HP-UX IPQoS A.01.00 Administrator's Guide (October 2005)

Introduction
Planning for HP-UX IPQoS Deployment
Chapter 1 29
Planning for HP-UX IPQoS Deployment
Before you begin using HP-UX IPQoS, you must plan your implementation. The following
sections discuss a high-level planning overview, general planning considerations including
network-wide considerations, and HP-UX host specific planning considerations.
Overview
You need to begin by understanding the current traffic on your network. As part of your
network traffic analysis, determine where the traffic bottlenecks are, when they happen, and
what are the largest contributors. There is a general rule that assumes you will identify the
“knee of the curve”. In other words, there is often an inflection point where the steepness of
the curve changes significantly. Before the knee, incremental traffic leads to incremental
delays, whereas after the knee of the curve, incremental traffic leads to significant increased
delays.
Once you have identified where the worst bottlenecks are, define policies and filters that give
priority to essential traffic, and limit the rest. The more detail you gather, the more
specifically you can define the filters and policies.
In general, use a common sense approach to managing your network traffic. Analyze your
network thoroughly before making changes. Start with a simple filter and policy, so that
analysis can be done easily. Take measurements and determine if you are getting intended
results without unintended consequences. If so, you can continue to expand the filters and
policies to achieve your traffic management goals.
NOTE A detailed network-wide QoS planning strategy discussion is beyond the scope
of this guide.
General Planning Considerations
Implementing HP-UX IPQoS as part of your overall QoS strategy is an iterative process. As
part of your preparation and to determine how HP-UX IPQoS fits into your larger QoS
(DS-aware) network, you must take several planning steps, including the following:
• Analyze your organization’s needs and goals. Break them down into manageable sizes.
Prioritize them. Define the results needed to happen to meet specific goals.