Architecting a Hybrid Database Strategy with Microsoft SQL Server : Designing the Solution : 6.1 Distance and Latency Considerations
   
6.1 Distance and Latency Considerations
The data center link between the customer’s on-premises and VMware Cloud Provider facility is a significant factor in this solution architecture. Therefore, it is important to have an understanding of factors such as link capacity, latency, and utilization when designing a high availability and disaster recovery solution. Typically, network latency corresponds to distance, and Round-Trip Time (RTT) can vary from
0 ms to 250 ms or higher. The following table provides distances and their corresponding link latencies. The values shown here are estimates and can vary significantly depending on interconnect quality, network hops, and physical backbone.
Table 4. Distance and Estimated Link Latency
Approximate Distance
One-Way Latency (ms)
Round-Trip Latency (ms)
50 km
0.25
0.5
500 km
2.5
5
1,000 km
5
10
5,000 km
25
50
10,000 km
50
100
20,000 km
100
200
22,500 km
125
250