When you are operating a global business, your WAN may carry applications that are particularly sensitive to latency. For example, financial transactions, voice and video are all very latency sensitive. The fact is, the physics of distance will always affect your network performance. But utilizing the best trans-continental cable system will make a big difference in providing a low latency network to improve your performance. The people at SD-WAN-Experts understand these details completely. Your use of MPLS, VPLS or IEPL should not impact these low latency numbers. Note that the numbers below are from POP to POP. You will need to add the local loop latency to your overall equation. Remember: the greater the latency, the more dramatic the effect on your network throughput. Just 10ms on a 180ms path can
To provide you with some benchmarks to set appropriate expectations, here are some sample city pairs and their latency numbers using a low latency path:
Whether you use an MPLS network for your WAN, or a VPN over the internet, to calculate your estimated TCP throughput, you need to consider both latency and packet loss. When you have a high latency path, it is unbelievable how throughput is affected by packet loss. This is where the carrier SLA is of paramount performance: not just the “packet loss %” but how it is calculated and over what period of time. As an example with a 200ms latency: with 0.01% packet loss, theoretical throughput = 0.73Mbps. But at 0.20% PL, the throughput is 0.16Mbps, a reduction of 78%. If you use the internet, you might experience packet loss of 0.5%, which takes the throughput to 0.103Mbps, a reduction of 86%. Ouch! The consistent latency and packet loss of an MPLS network, and the resultant performance, is a major reason why the cost is justifiable for global networks.
Remember that if you are transferring files, the use of WAN Acceleration or WAN Optimization can have a dramatic effect on improving your performance. The greater the latency, the greater the performance increase from this technology.
If your interest is in the lowest possible latency network solutions, please contact SD-WAN-Experts for more information