var iat = ToTimestamp(DateTime.UtcNow.ToUniversalTime()) - 30000;
iat in milliseconds ??? (30000 ms)
var exp = iat + 7200;
now you add 2 hours in seconds ??? (7200 seconds)
SDK JWT Signature:
there is no c# example yet
but here is a javascript example for generating signature for SDK JWT
https://marketplace.zoom.us/docs/sdk/native-sdks/auth/
here another javascript example
and here a php example