802.11n
Wireless
ADSL
2/2+
Router
ADN
‐
4102
28
3.4.1.3 ATM
Click
ATM
in the left pane and the page shown in the following figure appears. On this page, you can
configure the parameters of the ATM, including QoS, PCR, CDVT, SCR and MBS.
The following table describes the parameters:
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 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.
SCR
Sustained Cell Rate, measured in cells/sec., is the average cell rate over the
duration of the connection.
MBS
Maximum Burst Size, a traffic parameter that specifies the maximum number of
cells that can be transmitted at the peak cell rate.
CDVT
Cell delay variation tolerance (CDVT) is the amount of delay permitted between
ATM cells (in microseconds).
