How do i get my sms messages online automatically or manually?

for example i am out of station during my holidays ....where there is no coverage of my network provider ....i shall call from an alternate number ....and receive calls to alternate number by call divert facility....but my text messages are not received/diverted.....(latter available in some network that doesn't matters)so please tell me anyone the website that provide my sms by getting it from my network provider (appreciable if its free)