Telnet Protocol Control  
 

Establish an interactive terminal session with a server.

Reference

Control Information

Object Name TelnetClientCtl.TelnetClient
File Name CSTNTX12.OCX
Version 12.0.3024.1286
ProgID SocketTools.TelnetClient.12
ClassID B400A760-1864-4B79-B29A-F4F1A882C466
Threading Model Apartment
Help File CST12CTL.CHM
Dependencies None
Standards RFC 854

Overview

The Telnet protocol is used to establish a connection with a server which provides a virtual terminal session for a user. Its functionality is similar to how character based consoles and serial terminals work, enabling a user to login to the server, execute commands and interact with applications running on the server. The control provides an interface for establishing the connection, negotiating certain options (such as whether characters will be echoed back to the client) and handling the standard I/O functions needed by the program.

The control also provides methods that enable a program to easily scan the data stream for specific sequences of characters, making it very simple to write light-weight client interfaces to applications running on the server. This control can be combined with the SocketTools Terminal control to provide complete terminal emulation services for a standard ANSI or DEC-VT220 terminal.

Caution: The Telnet protocol transmits all data, including login credentials, in plaintext and does not provide any inherent encryption. While this control supports optional TLS connections for Telnet, secure Telnet servers are rare in practice. This protocol is still supported for compatibility with legacy systems, but it is strongly recommended that you use secure protocols such as SSH whenever possible, especially when connecting over public or untrusted networks. To establish a secure connection to the server using the Secure Shell (SSH) protocol, use the SshClient control.

Requirements

The SocketTools ActiveX Edition components are self-registering controls that are compatible with any programming language that supports the Component Object Model (COM) and the ActiveX control specification. If you are using Visual Basic 6.0, Service Pack 6 (SP6) is required. We recommend installing all available updates for your development tools. Although the Visual Basic 6.0 runtime is supported on Windows 11, the IDE itself is no longer officially supported by Microsoft. Legacy IDEs and compilers may also require elevated (administrator) privileges to run properly.

The ActiveX controls are supported on Windows 7, Windows Server 2008 R2, and later versions of both desktop and server editions of Windows. For Windows 7, Service Pack 1 (SP1) is the minimum requirement. For Windows 8 systems, the 8.1 update must be installed. On ARM-based platforms, the minimum supported version is Windows 10 build 1709.

SocketTools includes components for both 32-bit (x86) and 64-bit (x64) Windows platforms. All modern versions of Windows are 64-bit, but we continue to include 32-bit components for compatibility with legacy development tools such as Visual Basic 6.0. We also provide native ARM64 ActiveX controls for systems running Windows on ARM. Note that 32-bit applications on ARM run using x86 emulation, and Microsoft no longer supports native ARM32 applications.

If you are using VBScript, Visual Basic for Applications (VBA), or another scripting environment on an ARM-based system, be aware that 64-bit hosts will require ARM64 components, while 32-bit hosts will use x86 components under emulation. This includes applications created with Visual Basic 6.0. To reduce deployment complexity and avoid confusion, SocketTools does not include ARM32 ActiveX controls in its standard redistribution packages but they are available on request for legacy or specialized scenarios.

Distribution

When you distribute an application that uses this control, you can either install the file in the same folder as your application executable or as a shared component in the appropriate system folder. If you install the control in the system folder, it is important that you distribute the correct version for the target platform and it must be registered. If you install the control in the same folder as your executable, it is recommended that you use registration-free activation or COM redirection to ensure that the correct version of the control is loaded by the application.