Posted by: Eric Siegel
It's the end of my writing quarter, and I'm putting the
finishing touches on a paper for management about WAN performance optimization
(also called WAN Optimization Controller [WOC]) technologies.
That reminded me to make a note that WAN performance
optimization isn't always the best
solution, although I do think it's great! (See, for example, my previous blog
entries "Final
Catalyst WAN Performance Optimization Notes" and "Be
a Hero! Cut costs to Zero!"; there are others.) (And, by the way,
Catalyst is a great place to meet your colleagues! So let's put in an advert
for them: Go To Catalyst!)
Here are some alternatives to WAN performance optimization
that should always be considered:
- Application redesign or reselection: In some cases, it's better to replace a few poorly-designed applications instead of trying to alter the WAN characteristics. Backup and file transfer or distribution applications that don't remove long duplicate data strings ("deduplication") or that handle transmission errors or congestion inefficiently are prime examples. The Burton Group report “Designing Applications for the WAN” was written to assist programmers in designing applications properly for operation over the WAN, thereby avoiding the need for optimization.
- Application remoting: Often called "terminal server" or "Citrix," this solution is best for applications that are tightly-intertwined with some remote service; for example, an application in a remote office that makes frequent calls on a database in the enterprise's central server location. Application remoting can also save money on licensing fees and has other advantages. Application Remoting data flows will probably require network QoS.
- System tuning: In some cases (e.g., inability to use all of the bandwidth in a high-latency path), simply tuning existing software or upgrading to more recent version (e.g., shifting to Microsoft Windows Vista from Windows/XP) can produce massive results at minimal cost.
- WAN service modification: For some situations, the need for more bandwidth or better network delay or error characteristics is unavoidable or is the most cost-effective solution. In some cases, technology changes (e.g., to satellite from terrestrial links) are also involved. Renegotiation of carrier contracts and changing carriers are also options.
See the Burton Group report "WAN
Performance Optimization Quick Start" to learn about WAN performance
optimization, and wait for my new Management Initiative document "WAN
Performance Optimization" if you have to discuss things with your
management. (As always, if you desperately need it now, and you're a Burton
Group client, send me an email and I'll give you a pre-publication copy.)
