Congestion control in data networks

A transmitter for sending packets over a network path, wherein the transmitter comprises processing circuitry configured to:

• transmit packets over the network path;
• determine, based on a number of unacknowledged packets transmitted over the network path, whether a congestion event has occurred, wherein an unacknowledged packet is a transmitted packet for which no acknowledgement has been received;
• and
• responsive to detecting a congestion event, operating a processor to modify the number of unacknowledged packets transmitted by a multiplicative factor βi, wherein the multiplicative factor βi is proportional to a ratio of a first time value to a second time value, the first time value being indicative of a minimum time required for a packet to be transmitted over the network path and the second time value being indicative of a current time required for a packet to be transmitted over the network path.

A non-transitory computer-readable medium comprising instructions which when executed cause a processor to:

• transmit packets over the network path;
• determine, based on a number of unacknowledged packets transmitted over the network path, whether a congestion event has occurred, wherein an unacknowledged packet is a transmitted packet for which no acknowledgement has been received;
• and
• responsive to detecting a congestion event, operating a processor to modify the number of unacknowledged packets transmitted by a multiplicative factor βi, wherein the multiplicative factor βi is proportional to a ratio of a first time value to a second time value, the first time value being indicative of a minimum time required for a packet to be transmitted over the network path and the second time value being indicative of a current time required for a packet to be transmitted over the network path.