How to make SSH connection between servers using public-key authentication?

How do I make a limited account on a server connection an administrator account using dos or any other method?

• The computers at my school's lab are all connected to servers.The thing is, all the user accounts have been given limited access by the mother server leaving me with so many disabilities. I'll be happy if someone teaches me how to make user accounts connected to a server which have limited access become accounts with administrator privileges via the dos prompt or other means in exception of downloading third party programs because I can't install nothing. Please help.

• Answer:

  School labs have all servers connected, to monitor the use of the students, faculty, and any one else who uses the computer. In order for you to be able to change the settings, you would have to be an owner of the computer, which you are not, because the school is. They do it on purpose, because downloading third party programs would be an open invitation to spyware, malware, trojans, and any other malicious or spy software that is out there. It could damage the computers(which would be costly), could potentially risk the schools reputation or breach the privacy of the students(which could mean alot of lawsuits from angry parents). With your own personal computer, however, you certainly can make changes and limited access to accounts, but it would vary depending on which type of computer and what version, you have.