Security: Ssh-agent
(last edit: 2000-11-22)
                   This agent stores your passphrase for as long as ssh-agent is running.

From the prompt type:

user@host:~#ssh-agent startx

From X type:

user@host:~#ssh-add

Ssh-add will ask you for your passphrase when your identity file requires one.

from the freebsd 3.4 manual:

       Ssh-agent  is  a  program  to  hold authentication private
       keys.  The idea is that ssh-agent is started in the begin-
       ning  of  an  X-session  or a login session, and all other
       windows or programs are started as children  of  the  ssh-
       agent  program  (the  command  normally starts X or is the
       user shell).  Programs started under the agent  inherit  a
       connection  to  the  agent, and the agent is automatically
       used for RSA authentication when logging to other machines
       using ssh.

       [...]

       The agent initially does not have any private keys.   Keys
       are added using ssh-add.  When executed without arguments,
       ssh-add adds the $HOME/.ssh/identity file.  If  the  iden-
       tity  has  a  passphrase,  ssh-add asks for the passphrase
       (using a small X11 application if running  under  X11,  or
       from  the  terminal  if running without X).  It then sends
       the identity to the  agent.   Several  identities  can  be
       stored  in  the agent; the agent can automatically use any
       of these identities.  Ssh-add -l displays  the  identities
       currently held by the agent.
    
       [...]

       The idea is that the agent is run in the user's local PC,
       laptop, or terminal.   Authentication  data  need  not  be
       stored   on   any   other   machine,   and  authentication
       passphrases never go over the network.  However, the  con-
       nection  to the agent is forwarded over ssh remote logins,
       and the user can thus use  the  privileges  given  by  the
       identities anywhere in the network in a secure way.