Consider a Token Bucket algorithm with a bucket size of B and a token refill rate of R tokens per second. If the network traffic arrives at a burst of N packets, each of size S bytes, and the maximum allowed transmission rate is M bits per second, under what condition will the bucket overflow?

If the burst of traffic arrives faster than tokens can be replenished, causing the accumulated tokens to exceed B.

If the total size of the burst (N * S) exceeds the bucket size B.

If the rate of token refill R is less than the average arrival rate of tokens required for the traffic.

If the network is saturated, meaning M is less than the combined size and arrival rate of the burst.

A Leaky Bucket algorithm is implemented with a fixed output rate of C. If a large burst of packets arrives, what is the primary behavior of the algorithm regarding the output stream?

The output rate will remain constant at C, potentially causing a delay for arriving packets.

The output rate will increase proportionally to the burst size.

The algorithm will drop all packets exceeding the capacity of the bucket.

The output rate will fluctuate based on the instantaneous arrival rate of packets.

Which of the following best describes the difference in how Token Bucket and Leaky Bucket handle traffic bursts?

Token Bucket permits bursts up to its bucket size, while Leaky Bucket smooths all traffic to a constant rate.

Leaky Bucket allows bursts up to its capacity, while Token Bucket enforces a constant output rate.

Both algorithms smooth traffic to a constant rate, but Token Bucket has a larger buffer.

Token Bucket drops excess traffic, while Leaky Bucket allows controlled bursts.

Consider a network device using a Token Bucket algorithm to police traffic. If the bucket size is 1000 tokens and the refill rate is 10 tokens per millisecond. A flow attempts to send 5000 tokens in 100 milliseconds. What will be the outcome?

2000 tokens will be accepted, and the rest will be dropped.

All 5000 tokens will be accepted.

Only 1000 tokens will be accepted.

5000 tokens will be accepted if the maximum transmission rate is not exceeded.

Which statement accurately characterizes the primary goal of a Leaky Bucket implementation in Quality of Service (QoS)?

To shape network traffic into a more predictable and consistent flow.

To allow for maximum possible data transmission, even if it causes congestion.

To prioritize certain types of traffic over others.

To measure the actual bandwidth utilization of a network link.

In a Token Bucket implementation, if the bucket size B is very large and the refill rate R is high, how does it behave?

It approaches a completely unpoliced traffic flow.

It becomes similar to a strict Leaky Bucket.

It allows for very large bursts but still enforces an average rate.

It essentially becomes an inefficient packet dropper.

What is a key advantage of the Token Bucket algorithm over the Leaky Bucket algorithm in certain scenarios?

It allows for controlled bursts of traffic, providing better throughput for bursty applications.

It guarantees a constant output rate, reducing jitter.

It is simpler to implement and requires less memory.

It is more effective at preventing network congestion.

Consider a scenario where a network needs to guarantee a minimum bandwidth for a critical application while allowing other applications to use remaining bandwidth. Which algorithm is fundamentally more suited for this type of traffic differentiation or prioritization?

Neither is directly suited; priority queuing mechanisms are needed.

If a Leaky Bucket has a capacity of C bytes and packets arrive at an average rate higher than C, what happens to packets that arrive when the bucket is full?

They are transmitted immediately.

They are temporarily stored until space is available.

They are re-queued for later transmission.

What is the typical relationship between bucket size (B) and refill rate (R) in a Token Bucket algorithm when trying to accommodate 'average rate' traffic with occasional small bursts?

B should be sufficient to hold tokens for the expected burst duration, and R should match the average rate.

B should be small, and R should be high.

B should be large, and R should be small.

B and R should be proportional to the average traffic rate.

Consider two traffic flows: Flow A sends data at a constant rate of 5 Mbps. Flow B sends data in bursts of 10 Mbps for 1 second, followed by 0.5 seconds of silence. If both flows are policed by a Token Bucket with a bucket size of 5 Megabits and a refill rate of 5 Mbps, how will they be treated?

Flow A will be limited to 5 Mbps; Flow B will be limited to 5 Mbps and will drop packets during bursts.

Flow A will be limited to 5 Mbps; Flow B will be limited to 5 Mbps average and may experience drops.

Flow A will pass unimpeded; Flow B will be limited to 5 Mbps average but can burst up to 10 Mbps.

Flow A will be limited to 5 Mbps; Flow B will be limited to 5 Mbps average, and after 1 second, it will have stored enough tokens to transmit at 10 Mbps for the next 0.5 seconds.

Which of the following is a potential drawback of using a Leaky Bucket algorithm for real-time applications like VoIP?

It may drop packets during periods of high network utilization, which is detrimental to real-time streams.

It can introduce excessive jitter due to variable output rates.

It allows for unpredictable bursts that can overload downstream devices.

It enforces a strict constant delay, which is not ideal for real-time audio.

If a Token Bucket algorithm is used to enforce a committed information rate (CIR) of R and a peak information rate (PIR) up to a certain burst size B, what is the primary role of B?

To allow for temporary deviations from the CIR up to a specified burst magnitude.

To limit the average transmission rate.

To smooth out traffic variations.

To discard packets that exceed the PIR.

How does the behavior of a Leaky Bucket differ from a simple fixed-rate shaper when the input traffic rate is consistently below the shaper's rate?

Their behavior will be identical; both will transmit traffic at the input rate.

The Leaky Bucket will introduce more delay.

The Leaky Bucket will drop more packets.

The Leaky Bucket will smooth traffic, while the simple shaper will not.

Token Bucket vs Leaky Bucket

Token Bucket vs Leaky Bucket - Test Paper