AML MT7570 Vehicle Mount Computer - Manual (Page 27)

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USER’S GUIDE MT7570 Vehicle Mount Terminal
VT220
The VT220 was a terminal produced by Digital Equipment Corporation from 1983 to 1987. It was similar
to the earlier VT100 series of terminals, but added support for the Multinational Character Set and came
with a redesigned keyboard, much smaller physical packaging, full support for 8-bit downloadable
character sets, and a much faster microprocessor.
As with the VT100 emulation, AMLcc uses a custom xterm version for VT220 emulation.
IBM 5250
IBM 5250, originally, was a particular model of a terminal device sold with the IBM System/34 minicom-
puter system. Similar to the IBM 3270, it is a block-oriented terminal protocol, yet is incompatible with
the 3270 standard. The term "5250" now refers to the content of the data stream itself; few physical
5250 terminals still exist, although they are still used to provide a "connection of last resort," hard-wired
to the host computer. As ethernet grew, 5250 via the telnet protocol (TN5250) was developed for use
over modern day networks.
5250 is almost exclusively used to communicate with IBM AS/400 and iSeries machines. AMLcc uses a
customized version of the open source project tn5250 for 5250 emulation. tn5250 can be found at
http://tn5250.sourceforge.net.
IBM 3270
Like IBM 5250, the 3270 terminals were closely tied to the mainframes that they were directly connected
to. 3270, however, gave much more control of the presentation and user input to the terminal itself. In
fact, 3270 is more akin to modern web browsers than telnet clients. Just like 5250, as telnet grew to be
the mainstream low level protocol, TN3270 was developed to use 3270 emulation over telnet.
AMLcc uses the x3270 for 3270 emulation. Many options for x3270 are available through it's own menu
system.
RDP - Remote Desktop Protocol
Remote Desktop Protocol (RDP) is a multi-channel protocol that allows a user to connect to a computer
running Microsoft Terminal Services. Based on the ITU T.share protocol (also known as T.128), the first
version of RDP (called version 4.0) was introduced with Terminal Services in Windows NT 4.0 Server,
Terminal Server Edition. It is now a mainstay of Microsoft Windows Professional and Server additions.
Rdesktop provides AMLcc with RDP connectivity. The current version supports up to RDP Version 5.
VNC - Virtual Network Computing
Virtual Network Computing (VNC) is a desktop sharing system which uses the RFB (Remote FrameBuf-
fer) protocol to remotely control another computer. It transmits the keyboard presses and mouse clicks
from one computer to another relaying the screen updates back in the other direction, over a network.
VNC is not used commonly in production environments because of it's high bandwidth usage, and due
to the high quality of newer protocols such as RDP. However, it is very easy to setup one-to-one con-
nections and does not usually require expensive server implementations like RDP.