IP hard pipe, defined in IETF RFC 7625, is an IP network-based technology that provides bandwidth guarantee and low delay for services. Conventional IP networks allow bandwidth reuse, but do not allow key services to exclusively use fixed bandwidth. IP hard pipe strictly isolates soft and hard pipes by reserving hardware so that soft and hard pipes do not affect each other. Even if traffic bursts occur in the soft pipe, they cannot preempt hard pipe bandwidth. IP hard pipe reserves bandwidth and ensures low delay for services, and therefore can be used to carry leased line services of high-value customers.