Cisco Cisco ISA550W Integrated Security Appliance 产品宣传页
Application Note
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Ensuring Quality of Service with Cisco ISA500 Series Integrated
Security Appliances
Security Appliances
This application note explains how to use the Quality of Service (QoS) features of your Cisco ISA500
Series Integrated Security Appliance (ISA) to manage traffic and improve service on your network.
Contents
Benefits of QoS
How can you ensure that Voice over IP calls are handled without audio issues? How can you provide sufficient
bandwidth for the highest priority data transfers? You can use QoS to prioritize the types of traffic that are most
important to your business.
Typically, networks operate on a best-effort delivery basis, which means that all traffic has equal priority and an equal
chance of being delivered in a timely manner. Likewise, when congestion occurs, all traffic has an equal chance of
being dropped. You can use QoS features to select and prioritize users, applications, and services. QoS can make
network performance more predictable and bandwidth utilization more effective.
All networks can benefit from QoS for optimum efficiency. QoS is especially important for real-time streaming
multimedia applications such as voice over IP, online games, and IPTV, since these applications are delay sensitive
and often require a fixed bit rate.
In Cisco ISA500 Series Integrated Security Appliances, you can configure QoS for the WAN, the LAN, and the
wireless network. QoS is fully supported over VPN tunnels as well. You can adjust the QoS settings to achieve these
goals: