ATC

Adaptive and Fair Hierarchical Transmission Control.

Hierarchical#

For example,

• the bandwidth is 1G/s
• there are three priorities: S, A, and B, and the bandwidth ratio is 5:3:2.

then the bandwidth of each priority is: S 500M/s, A 300M/s, B 200M/s,
even if the original speed of some priority is higher than its quota.

Problem of Hierarchical Transmission Control#

Continue with the previous example.
Sometimes S hasn’t used up its quota, while A and B have used up their quotas and want to use more. However, in Hierarchical Transmission Control, the unused quota of S can’t be used by A and B, causing a waste of bandwidth.

Adaptive#

Continue with the previous example.
ATC adapts to real-time traffic, and allocates the unused quota of a priority to others proportionally, and thus prevents the problem of hierarchical transmission control → from occurring.

Problem of Free Competition#

In free competition, some transmissions take up a lot of bandwidth because they have a competitive advantage, causing others to be too slow or even starving.

Fair#

Continue with the previous example.
ATC treats transmissions of the same priority fairly to prevent the problem of free competition → from occurring.

By the way, similar to Adaptive → , ATC adapts to real-time traffic, and allocates the unused quota of a transmission to others fairly.