
222 Chapter 3—DNS for IPv6
TABLE 3-3
Field name Description
NAME Empty (the root domain)
TYPE 41 (OPT)
CLASS Sender’s UDP payload size
TTL Extended RCODE and flags
RDLEN The length of RDATA
RDATA A pair of attribute and value
The OPT r esource record for EDNS0.
The difference of the size is 56 bytes. It means each AAAA record needs an additional
28 bytes, which consist of 2 bytes of domain name (compressed),
5
2 bytes of record
type (AAAA), 2 bytes of record class (IN), 4 bytes of TTL, 2 bytes of data length (16), and 16
bytes of the data (the IPv6 address).
If we could agree on reducing the number of top level-domain servers, we would be able
to add IPv6 addresses ...