ZyXEL Communications ZyWall USG20-VPN, Руководство пользователя

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USG20(W)-VPN Series User’s Guide
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BWM (Bandwidth Management)
26.1 Overview
Bandwidth management provides a convenient way to manage the use of various services on the
network. It manages general protocols (for example, HTTP and FTP) and applies traffic prioritization
to enhance the performance of delay-sensitive applications like voice and video.
26.1.1 What You Can Do in this Chapter
Use the BWM screens (see Section 26.2 on page 405 ) to control bandwidth for services passing
through the USG, and to identify the conditions that define the bandwidth control.
26.1.2 What You Need to Know
When you allow a service, you can restrict the bandwidth it uses. It controls TCP and UDP traffic.
Use policy routes to manage other types of traffic (like ICMP).
Note: Bandwidth management in policy routes has priority over TCP and UDP traffic
policies.
If you want to use a service, make sure both the security policy allow the service’s packets to go
through the USG.
Note: The USG checks security policies before it checks bandwidth management rules for
traffic going through the USG.
Bandwidth management examines every TCP and UDP connection passing through the USG. Then,
you can specify, by port, whether or not the USG continues to route the connection.
BWM Type
The USG supports three types of bandwidth management: Shared , Per user and Per-Source-IP .
The Shared BWM type is selected by default in a bandwidth management rule. All matched taffic
shares the bandwidth configured in the rule.
If the BWM type is set to Per user in a rule, each user that matches the rule can use up to the
configured bandwidth by his/her own.
Select the Per-Source-IP type when you want to set the maximum bandwidth for traffic from an
individual source IP address.
In the following example, you configure a Per user bandwidth management rule for radius-users to
limit outgoing traffic to 300 kbs. Then all radius-users ( A , B and C ) can send 300 kbps of traffic.