Instruction manual

Chapter 1: Introduction to the NetScaler 9000 Series
1-16 NetScaler 9000 Series Installation and Configuration Guide - Volume 1
NSICG60_JAN05
conventional approach of distributing connections among these systems. Load
balancing decisions are based on a variety of policies including round robin,
least connections, weighted least bandwidth, weighted least packets,
minimum response time and hashing (based on URL, domain source IP or
destination IP).
As both TCP and UDP protocols are supported, all HTTP, HTTPS, UDP,
DNS, FTP, NNTP, and general firewall traffic can be load balanced. In
addition, The NetScaler 9000 system can maintain session persistence based
on source IP, cookie, server, group, or SSL session. The NetScaler 9000
system also allows users to apply custom Extended Content Verification
(ECV) to servers, caches, firewalls and other infrastructure devices to ensure
that these systems are functioning properly and providing the right content to
users. The NetScaler 9000 system can also perform other health-monitoring
checks via ping, TCP, or HTTP URL.
1.5.4.2 Content Switching
Using a powerful policy engine, the NetScaler 9000 system switches
individual content requests to the server best able to respond. Site rules can be
configured based on URL and any combination of HTTP headers. This allows
switching decisions to be made based on user and device characteristics such
as who the user is, what type of agent they are using, and the content they
request.
1.5.4.3 Cache Redirection
Cache redirection manages the flow of traffic to a reverse proxy, transparent,
or forward proxy cache farm. It inspects all requests, identifies non-cacheable
requests and then sends those requests directly to the origin servers over
persistent connections. By intelligently, redirecting non-cacheable requests
back to the origin web servers, the NetScaler 9000 system frees cache
resources and increases cache hit rates while reducing overall bandwidth
consumption and response delays for these HTTP requests.
1.5.4.4 Global Server Load Balancing
The NetScaler 9000 system extends its traffic management capabilities to
include distributed Internet sites and global enterprises. Whether installations
are spread across multiple network locations or multiple clusters in a single
location, the NetScaler 9000 system maintains availability and distributes