Introduction·Chapter1 13 Frequently Asked Questions Q: Why shouldn't we use Telnet, Rlogin, RCP and FTP? A: These protocols send sensitive information in clear text, which is vulnerable to packet capture. Q: What is the best alternative to these protocols? A: SSH replaces Telnet and Rlogin, SCP replaces RCP, and SFTP replaces FTP. Q: Can firewalls block my traffic? A: Yes, TCP port 22 must be open for these protocols to work. Q: What are the major differences between SSHv1 and SSHv2? A: SSH v1 has major vulnerabilities that have been addressed by SSHv2. Q: Where can I find a good open source version of SSH? A: OpenSSH is the most popular open source and is available at http://www.openssh.org. Q: Can I run an SSH client on Windows?