Default http access advised for G-mails. In 2008 the option was floated to always use https – this system edits or encrypts your mail as passes through your web browser and their servers. The advantages feature protection from data being sneaked by third parties as in public WiFi hotspots.
They had not insisted on https use earlier as the downside https delay the mail transfer because encrypted data travels slower across the web. They had researched this security aspect / latency tradeoff and finally are now turning https on for all.
They are rolling out https defaults for all. If you set your own https preference from G-mail settings, then it is OK. However, if you do not want default https turned on for performance, you can always turn it off at anytime by choosing “Don’t always use https” from the Settings menu.
It has further been decided that G-mail will still encrypt the login page by way of password protection. Google Apps users whose admin never defaulted, their domains to https will enjoy the same options. For more information on account and computer protection, visit: www.google.com/help/security. They have cautioned to off line G-mail over https users, switching to https may cause problems. Therefore know more on how to pass it.