The Citrix NetScaler architecture is built on top of x86 hardware and fully leverages recent technologies, such as multi-core processors and gigabit Ethernet ports. It can also offload compute-intensive SSL functions to any present dedicated hardware.
The core component is the integrated packet engine, which leverages kernel services and directly accesses the hardware for high-speed packet processing. This module is responsible for the major functions, such as TCP multiplexing, buffering, and acceleration. Next, the SSL engine provides decryption and encryption of the network traffic. The integrated cache can respond quickly to client requests, eliminating further content processing and additional server round-trips.
Figure A4 -NetScaler Web ADC Architecture
The compression module can compress the text into common formats, such as HTML, XML, CSS, and Microsoft Office file formats. It is based on GZIP, and works with a JavaScript-enabled Web browser to reduce bandwidth consumption and minimize latency. The application policy engine provides administrators with fine-grained control over functions, such as HTTP load balancing, TCP content switching, and URL rewriting.
Finally, the management console and command line interface (CLI) provide tools for configuration and administration. Monitoring programs that track network traffic and server load can provide real-time response metrics, alerting, and performance trend analysis.
