HTTP-based synchronization method and apparatus

An hypertext transport protocol (HTTP) based synchronization apparatus, comprising:

• at least a memory and a processor, wherein the memory comprises program codes executable by the at least one processor to perform functions as a plurality of modules, the plurality of modules comprise:
• a transceiver module configured to obtain a first response from a source server or a cache in response to an HTTP request for obtaining a file;
• a first determining module configured to determine a first time reading when the first response is sent in a local time of the source server according to a value of a date field and a value of an age field in the first response obtained by the transceiver module;
• a second determining module configured to determine a second time reading when the first response is sent in a local time of the client according to the client time of an event related to the first response, wherein the second time reading is an arithmetic average of a client's local sending time when sending the HTTP request to the source server or the cache to obtain the file and a client's local receiving time when receiving the first response;
• and
• a synchronizing module configured to determine a first time offset between the source server time and the client time according to a difference between:
• the first time reading when the first response is sent in the local time of the source server determined by the first time determining module, and the second time reading when the first response is sent in the local time of the client determined by the second time determining module, and to set up a first synchronization relationship between the client time and the source server time according to the first time offset.