WAN vs. WAN Optimization

By October 20, 2014How To, Networking, Strategy

Last week, I compared Sneakernet vs. WAN. And I didn’t really compare the two with any WAN optimization products—just a conservative compression ratio of around 2x, which can be had with any run-of-the-mill storage replication technology or something as simple as WinZip.

But today, I want to show the benefits of putting a nice piece of technology in between the two locations over the WAN to see how much better our data transfer becomes.

When WAN Opt Is Useful

When choosing between a person’s time or using technology, I like the tech route. But even if it’s faster, how much faster does it need to be to offset the expense, hassle, and opportunity cost of installing a WAN Opt product? The only true way to know is to buy the product, install it, and run your real-world tests; however, I’m one for asking around.

But even if it’s faster, how much faster does it need to be to offset the expense, hassle, and opportunity cost of installing a WAN Opt product?

I reached out to my friends over at Silver Peak, and they pointed me to this handy online calculator.

It turns out, WAN Optimization products aren’t always useful in some situations. If you have ample bandwidth that’s very low latency, it might not be worth it. But even marginal latency across any distance at all, or data that can be repetitive (or compresses/deduplicates well), can benefit from a WAN Opt. And if you have business RPO and RTOs, you may very well require WAN Optimization in between.

An Example

I took the example from last week: the 100mbit connection, figuring in 7ms of latency to simulate the equivalent of 50% utilization on the line with 2x compression. If you recall, the file transfer of 10TB of data moved in 10 days can translate to 370TB of data in the same time frame with a Silver-Peak appliance at both ends. Much of that efficiency is due to the way WAN Optimization works, which is to say that data doesn’t always just get compressed and streamed using multiple steams. The best WAN Opt products also don’t send duplicate and redundant data. So a transfer that would normally take a week or a day could be completed in as little as 4.5 hours or 40 minutes, respectively.

The effort to install, in reality, is not that significant. Silver-Peak appliances come in physical and virtual form, with the virtual machines being a lot quicker to spin up and a little cheaper to acquire. Just make sure you are on a relatively recent IOS code that supports WCCP on your routers, and you can quickly deploy the virtual appliance in both locations.

Additional Benefits

Aside from moving data quickly, there are other benefits, such as improved voice calls (UDP packets that arrive out of order can be reassembled in the correct order), faster response times on applications over the wire, and pretty much any type of traffic that’s TCP-IP. If it were me, I would simply compare the cost of expanding the performance of the circuit versus adding a WAN Opt product in between. For most locations in the United States, circuits are expensive and bandwidth is limited, so you’re likely better off with a Silver-Peak at both ends to save both time and cost.

If it were me, I would simply compare the cost of expanding the performance of the circuit versus adding a WAN Opt product in between.

Of course, don’t just take my word for it. Run a POC on any network that you’re having problems with, and you’ll find out soon enough if WAN Optimization is the way to go.

Photo credit via Flickr: Tom Raftery