000..............................0000|FFFF| IPv4 address | +--------------------------------------+----+---------------------+
2.5.5.3 IPv4-compatible IPv6 address deprecation
IPv4-compatible IPv6 addresses are now deprecated because the current IPv6 transition mechanisms no longer use them. New or updated implementations are not required to support this address type. Existing implementations and deployments may continue to use these addresses.
With these modifications, it's much less likely that someone will assume IPv4-mapped addresses are also deprecated, and the IPv4-compatible deprecation shows up in the table of contents so it's easier to find.
I like the idea of putting each type of address in a separate section, but not so about adding a separate section for the deprecation. As a compromise, how about if I add the separate section for each type and then put the deprecation text in the section on IPv4-compatible addresses? I think that will make it very clear which type of address is being deprecated.
I will send to the list a revised section with this and the other agreed changes later today.
Not unless this part constitutes the entire definition. A little recursion can work wonders now and then.
That is the "entire definition". As discussed in an earlier email, a reference is being added to point to RFC4038 that describes usage.
Good to know the art of conciseness isn't lost. :-)
:-)
Bob
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