How to fix the ssh connect for a password promt wait so long?

I have a AliYun VPS, that ip 42.96.166.148, these days while I using the linux terminal client "lxterminal" to connect to it, I should wait so long, it is a waste of time.So, Why ? Who is the murder.

Because I have ever configed the /etc/ssh/sshd_config with the option "GSSAPIAuthentication" and "GSSAPICleanupCredentials" to "no", so this time I changed it directely change the value to no, and then I found that while I use the command "ssh root@42.96.166.148", the password promts me so quickly. Yeah, save a lot of my time.

Also, I have do a research to GSSAPI,
Reference:
http://germanrumm.eu/fixing-ssh-login-delay-how-to-disable-gssapi-with-mic-on-ubuntu-linux/

The author suggests that you should change the GSSAPIAuthentication to no.

And, the reference:
http://drsavoye.blogspot.com/2010/04/fixing-slow-ssh-prompt.html
the guy has suggests that change both the GSSAPIAuthentication and GSSAPICleanupCredentials to no.
At this time, I think the GSSAPI is a shell to protect the password and pubkey authentication.

I have a question now, what is GSSAPI?