Function Time

Create a rule to assign or check SigTime.

Remarks

This rule assigns SigTime to be same as current timestamp, but may increment if it duplicates the previous value.

This rule rejects an Interest on any of these conditions:

• SigTime is absent.
• SigTime differs from current timestamp by more than maxClockOffset milliseconds.
• SigTime value is less than or equal to a previous value.

This check logic differs from NDN Packet Format v0.3 specification (as of 2020-September) in that maxClockOffset is checked on every Interest rather than only the "initial" Interest. It is the same behavior as ndn-cxx v0.7.1 implementation. This logic offers better consistency as it has less dependency on internal state of the SignedInterestPolicy. However, persistently sending more than 1000 signed Interests per second would eventually push SigTime out of maxClockOffset range and cause rejections.