The Importance of Keeping Up With WAN Optimization Techniques

To understand the different techniques used by appliances offering WAN optimization, it's important to first define exactly what exactly a 'WAN' is. WAN stands for 'wide area network' and refers to any network that covers a very large geographic area. By contrast, a LAN, or local area network, refers to networks that provide internal communication in a home or small office. The internet as a whole can be defined as a WAN and is obviously a public network, while an example of a private WAN could be a corporation with offices in San Francisco, San Jose, Austin, Boston, and New York. Each individual office would have a LAN set up internally, but could also use DSL or MPLS connections to form a WAN to share information between offices.

There are a number of performance-related issues that typically occur with WANs, which has led to the development of various WAN optimization techniques. These issues can include redundant transmissions, 'chatty' protocols, and packet delivery issues. Some of the common techniques used to achieve WAN optimization include: Bandwidth Management; Caching; and Protocol Optimization. Multiple vendors offer WAN optimization appliances that use a number of these techniques to process the IP traffic traveling between the sites over the company's WAN. Not every solution uses the same techniques, thus the benefits can vary, which is important to understand when researching a vendor or supplier.

Bandwidth Management allows applications to have set limits and minimums with regard to how much bandwidth they use. For example, this technique would allow you to put a limit on the amount of bandwidth an especially avaricious application can use. Conversely, bandwidth management can ensure that less-used applications always have a guaranteed amount of bandwidth allocated to them.

Caching allows several copies of important files, especially larger ones, to be stored in multiple locations. This prevents users from having to download files as large as 20MB or 100MB across a WAN connection every time they need to view or make edits to it. Additionally, whenever modifications are made to one of these cached files, the network doesn't have to transmit the entire updated file to every one of its multiple locations. One the portions of the file that have been edited are sent.

Communication protocols for digital computer network communication have features intended to ensure reliable interchange of data over an imperfect communication channel. It is basically a way of following certain rules so that a system works properly. Protocol optimization restricts the amount of electronic chit-chat that occurs between sites when communication protocols send their necessary back and forth confirmation messages.

The implementation of these various techniques by using WAN optimization appliances has been said to reduce the usage of bandwidth by as much as 50-95% between offices communicating over the WAN. For many companies this means thousands of dollars of savings, particularly when costly solutions like multiple MPLS networks are being to ensure network reliability. For others, the value of WAN optimization is that global collaboration allows the company to undertake tasks that it previously couldn't. Regardless of the benefit or the need, understanding the latest in WAN Optimization techniques can have a substantial benefit on the performance of a modern corporation.

Charles Hughes is author of this article on WAN Optimization.

When Should You Add More Bandwidth To Your Business Network (eg WAN)?

Many businesses ask this question. It's common ..... so don't feel alone.

Is there a general rule of thumb, a percentage of bandwidth usage, that is an indicator that it is time to lease more bandwidth?

The true answer here is, "It depends".

Of course you need to know how many users you have ..... and what they're using the network for (e.g. CAD, Multi-media applications, sharing large data files, medical imagery, etc.). That's a factor in your ultimate decision obviously. As is what is the operation, are users on one side and servers on the other, are servers and users on both sides, how many points? Plus .... are either of those categories (number of users, applications) going to grow in the near future.

If growth of users and/or applications is in the distant future ..... you have more room to plan and maybe go with a gradual solution in the interim. In this case you may be able to go with a bonded T1 or burstable DS3 bandwidth rather than a full DS3 or OC3 bandwidth.

Before you can make a real decision on increasing your bandwidth though (thus increasing your expenses) the first step is to log/record your bandwidth usage patterns for a specific period of time - I'd say at least a month (30 day period). This will create a decent benchmark on where you stand in regards to your bandwidth needs.

Ignore occasional spikes -- spikes will happen, this is a reality of networking. However if you have sustained spikes lasting for several minutes at a time and this occurs at least once every day that is a hint of a larger problem.

(If that happened I'd note the time of day such spiking occurs, then correlate the times if they match up to any specific task the company is doing during that time period each day).

However, as a general rule ..... look at the bandwidth usage throughout the day. If the average usage is at 50% then start to talk about increasing the bandwidth. If it's at 70%, you will start seeing major trouble, don't just talk about increasing bandwidth then, DO IT.

If you want to be a bit more lenient rather than conservative on your benchmarks ..... get excited about increasing bandwidth when you consistently see usage at 75% bandwidth, when it hits 85% there is no debate, no talking ..... just order more bandwidth.

But, remember to base your decision on the average usage ..... not the spikes that may occur during the day. Again, spikes will happen no matter what your bandwidth is.

Here's another tip (or two) .......

Much of the time bandwidth is not the problem, but the amount of clutter and the lack of optimization at the machine level.

So ..... on every computer on the network do the following:

First, delete any temporary files (even temporary system files) in the c:\windows\temp directory and in their profile under local settings.

Second, get rid of any unused applications.

Third, ensure that the swap file is optimized.

Fourth, Stick more memory in the system if possible.

Last, Defrag the hard drive!

Following the above you should be able to reclaim some speed. If speed is your main issue (it isn't always).

Also .... if you get your files of a network server don't forget to optimize that as well. But the first rule we tell users is do not work off server copies if you can help it.

Now, if after going through all of the above you still decide you do need more bandwidth ..... you can get free assistance to find the right solution (at the best price too) at DS3-Bandwidth.com.

Michael is the owner of FreedomFire Communications....including DS3-Bandwidth.com and Business-VoIP-Solution.com. Michael also authors Broadband Nation where you're always welcome to drop in and catch up on the latest BroadBand news, tips, insights, and ramblings for the masses.