iPECS SBG-1000 User Manual

iPECS SBG-1000 User Manual (DATA Features)
WAN interface gateway, the gateway may have to communicate with the ISP using a modem with
a bandwidth of 2Mbps. This typical configuration makes the modem, having no QoS module, the
bottleneck.
Instead of sending traffic as fast as it is received, iPECS SBG-1000’s QoS algorithms perform
traffic shaping, limiting the bandwidth of the gateway, thus artificially forcing it to become the
bottleneck. A traffic shaper is essentially a regulated queue that accepts uneven and/or bursty
flows of packets and transmits them in a steady, predictable stream so that the network is not
overwhelmed with traffic. While Traffic Priority allows basic prioritization of packets, Traffic Shaping
provides more sophisticated definitions, such as:
• Bandwidth limit for each device
• Bandwidth limit for classes of rules
• Prioritization policy
• TCP serialization on a device
Additionally, you can define QoS traffic shaping rules for a default device. These rules will be used
on a device that has no definitions of its own. This enables the definition of QoS rules on Default
WAN, for example, and their maintenance even if the PPP or bridge device over the WAN is
removed.
5.3.4.1 Shaping the Traffic of a Device
To shape the traffic of a device, perform the following:
1. Click ‘Traffic Shaping’ under the QoS tab in the ‘Services’ screen. The ‘Traffic Shaping’
screen appears.
Figure 5.58 Traffic Shaping
2. Click the ‘New Entry’ link. The ‘Add Device Traffic Shaping’ screen appears (see
Figure 5.59).
3. Select the device for which you would like to shape the traffic. The drop-down menu
includes all your gateway’s devices, and you can select either a specific device for which to
shape the traffic, or ‘All Devices’ to add a traffic class to all devices. In this example, select
the WAN Ethernet option.
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