Architecting a Hybrid Messaging Strategy with Microsoft Exchange 2013 : Designing the Solution : 7.1 Distance and Latency Considerations
   
7.1 Distance and Latency Considerations
The link between the customer’s on-premises data center and the VMware Cloud Provider facility is a significant factor in this solution architecture. Therefore, when designing a high availability and disaster recovery solution, it is important to understand factors such as link capacity, latency, and use. Typically, network latency corresponds to distance. Round-Trip Time (RTT) can vary from 0 ms to 250 ms or higher. The following table provides distances and their corresponding link latencies. Note that the values shown here are estimates and can vary significantly depending on interconnect quality, network hops, and physical infrastructure.
Table 3. 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
Verify that the design follows Microsoft Exchange Server guidelines for latency and that the required interconnect capacity requirements are known when evaluating connectivity options for the solution.