This morning, we received a call from a company that does software development in China, with their base of operations in the Boston area. Today, they use a VPN over the internet and the performance is poor. “We need latency of less than 100ms” I was told.
I explained that the distance is so great, that the speed of light takes more than 100ms to reach around the world. It is simply impossible to have a connection of 100ms with such a great distance with any known technology today. Even if you had an uninterupted dedicated fiber! The further the distance, the greater the latency.
But since MPLS, depending on the CoS provides >99.9% packet delivery, the latency is not as noticeable and your application performance is much better than when using a VPN over the Internet. But you can’t fool with photonic physics. Light, in a vacuum travels at 186 miles per millisecond. But in a low-loss network with switches, routers and fiber splices, that number is closer to 75 -90 miles per millisecond, as the crow flies. But remember: latency numbers are typically round-trip numbers, so you need to double the number.