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A token bucket scheme is used for traffic shaping. a new token is put into the bucket at every 10 micro second. assume each token pick one packet which contain 2B of data. it is observed that initial capacity of bucket is 10 Mb. the computer can transmit at full speed of 8 Mbps for _____

my question is in (C+RT) = MT

what is R? is it token arriving rate (0.1M/s) or data transmitted equivalent to token (16bits * 0.1M/s) ?

ok got it....thanks
10*2^20/(8*10^6-2*8/10*10^-6)

= 1.562
edited
Converting every parameter in terms of tokens

Token generation rate = (1/10usec)=0.1M tokens per second
Bucket capacity = 10Mb/8*2 = 0.625M tokens
Max outflow rate = 8M/16= 0.5 tokens per second
So, (C+rt/t)=M
(0.625 + 0.1*t)/t = 0.5
t=0.625/0.4=1.5625 sec

initial capacity of token bucket is given as =$10^{7}$ bits

in every 10 $\mu$ sec => 1 token is added

in 10*$10^{-6}$ sec => 1 token is added

in 1 sec =>$10^{5}$ token added

token rate=$10^{5}$ tokens/sec.

1 token is equivalent to 16 (2*8) bits of data

due to token rate  we are able to send 16*$10^{5}$ bits/sec from the host.

suppose the host transmit at maximum rate (i.e. 8mbps) for t secs

total data sent by host in t secs= 8*$10^{6}$*t

this data must be equal to the original capacity of token bucket + data transferred in 't' time due to token rate

8*$10^{6}$*t = $10^{7}$ bits + 16*$10^{5}$*t

t=1.5625s