Write a simple Windows command line script (batch)

We need a simple windos batch script that does the following: 1) Make a GET-request to a webserver 2) Open a modem connection with rasdial 3) Make a POST-request to a webserver 4) Disconnect model connection 5) Append line with date and time to a log file GET and POST requests: You may use curl, a very powerful command line tool, for GET and POST requests ([login to view URL]) The POST request has a query string, which must be signed with a sha1 hash. To compute the hash, you may use [login to view URL] or a similar tool. Example of POST url: http://server?api_key=123123&arg_1=234&timestamp=1424453701&api_sig=4glkj4 api_sig is generated by hashing the string api_key=123123&arg_1=234&timestamp=1424453701!!SECRET123 (see SECRET123 as secret API key) The script should neither require the installation of any software nor any user interaction.