* Musings from ComNet
At last week’s ComNet show in Washington, D.C., consultant Jim Metzler of Ashton, Metzler & Associates joined Steve in leading a panel of experts that discussed WAN trends for 2004.
Among the enterprise challenges cited by the panel:
* Lowering total network ownership costs.
* Increasing network and application availability.
* Successfully assimilating new capabilities onto the network, such as VoIP.
In his opening remarks, Metzler offered several planning tips toward achieving these goals. First, he advised developing an enterprise-wide “WAN architecture” to guide network implementers with product and service decision-making.
WAN architecture decisions can be as basic as determining whether there will be one network for running all applications, including voice, or separate networks for different applications. More than 100 years ago, the PSTN was built to support a single application (voice). Tomorrow’s networks are meant to run many applications with differing requirements and behaviors that can impinge on one another.
This fundamental change affords you many efficiencies and new capabilities – but has potentially nontrivial performance effects if not planned and managed properly.
Once you’ve decided how many networks to run, it’s a good idea to nail down other philosophies to steer decisions. For example, which network functions do you prefer to run in customer premises equipment (CPE) and which do you prefer to outsource to a service provider? What are the business reasons?
VPNs are a good example. You can build your own VPN using CPE-based security technologies or you can use a network-based VPN service managed by your carrier.
In addition, there are different options for performing certain functions; for example, network monitoring can take place at Layer 7, 4, or 3. What’s your strategy and why?
For example, you might want to conduct dynamic monitoring at Layer 7 and combine it with traffic classification and quality of service for real-time control over application performance. For longer-term trending and capacity planning, you might want a greater depth of information at Layers 4 and 3 about network utilization.
Next time: Advice and warning from Metzler on VoIP.
