Unix- TCP/IP Security (7)
Telnet - Virtual Terminal Protocol
- allows users to login to remote systems
- user name and password (unencrypted) required
- port 23
- telnet hostname port
- 21 (ftp), 80(www),25 (smtp),110(pop3),143(imap4)
Rlogin - remote login for BSD and SVR4
- rlogin -l username hostname
- rlogind and rshd will not request a password if a client is from a trusted host or is a trusted user