Command line access via SSH or Telnet is available. Servers can also be accessed remotely using the command line-based Telnet and SSH protocols. Other control panels allow direct access using telnet or secure shell (SSH). SecureCRT is a commercial SSH and Telnet client and terminal emulator by VanDyke Software. They can access the CLI from the serial console, telnet and SSH. However, all functionality is available through KVM, serial console or SSH/telnet protocols. It supports several network protocols, including SCP, SSH, Telnet, rlogin, and raw socket connection. On the Internet, telnet and ssh work similarly. OpenSSH is a free implementation of the SSH protocol and is a replacement for telnet. The FTP and telnet command line programs were removed. Both vendors provide a full function TCP/IP stack with applications, such as telnet and FTP. Telnet, Rlogin, and SSH are being used between systems. Host names are used by applications such as telnet, ftp, web browsers, etc. Tools commonly used to perform banner grabbing are Telnet, nmap, zmap and Netcat. The Winlink protocol supports packet radio via a Telnet connection.