Web extra: Beyond wide-area file services

Using wide-area file services (WAFS) solutions to address talkative file-system protocols is important for network efficiency. However, employees at branch and remote offices do more than access file systems all day.

Current technology trends that aim to consolidate, centralize and control are beneficial from a budget and security standpoint. Yet workers are more distributed than ever in terms of time zones and locations, and they can strain wide-area networks.

Rich Internet-based applications also produce heavy data flows via WAN connections. Global application usage and limited bandwidth can slow work across an agency’s various office locations.

WAFS, which is a subset of wide-area data services (WDS), is geared toward optimizing all traffic between central data centers and remote locations. WDS is often referred to as WAN-optimization management or application acceleration.

Within the broader picture, there are two types of solutions: application delivery controllers (ADCs) and WAN optimization controllers (WOCs). ADCs are usually installed just in front of agency Web servers, and they are only deployed at the central data center.

ADCs address performance of Web-based applications and focus on both the network and application layers. Vendors that offer such products include F5 Networks, Cisco Systems, Nortel Networks and Radware.

WOCs -- of which WAFS solutions are one type -- are generally deployed at the central data center and at remote offices. They typically use caching, compression or acceleration -- or a combination of the three -- to increase application performance and improve WAN utilization.

Although many vendors focus on enhancing file system access, they are increasingly attempting to address all WAN traffic by including support for additional protocols, such as TCP/IP, HTTP and Domain Name System. Vendors offering WOC solutions include Packeteer, Network Appliance, Stratacache and Riverbed Technology.

Biggs, a regular Federal Computer Week contributor, is a senior engineer and freelance writer.