NTT's All-Photonics Network (APN) has achieved ultra-low latency over metro-area distances, demonstrating the potential for higher-performance data center interconnected.
NTT published results of APN connections between its data centers near London and in Northern Virginia, achieving round-trip delays of less than 1 millisecond. These tests also showed significantly reduced jitter.
Two data centers, HH2 in Hemel Hempstead and LON1 in Dagenham, in the United Kingdom, and VA1 and VA3 in Ashburn, in the United States, were connected using NEC APN equipment to measure round-trip delays and delay jitter between the two data centers.
As a result of the demonstration experiment, both data centers were connected with delay of less than 1 millisecond and delay jitter of less than 1 microsecond at 400Gbps. In the U.K., the delay2 between data centers at the same distance as this demonstration exceeds 2 milliseconds.
NTT notes that conventional networks with general Layer 2 switch experience delay jitter of several microseconds to tens of microseconds. A major cloud service provider specified that the conditions under which data centers can be treated as the same data center are 2 milliseconds3, which is significantly lower than the delay expected for general cloud applications.
