| 
Component | 
SSH1 | 
OpenSSH | 
SSH2 | 
| 
Server config | 
/etc/sshd_config | 
/etc/sshd_config | 
/etc/ssh2/sshd2_config | 
| 
Global client config | 
/etc/ssh_config | 
/etc/ssh_config | 
/etc/ssh2/ssh2_config | 
| 
Host private key | 
/etc/ssh_host_key | 
/etc/ssh_host_dsa_key | 
/etc/ssh2/hostkey | 
| 
Host public key | 
/etc/ssh_host_key.pub | 
/etc/ssh_host_dsa_key.pub | 
/etc/ssh2/hostkey.pub | 
| 
Client host keys | 
/etc/ssh_known_hosts
~/.ssh/ssh_known_hosts | 
/etc/ssh_known_hosts
~/.ssh/ssh_known_hosts
~/.ssh/ssh_known_hosts2 | 
/etc/ssh2/hostkeys
~/.ssh2/hostkeys/* | 
| 
Remote host keys | 
~/.ssh/ssh_known_hosts | 
~/.ssh/ssh_known_hosts
~/.ssh/ssh_known_hosts2 | 
~/.ssh2/knownhosts/* | 
| 
libwrap control files | 
/etc/hosts.allow
/etc/hosts.deny | 
/etc/hosts.allow
/etc/hosts.deny | 
/etc/hosts.allow
/etc/hosts.deny | 
| 
Authorization for login via public key | 
~/.ssh/authorized_keys | 
~/.ssh/authorized_keys
~/.ssh/authorized_keys2 | 
~/.ssh2/authorization | 
| 
Authorization for login via trusted-host | 
/etc/hosts.equiv
/etc/shosts.equiv
~/.shosts
~/.rhosts | 
/etc/hosts.equiv
/etc/shosts.equiv
~/.shosts
~/.rhosts | 
/etc/hosts.equiv
/etc/shosts.equiv
~/.shosts
~/.rhosts | 
| 
Default keypair for public-key authentication | 
~/.ssh/identity{.pub} | 
SSH-1/RSA:
~/.ssh/identity{.pub} 
SSH-2/DSA:
~/.ssh/id_dsa{.pub} [52]  | 
(No default) | 
| 
Random seed | 
~/.ssh/random_seed
/etc/ssh_random_seed | 
~/.ssh/prng_seed [53] | 
~/.ssh2/random_seed
 /etc/ssh2/random_seed | 
| 
Commands for generating randomness | 
- | 
/etc/ssh_prng_cmds | 
- | 
| 
Kerberos | 
 /etc/krb5.conf
~/.k5login | 
/etc/krb.conf
~/.klogin | 
- | 
| 
Terminal client | 
ssh1
slogin link to ssh1 | 
ssh
slogin link to ssh | 
ssh2 | 
| 
Secure file copy client | 
 scp1 | 
scp | 
scp2 | 
| 
Signer program | 
- | 
- | 
ssh-signer2 | 
| 
sftp2/scp2 server | 
- | 
- | 
sftp-server2 | 
| 
Authentication agent | 
ssh-agent1 | 
ssh-agent | 
ssh-agent2 | 
| 
Key generator | 
ssh-keygen1 | 
ssh-keygen | 
ssh-keygen2 | 
| 
Key add/remove | 
ssh-add1 | 
ssh-add | 
ssh-add2 | 
| 
Find SSH servers | 
- | 
- | 
ssh-probe2 | 
| 
Get passphrase via terminal or X | 
ssh-askpass1 | 
- | 
ssh-askpass2 | 
| 
Server program | 
 sshd1 | 
sshd | 
sshd2 |