Goals & Techniques of WAN Acceleration

WAN acceleration increases the speed and efficiency of data transfers across WANs (wide area networks). Like a turbo boost for your network, it allows you to speed up your corporate WAN the way you boost your internet connection at home. Not only does WAN acceleration speed up your access but it also frees up resources to handle other tasks.

WAN acceleration uses various techniques to improve the performance of data transfer over WANs. These techniques include, data deduplication, caching, and image and file compression.

What does WAN acceleration do?

If you've ever tried to download a large file and found yourself waiting forever, you have wondered if there’s a way to accelerate your network. WAN acceleration does just that by optimizing the way data moves between your offices.

Using various techniques that we will discuss below, WAN acceleration, therefore, speeds up data transfers. The effect of this is reduced latency and bandwidth optimization, which improves network efficiency and enhances the user experience.

WAN acceleration techniques

Data deduplication

Data deduplication removes identical files from databases and data storage. It identifies and removes duplicate data before transmission. This means only unique data is sent over the WAN, significantly reducing bandwidth usage.

Picture a company where multiple remote offices need to access the same set of documents stored in a central server. Without data deduplication, every office would repeatedly download the entire file, consuming a ton of bandwidth. 

With data deduplication, the first time a document is requested, it's sent in full. Subsequent accesses would only involve transferring any changes or updates to the document, as the original data is already stored locally. This approach drastically cuts down on the data being transmitted over the WAN.

Additionally, data deduplication can work wonders with email systems. Consider an organization where employees frequently send large attachments via email. Normally, these attachments would be transmitted every single time an email is sent. 

However, with data deduplication in place, the system recognizes that the attachment has already been sent before. It then ensures that only the new, unique parts of the data are transmitted, making email communications much more efficient.

Compression

Compression reduces the size of the data that needs to travel across the network, which can speed up transmission times significantly. It's like squeezing all the unnecessary air out of a bag to make more room. 

Imagine sending a huge high-resolution image. If you compress that image, the amount of data that actually moves through the WAN link is much smaller, so it arrives faster. This works wonders for applications that rely heavily on sending large files, like email attachments or database backups.

For example, let's say you have got a team that frequently sends CAD files between branches. These files can be enormous, sometimes hundreds of megabytes. 

If you apply compression, the file size is cut down before it even hits the WAN link. The receiving end just decompresses the file back to its original size. It's the same detailed CAD drawings, but they arrive way quicker.

But it's not just about files. Compression can work with all sorts of data, including web content and software updates. Suppose your software development team is rolling out a big update to all the branches. Normally, that would be a nightmare of slow downloads and bottlenecked networks. With compression, though, the update is reduced in size, and it reaches everyone in a fraction of the time.

There are different algorithms out there for compression, and they vary in efficiency and complexity. Some are lightweight and super-fast, perfect for text-based data. Others are more heavy-duty, designed for multimedia files. 

For instance, gzip is a common compression algorithm that's particularly effective for text and HTML content. It's quick and integrates seamlessly into existing systems.

Another thing about compression is that it plays nicely with other WAN acceleration techniques. It can be combined with deduplication, where redundant data is eliminated, to maximize efficiency. 

Say the same document is being sent back and forth with minor edits. Deduplication removes the repeated data, and compression shrinks what's left. The result? Lightning-fast data transfers without the fluff.

Caching

Caching stores files in a cache, a kind of temporary storage location, so that they can be accessed more quickly. It is an effective way to reduce latency. 

By caching frequently accessed data closer to the end user, you cut down on the time it takes for data to travel back and forth. It’s like storing snacks in your desk drawer instead of running to the kitchen every time you’re hungry.

Protocol optimization

Protocol optimization makes communication between systems faster and more efficient. When you send a big file over the internet, it would normally be broken into chunks, sent one by one, and reassembled at the other end. This process can be slow, especially if there are network issues.

But with protocol optimization, you tweak this process to speed things up. One way to do this is by using TCP optimization techniques. TCP, or Transmission Control Protocol, is the backbone of most internet communication. It's reliable but can be sluggish. By optimizing TCP, you can reduce latency, improve throughput, and make the data transfer smoother.

For example, one technique is window scaling. Normally, TCP limits the size of the data window to 65,535 bytes. But with Window Scaling, you can increase this limit, allowing more data to be sent before waiting for an acknowledgment. This means fewer stops and starts, which speeds up the transfer.

Another method is selective acknowledgment, or SACK. In a standard TCP transfer, if a packet is lost, the receiver has to wait for the sender to resend all subsequent packets. This can be a real drag on performance. 

SACK allows the receiver to acknowledge individual packets that have been received correctly, so the sender only needs to resend the missing ones. This optimizes the use of bandwidth and shortens recovery time.

And then there is protocol spoofing, where a WAN accelerator tricks the client and server into thinking they're closer together than they really are. It intercepts data packets at each end of the WAN link, acknowledges them locally, and then forwards them on. This reduces the latency because the acknowledgment doesn't have to travel all the way across the WAN link.

For instance, in a Voice over IP (VoIP) setup, protocol spoofing can make calls sound clearer and reduce delay. The accelerator acknowledges the voice packets locally, so the conversation flows more naturally without those annoying pauses.

Application acceleration

Specific applications like Microsoft Office 365 or Salesforce can be optimized to reduce latency. WAN accelerators can prioritize these applications and allocate bandwidth accordingly. So, when you’re running those crucial reports, they don’t take forever.

Forward error correction (FEC)

FEC sends extra redundancy bits along with data packets to preemptively address any potential errors. It’s like having an insurance policy for your data, ensuring it arrives intact even if some bits get lost along the way.

By employing these techniques, you can significantly enhance your network performance. The goal is to make your WAN feel as fast and responsive as a local network. And with the right strategies in place, it’s totally achievable.