Signed API V2 For external use we offer an API that requires each request to be sent with a "signature" created using the request content and a timestamp. This makes each signature useful for a short time only and prevents possible replay attacks. Signed API V2 Base URL: https://nrsdb.uk/api/nrsdb/v2 Signature Send the following HTTP Headers X-NRSDB-Signature X-NRSDB-Timestamp X-NRSDB-Key Endpoints ESRs https://nrsdb.uk/api/nrsdb/v2/esrs?age=3