Edimax Technology AR-7265WnB User Manual

Page 34

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26

Parameter

Description

VCI

VCI is the label given to an ATM VC to identify it and

determine its destination. The VCI is a 16-bit number that

is included in the header of an ATM cell. The valid range

for the VCI is 32 to 65535. Enter the VCI assigned by the

ISP.

ATM QoS

CBR (Constant Bit Rate) – This class is used for

emulating circuit switching. The cell rate is constant with

time. Select CBR to specify fixed (always on) bandwidth

for voice or data traffic.

UBR (Unspecified Bit Rate) – Select UBR for applications

that are non-time sensitive, such as e-mail.

rtVBR (real time Variable Bit Rate) – This class is similar

to nrtVBR but is designed for applications that are

sensitive to cell-delay variation. Examples for real-time

VBR are voice with speech activity detection (SAD) and

interactive compressed video.

nrtVBR (non-real time Variable Bit Rate) – This class

allows users to send traffic at a rate that varies with time

depending on the availability of user information.

Statistical multiplexing is provided to make optimum use

of network resources. Multimedia e-mail is an example of

nrtVBR.

PCR

Divide the DSL line rate (bps) by 424 (the size of an ATM

cell) to find the PCR (Peak Cell Rate). This is the

maximum rate at which the sender can send cells.

SCR

SCR (Sustain Cell Rate) is the average rate, as

measured over a long interval, in the order of the

connection lifetime.

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