Intel 480T, Руководство пользователя

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C H A P T E R 8 Quality of Service (QoS)
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destinations. Common elements of most browser-based
applications include the following:
• The dataflow is typically asymmetric
• Small dataflows from the browser client
• Large dataflows from the server to the browser client.
Applications based on Java
*
might create some exceptions. In
addition, Web-based applications are generally tolerant of latency,
jitter, and some packet loss. However, small packet-loss might have
a large impact on perceived performance due to the nature of TCP.
The relevant parameter for protecting browser applications is
minimum bandwidth. The relevant parameter for preventing non-
critical browser applications is maximum bandwidth.
File Server Applications
With some dependencies on the network operating system, file
serving typically poses the greatest demand on bandwidth, though
file server applications are very tolerant of latency, jitter, and some
packet loss, depending on the network operating system and the use
of TCP or UDP.
Use full-duplex links when deploying policy-based QoS. Half-
duplex operation on links can make delivery of guaranteed
minimum bandwidth impossible.
Traffic Groupings and Creating a
QoS Policy
Once a QoS profile is modified to the desired settings for bandwidth
and priority, you can assign the profile to a particular traffic
grouping. A
traffic grouping is a classification of traffic that has one
or more attributes in common.
Traffic groupings are separated into the following categories for
discussion:
• IP-based information, such as IP source/destination and TCP/
UDP port information
• Destination MAC (MAC QoS groupings)