Secure Terminal Servers/Terminal Servers

Secure Terminal Server/Terminal Server

The Difference Between Device Servers, Terminal Servers, and Console Servers

 

The terms “terminal server,” “device server,” and “console server”

 

can be confusing. They all refer to hardware that connects to RS-232

 

devices and transmits serial data using TCP/IP Telnet, SSH, or a

 

vendor-specific protocol. In fact, these three server types represent the

 

evolution of user demand for information technologies.

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Terminal servers were first introduced to help engineers connect

so-called "dumb terminals" to a host computer over an Ethernet

connection. With terminal servers, data transmission is text based and

is transmitted using Telnet, TCP/IP, SSH, or some other manufacturer-

defined protocol. Terminal servers are designed to enable users to access front-end IT equipment using PPP or dial-in/dial-out,

without using a modem. Terminal servers are generally found in IT environments such as data centers, airports, and banks.

Before the development of Ethernet technology, terminal servers were used to provide access to data using dial-up connections. However, as Ethernet became more common, demand for industrial applications also grew. Most machine-to-machine communication is serial-based, which is effective only over short distances. This makes it difficult to manage all equipment from a central location, which is the foundation of industrial automation. Device servers emerged as a result.

A device server is essentially a simplified terminal server. For industrial applications, serial-to-Ethernet communication does not require sophisticated functionality. Device server manufacturers typically include drivers or COM mapping functions that make things easier for engineers who are not familiar with IT concepts. With drivers installed,

serial devices can be controlled over Ethernet using legacy software, without requiring knowledge of difficult TCP/IP routing techniques or socket programming. Engineers can continue relying on their knowledge of COM/TTY port programming for device control.

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www. moxa . com e - mail: info@moxa . com

IP Systèmes, importateur/distributeur des solutions de communication industrielle MOXA en France Tel : 0820 200 290 (15cts/min)

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Moxa Technologies 6150, 6450, 6250 manual Secure Terminal Server/Terminal Server