On Wed, 8 May 2019 07:56:33 +0000 Lars Prehn <lprehn@mpi-inf.mpg.de> wrote:

do you NTP sync your AS boundary routers? If so, what are incentives for doing so? Are there incentives, e.g. security considerations, not to do it?

In addition to what others have mentioned, if these systems are to perform route origin validation (ROV), an accurate notion of time would be desirable. From section 6 in IETF RFC 7115 / BCP 185 - Origin Validation Operation Based on the Resource Public Key Infrastructure (RPKI): As a router must evaluate certificates and ROAs that are time dependent, routers' clocks MUST be correct to a tolerance of approximately an hour. John