Netopia 3300-ENT Series, Руководство пользователя для прошивки

Страница: 23 / 334

WAN Configuration 2-7
Quality of Service (QoS) settings
Note:
QoS settings are not available on Ethernet-to-Ethernet WAN models.
•
Select the QoS (Quality of Ser vice) setting from the pop-up menu: UBR . CBR , or VBR .
UBR : No configuration is needed for UBR VCs. Leave the default value 0 (maximum line rate).
CBR : One parameter is required for CBR VCs. Enter the Peak Cell Rate that applies to the VC. This
value should be between 1 and the line rate. You set this value according to specifications defined by
your ser vice provider.
VBR : This class is characterized by:
• a Peak Cell Rate (PCR), which is a temporar y burst, not a sustained rate, and
• a Sustained Cell Rate (SCR),
• a Burst Tolerance (BT), specified in terms of Maximum Burst Size (MBS). The MBS is the maximum
number of cells that can be transmitted at the peak cell rate and should be less than, or equal to the
Peak Cell Rate, which should be less than, or equal to the line rate.
VBR has two sub-classes:
a. VBR non-real-time (VBR-nr t): Typical applications are non-real-time traffic, such as IP data traffic.
This class yields a fair amount of Cell Delay Variation (CDV).
b. VBR real time (VBR-r t): Typical applications are real-time traffic, such as compressed voice over IP
and video conferencing. This class transmits cells with a more tightly bounded Cell Delay Variation.
The applications follow CBR.
• Then, select a Connection Profile for the Circuit. To use the Default Profile, select Use Default Profile
for Circuit and press Return. For other options, select a profile from the Use Connection Profile
pop-up menu.
Add Circuit
Circuit Name: Circuit 2
Circuit Enabled: Yes
Circuit VPI (0-255): 0
Circuit VCI (32-65535): 32
QoS... VBR
Peak Cell Rate (0 = line rate): 0
Sustained Cell Rate: 0
Maximum Burst Size: 0
Use Connection Profile... Default Profile
Use Default Profile for Circuit
ADD Circuit NOW CANCEL
Return accepts * ESC cancels * Left/Right moves insertion point * Del deletes.