How to ensure Sitecore all traffic is serverd over SSL/TLS.

Update Web.config add following configuration:

<system.web>
    <httpCookies httpOnlyCookies="true" requireSSL="true" lockItem="true" />
</system.web>

This configuration:

1. Ensures that cookies are secure across your site
2. Ensures that a client-side script cannot read the cookies
3. Prevents any additional configuration from overriding these settings.