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8520-R1 4-Port Wireless N Gateway
59
4.5.2 WAN
– ATM Settings
The page is for ATM PVC QoS parameters setting. The DSL device support 4 QoS mode
–
UBR,CBR,rt-VBR,nrt-VBR.
Fields in this page:
Field
Description
VPI
Virtual Path Identifier. This is read-only field and is selected on the
Select
column in
the Current ATM VC Table.
VCI
Virtual Channel Identifier. This is read-only field and is selected on the
Select
column in the Current ATM VC Table. The VCI, together with VPI, is used to identify
the next destination of a cell as it passes through to the ATM switch.
QoS
Quality of Server, a characteristic of data transmission that measures how accurately
and how quickly a message or data is transferred from a source host to a destination
host over a network. The four QoS options are:
UBR (Unspecified Bit Rate): When UBR is selected, the SCR and
MBS fields are disabled.
CBR (Constant Bit Rate): When CBR is selected, the SCR and MBS
fields are disabled.
nrt-VBR (non-real-time Variable Bit Rate): When nrt-VBR is
selected, the SCR and MBS fields are enabled.
rt-VBR (real-time Variable Bit Rate): When rt-VBR is selected, the
SCR and MBS fields are enabled.
PCR
Peak Cell Rate, measured in cells/sec., is the cell rate which the source may never
exceed.
CDVT
Cell Delay Variation Time. The Cell Delay Variation is a term used in ATM
(Asynchronous Transfer Mode) to describe the time difference that is acceptable
between cells being presented at the receiving host. Available only when VBR QoS
is chosen.
SCR
Sustained Cell Rate, measured in cells/sec., is the average cell rate over the