Справочное Руководство для Netopia r3100-u

The Committed Information Rate is a tool your Frame Relay ser vice provider uses to manage your PVCs. The 
CIR measures the average amount of normal priority data your Frame Relay network will attempt to deliver in a 
given time inter val.

The Committed Burst specifies the maximum amount of data that your Frame Relay ser vice provider agrees to 
transfer under normal conditions over the time inter val T

. The value for T

 is calculated with the formula:

T

c

= B

c

/CIR

Data in excess of B

c

 may be discarded if the network becomes congested.

The Excess Burst specifies the maximum amount of data that your Frame Relay ser vice provider will attempt to 
deliver over the time inter val T

.

In the absence of congestion, data will be transmitted at a rate equal to or less than the excess burst. That rate 
is calculated according to the following formula:

(1+ B

e

/ B

c

) * CIR = excess rate

Your Frame Relay ser vice provider will attempt to deliver data containing excess bursts, but reser ves the right 
to discard excess bursts in order to manage congestion within the network.

where:

Access rate

Ma

x. b

urs

t r

at

e

CIR

data may be

discarded

send data

as received

discard all data

> B  + B

e

c

B  + B

e

c

c

B

o

T

T  + T

o

c