It is recommend for you to have a secure connection network between your PC and the Gmail server. Let say if you login to Gmail using a public network like wireless or hotspot in Starbucks, someone can tamper or see the sensitive information transferred from your PC to the Gmail server. This is because the network you are using is not secure and is open to everybody.
Non-secure networks make it easier for someone to impersonate you and gain full access to your Google account, including any sensitive data it may contain like bank statements or online log-in credentials.
To check whether you are in a secure connection or not, check that the protocol that being used is https at the address bar. And also, there is a Lock icon at the bottom right corner of your browser (Firefox).
HTTPS protocol at the address bar
When you have both of them, that’s mean you are in a secure connection. No one can tamper or modify or spying on the data transferred between you and the Gmail server. You are now safe and secure to send emails, at least.
Lock icon at the status bar
Enable the function
To enable this function, in Gmail, go to Settings. Under General tab, scroll down to the bottom and tick Always use https at Browser connection. After you clicked on the Save Changes button, Gmail will log you out and you have to login back but now, you will use https protocol.
Take note, when you are in a secure connection, Gmail speed will be decreased. This is because every data that you transfer will be encrypted first before your browser can send the data to the Gmail server.
Please note that selecting ‘Always use https’ will prevent you from accessing Gmail via HTTP (Hypertext Transfer Protocol). In addition, it may make Gmail a bit slower. If you trust the security of your network, you can turn this feature off at any time.
Although it is not necessary to always connect to Gmail in a secure connection, but in my opinion, it is better to have this function enabled. We don’t know, maybe today, tomorrow, or later, someone might able to get our sensitive data just because we are too lazy or don’t want to use the security feature that have been provided by Google.
For more information about this feature, you can read at Enabling the HTTPS setting.