Most modern browsers will give a warning if an SSL cert has expired or is invalid - as in that it may be a spoof certificate.
One of the most commonly used SSL software packages on the Internet, OpenSSL, suffered a major security flaw in the shape of the [http://heartbleed.com/| Heart Bleed bug]. This left most websites using a certain version of OpenSSL open to an exploit. This incident highlights that no technology is 100% secure and requires constant monitoring.
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'''SFTP'''
When transfering files to or from a remote server it is integral to security to use an SFTP client. This stands for Secure File Tranfer Protocol. In a similar manner to SSL it ensures that the communications to and from the server are not open to external individuals.
An excellent client is [http://cyberduck.io/ Cyberduck]
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'''SSH'''
When connecting directly to a server, for example for command line access, it is imperative to use the Secure SHell protocol. As the telnet protocol provides no level of security and should be disabled. For further information see [http://www.openssh.com/ openSSH docs]. For windows a good client is [http://www.putty.org/ putty] for mac and linux the Terminal can be used.
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