Transaction Signature (TSIG) Keys

On Compute Cloud@Customer, you can create, add, and delete TSIG keys.

A DNS transaction signature (TSIG) is a network protocol defined in RFC 2845. The main purpose of the TSIG is to allow DNS to authenticate updates to a DNS database, so that malicious users can't change name resolution records to point to a bogus IP address instead of (for example) the IP address of a bank. TSIG uses one-way hashing and shared secret keys to provide a secure means to authenticate the endpoints of a connection for processing (or responding to) DNS update requests.

The TSIG protocol uses timestamps to prevent replay of recorded responses. Therefore, DNS servers and TSIG clients need accurate clocks to provide the timestamps. Several extensions to the basic TSIG protocol have been made to extend the types of cryptography and hashing methods that are supported by TSIG.

To use TSIG for a DNS zone, add TSIG keys to the DNS zone. The TSIG key must be base64 encoded.

Creating a TSIG Key

On Compute Cloud@Customer, you can create TSIG keys to ensure that DNS packets originate from an authorized sender by using shared secret keys and one-way hashing to add a cryptographic signature to the DNS packets.

To add a TSIG key to an existing list of TSIG keys, simply create another key with a unique TSIG key name and a new algorithm or a new key value. To modify fields in an existing TSIG key, use the update command.

A TSIG key is a separate object from a DNS zone. You can have a SECONDARY DNS zone reference a TSIG key as part of its ExternalMaster definition. But creating a new key doesn't do anything for a PRIMARY zone.

Deleting a TSIG Key

On Compute Cloud@Customer, you can delete a TSIG key.