This is an implementation of the Berkeley Algorithm in the C programming language, with the aim to distribute correctly among the clients an internal timestamp defined by a server. Raw TCP connections using sockets are used for our implementation.

Every slave sends its actual timestamp to the master and may receive a response with an adjustment to apply to its clock.

The master calculates the average of all the timestamps that it has received, including its own clock, and sends to each client the difference between the calculated average and the sent timestamp (the adjustment), if it's more than a prefixed delta-T.

packet_type = 0x00 window_id = 32 bit uint little endian

+-------------+-----------+
| packet_type | window_id |
+-------------+-----------+

packet_type = 0x01 window_id = 32 bit uint little endian clock = 64 bit little endian

+-------------+-----------+-------+
| packet_type | window_id | clock |
+-------------+-----------+-------+

packet_type = 0x69 window_id = 32 bit uint little endian s = 0x00 or 0x01 adjustment = 32 bit uint little endian

+-------------+-----------+---+------------+
| packet_type | window_id | s | adjustment |
+-------------+-----------+---+------------+

• RTT calculation: the Round Trip Time can be taken into account for the average of the timestamps
• UDP protocol: use UDP to reduce the overhead
• Master election: Fault Tolerance