* Field Guide to Application Delivery Systems
Tools to speed application delivery and improve application performance over WANs have been topping minds of industry watchers and enterprise IT managers, looking for ways to fix a very acute pain point.
Yet because the market is still emerging and interest in the technology seems to have reached a fever pitch, confusion around which technologies best suit certain networks and specific performance problems remains. Recently, Peter Sevcik, president of research firm NetForecast and his colleague Rebecca Wetzel released an extensive report, dubbed “Field Guide to Application Delivery Systems.” The report is available here, after registration. (It is worth noting the report was sponsored by vendors in the market, Citrix, Juniper, Packeteer, Radware and Riverbed.)
In this and the next Network Optimization newsletter, I will share some key points the industry analysts examine. For one, the report details the causes of poor performance over WANs. Among the usual suspects are long distances (which causes latency), high application turn counts (multiple interactions between client and server common in “chatty” applications) and big payloads (those due to large file transfers). Other factors that wreak havoc on performance are bandwidth limitations, network congestion and bottlenecks on overworked servers.
Couple the technology challenges with a recent uptake in business initiatives such as data center consolidation, server centralization and “application Web-ification,” the reports states, and you have an application performance nightmare on your hands.
“Poor application performance rends [end users] unproductive – therefore application performance measurement over a WAN must reflect the user’s experience,” the report reads. “The most useful measure of the [end-user] experience is task response time.”
To address this response time demand, the market seems to have evolved into two camps: an approach that requires a device in the data center alone; and an approach the puts appliances on either end of the WAN link. Dubbed Centralized Application Delivery Systems (ADS), the former approach seems to address performance mostly for Web-based applications and can be augmented with software clients in remote locations or client machines, the analysts say. Distributed ADS, according to the report, can improve performance on Web and other applications, but require customers install appliances at the location the performance upgrades are needed.
In the next Network Optimization newsletter, I will detail in which enterprise IT scenarios NetForecast says the two approaches work best.
