Dealing with Latency Between the United States and India

My company is in the process of setting up an office in India. Because of the distance between this office and our California headquarters, and because of the lack of local support we'll have in the remote office, we're trying to maintain as much of the new office's infrastructure as possible at our headquarters. Our telecom-services provider has told us that in addition to the expense of a dedicated frame-relay circuit between California and India, we can expect a high round-trip latency—on the order of 220ms. This restriction will make it difficult to extend our existing Citrix MetaFrame infrastructure, and I'm concerned that it might also be a problem for video and Voice over IP (VoIP). Do you have any comments or suggestions?

Wow, where do I start? First, let me say that your telecom provider is doing you a disservice by telling you to expect a 220ms round trip. The provider might be able to engineer a ping from its US Point of Presence (POP) to its Indian POP and record a 220ms latency (ask the provider about the packet size it uses in its tests), but you have practically no chance of seeing that low of a round-trip latency between your local and remote routers—especially considering the other traffic that will be traveling across that circuit. You're more likely to see a latency of anywhere from 265ms to 309ms, depending on the remote office's location (India is a big country), the Indian telecom provider, the path taken from the United States to India and, most important, circuit availability.

Part of the reason for the high latency is that no direct underwater fiber cables connect the United States and India. More than likely, you'll be connecting through Japan, the Philippines, and Singapore (and possibly a few other locations) before you even reach the coast of India. So, in short, you have gravity working against you.

Also keep in mind that the telecom provider that the remote office uses can make a big difference with regard to performance and reliability. Many times, the choice of providers isn't something over which you have any control. However, find out as much as you can about the remote provider's capabilities so that you know what to expect.

As far as expense is concerned, I recommend against using frame relay. I know this idea might be contrary to what you experience in the United States, but frame relay to India is often more expensive than a point-to-point circuit. Frame relay is also slower than point-to-point.

Fortunately the news isn't all bad. The newer versions of MetaFrame shouldn't have any difficulty dealing with a 309ms round-trip latency; you typically won't begin to hit issues with voice and video until your round-trip latency starts to exceed 315ms. As long as packet loss doesn't become a concern (and it shouldn't on a point-to-point circuit), neither your Citrix infrastructure nor your voice and video services should have any trouble traveling between the United States and India.