Taicom Data Systems Co Ltd AWL1000G ユーザーズマニュアル

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  UBR (default): When configured as UBR (Unspecified Bit Rate), traffic is delivered with 
best efforts but with no guarantee. This allows for fluctuation in times of temporary 
increase of available bandwidth. For example, if a PVC with CBR is temporarily inactive, 
the PVC(s) with UBR will utilize that bandwidth while it is available. UBR is intended 
for applications that do not require any maximum bound on the transfer delay. 
  CBR: When a PVC is specified as a CBR (Constant Bit Rate), that PVC is guaranteed a 
certain bandwidth, characterized by the Peak Cell Rate (PCR). The CBR does not have to 
transmit with a peak cell rate, and when it does, it is only when the bandwidth specified 
by the PCR is guaranteed. 
  VBR-nrt: An PVC enabled with VBR-nrt (Variable Bit Rate - non real time) can transmit 
a cell only if the PVC has a token available. The PVC accumulates tokens at the rate of 
the Sustainable Cell Rate, and the PVC can only accumulate a maximum of the value 
specified by Maximum Burst Size tokens. 
 
When a PVC has a token available, it can transmit cells at the rate of PCR. After a cell is 
transmitted, the PVC loses the token it has accumulated. 
In the case of multiple PVCs, CBR specified PVCs will have higher priority than PVCs 
with UBR. For example, the CBR PVCs will take their bandwidth and the remaining 
bandwidth will be split among the UBR PVCs. In the case of total PVC CBR bandwidth 
exceeding ADSL upstream, the total upstream bandwidth will be shared proportionally to the 
bandwidth allocated for each CBR PVC. 
 
Peak Cell Rate: This value specifies the maximum, and in some cases guaranteed, cell rate for 
CBR and VBR-nrt. Peak Cell Rates are typically measured in Cells/Second, however, the user 
entered value is in kbps and is then converted by the firmware. 
 
Range: 0-32767 
 
Default: 0 
 
Sustainable Cell Rate: It is the sustained rate at which a PVC enabled with VBR-nrt can 
transmit ATM cells. Sustainable Cell Rate (SCR) can be considered as the true reserved 
bandwidth for a PVC. 
 
Range: 0-32767 
 
Default: 0 
 
Max Burst Size: It is the number of cells a PVC enabled with VBR-nrt can transmit 
continuously at peak cell rate (PCR). 
 
Range: 0-32767 
 
Default: 0 
 
5.2.2 DHCP Client 
DHCP Client: It is to enable or disable (default) the Router WAN as a DHCP client, where the 
ISP would be the DHCP server. DHCP Client is generally used in the following encapsulations: 
1483 Bridged IP LLC, 1483 Routed IP LLC, 1483 Bridged IP VC-MUX, 1483 Routed IP 
VC-Mux, and Classical IP over ATM. This option is for non-static (dynamic) IP addresses. 
 
Host Name: When DHCP Client is Enabled, copy the ISP recognized Host Name here. The Host 
Name can be up to 19 characters. 
 
 
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