In the above question leaky bucket is used.
So, consider the following diagram :
In the network of Computer A, the bandwidth acceptable is 6Mbps.
A is supposed to transmit a file of 19.5 MB which equals to 156 Mb
So, 6 Mb can be sent in 1 sec
156 Mb can be sent in 156 / 6 = 26 secs
Now the problem is router network can accept the packet at a rate of 4Mbps
So, in 1 sec, the router network can accept a data of 4 Mb
In 26 secs, the router network can accept a data of 26 * 4 = 104 Mb
So, the time at which A transmits a 156 Mb data, during that time the router network can accept 104 Mb of data.
Now what will happen to the remaining 156 – 104 = 52 Mb of data ?
So, the queue in the bucket has to take the responsibility for that else the remaining 52 Mb data will get discarded.
Hence, the capacity of the queue in the bucket should be 52 Mb.
Ans : 52 Mb.