TKEY (transaction key) is a record type of the Domain Name System (DNS). TKEY resource records (RRs) can be used in a number of different modes to establish shared keys between a DNS resolver and name server.
| Field | Description | Length (octets) |
|---|---|---|
| NAME | Key name, which must be unique on client and server | Variable |
| TYPE | TKEY (249) | 2 |
| CLASS | Ignored, should be ANY (255) | 2 |
| TTL | Ignored, should be 0 | 4 |
| RDLENGTH | Length of RDATA field | 2 |
| RDATA | Variable-length structure containing the timestamp, algorithm, mode, hash data and error | Variable, as per RDLENGTH |