A method for detecting state changes between data stored in a first computing device and data requested from a second computing device, the second computing device configured to transmit a multi-part document in response to a request from the first computing device, the requested data relating to parts of the multi-part document, the method comprising: generating a first hash value of said data stored in said first computing device by generating a first pair of hash values of said data stored in said first computing device, wherein said first pair of hash values is generated by respectively applying a hash function on a uniform resource locator 'URL' and on a data attribute being requested by said first computing device; transmitting said first hash value from said first computing device to said second computing device; generating a second hash value of said data requested from said second computing device corresponding to said data stored in said first computing device by generating a second pair of hash values of data requested from said second computing device correspondingto said data stored in said first computing device, wherein said second pair of hash values is generated by respectively applying a hash function on a corresponding URL and on a corresponding data attribute stored at said second computing device; comparing said first hash value to said second hash value at said second computing device by comparing said first pair of hash values to said second pair of hash values at said second computing device, detecting a state change in the event of a difference between said hash values, and transmitting said data requested from said second computing device to said first computing device in the event said first hash value and said second hash value are different; and detecting that the hash value of said corresponding data attribute stored at said second computing device matches the hash value of a cache entry of said data attribute in said first computing device, detecting that the hash value of said corresponding URL stored at said second computing device does not match the hash value of a cache entry of said URL in said first computing device, and sending an inlined response from said second computing device to said first computing device, the inlined response comprising a Hyper Text Transfer Protocol 'HTTP' header without said corresponding data attribute, a value of the 'HTTP' header being the hash value of said corresponding data attribute stored at said second computing device. generating a first hash value of said data stored in said first computing device by generating a first pair of hash values of said data stored in said first computing device, wherein said first pair of hash values is generated by respectively applying a hash function on a uniform resource locator 'URL' and on a data attribute being requested by said first computing device; transmitting said first hash value from said first computing device to said second computing device; generating a second hash value of said data requested from said second computing device corresponding to said data stored in said first computing device by generating a second pair of hash values of data requested from said second computing device correspondingto said data stored in said first computing device, wherein said second pair of hash values is generated by respectively applying a hash function on a corresponding URL and on a corresponding data attribute stored at said second computing device; comparing said first hash value to said second hash value at said second computing device by comparing said first pair of hash values to said second pair of hash values at said second computing device, detecting a state change in the event of a difference between said hash values, and transmitting said data requested from said second computing device to said first computing device in the event said first hash value and said second hash value are different; and detecting that the hash value of said corresponding data attribute stored at said second computing device matches the hash value of a cache entry of said data attribute in said first computing device, detecting that the hash value of said corresponding URL stored at said second computing device does not match the hash value of a cache entry of said URL in said first computing device, and sending an inlined response from said second computing device to said first computing device, the inlined response comprising a Hyper Text Transfer Protocol 'HTTP' header without said corresponding data attribute, a value of the 'HTTP' header being the hash value of said corresponding data attribute stored at said second computing device.