User`s manual

MP-202 Telephone Adapter 62 Document #: LTRT-50605
User's Manual
3. From the drop-down list select the device for which to shape traffic. The drop-down list
includes all your interfaces as well as category options (e.g., All LAN Devices, All
WAN Devices) and VPNs such as PPoE, PPTP and L2TP (if defined). Select, for
example, the option 'WAN Ethernet' and click ‘OK’; the ’Edit Device Traffic Shaping’
screen opens (refer to the figure).
Figure 8-2: QoS - Edit Device Traffic Shaping
4. Configure the following fields:
Table 8-1: Edit Device Traffic Shaping - Parameter Descriptions
Parameter Description
Tx Bandwidth This parameter limits the gateway’s bandwidth transmission rate. The purpose is
to limit the bandwidth of the WAN device to that of the weakest outbound link, for
instance, the DSL speed provided by the ISP. This forces the gateway to be the
network bottleneck, where sophisticated QoS prioritization can be performed. If
the device’s bandwidth is not limited correctly, the bottleneck will be in an
unknown router or modem on the network path, rendering the gateway QoS
useless.
Rx Bandwidth In the same manner, this parameter limits the gateway’s bandwidth reception
rate to that of the DSL modem.
TCP Serialization You can enable TCP Serialization in its combo box, either for active voice calls
only or for all traffic. The screen will refresh, adding a ’Maximum Delay’ field
(refer to the figure). This function allows you to define the maximal allowed
transmission time frame (in milliseconds) of a single packet. Any packet that
requires a longer time to be transmitted, will be fragmented to smaller sections.
This avoids transmission of large, bursty packets that may cause delay or jitter
for real-time traffic such as VoIP.