Mobile Telnet Client Applications

There are many proprietary as well as open source mobile applications have been developed in the world for various purposes such as network protocol diagnosis, server diagnosis, configurations, etc. In addition there are various VPN client and SSH client applications also available to enable network security. Among them most mobile SSH client software can be downloaded free of charge but mobile VPN clients are totally vendor proprietary products. All of those products are targeted on diagnosing network servers. Although there is no exact Mobile tool purposely developed for doing diagnosis and configurations of network gateways such as routers, switches, etc.

Among those tools in 2008 Strinum Software has introduced a telnet client tool called MobiTerm which runs on Windows 2000 and 2005 mobile operating systems on .NET compact framework. It is a Telnet Client for Windows Mobile/Smartphone with full VT ANSI support. It is optimized for use on Windows Mobile PDA's Smart phones and works great on landscape phones like the Motorola Q. Its custom-developed font allows for full screen (80 cols X 25 rows) to be viewed without scrolling on 320x240 pixel displays. MuTelnet 2.0.1 is another telnet client for J2ME/MIDP mobile devices. It has features of direct TCP connection to remote sites, an ANSI-compatible terminal with off-screen scrolling, an interface adapted to limited input capabilities, bookmark management, command history and control characters support. In order to run this application java compatible mobile platform is needed.

Aleq Berka, a consultant in the Czech Republic has introduced a mobile version of PuTTY, an open source Telnet and SSH client which is fully open source tool for pocket pc. PocketPuTTY is distributed under the BSD license, and supports SSH1, SSH2, Telnet, private key authentication and color terminal emulation. It currently runs on Windows Mobile 2003 and Windows Mobile 5.0, requiring 1 MB of storage, 1 MB of memory, and a network connection. A back port to Windows Mobile Pocket PC 2002 is in the works. Berka has ambitious plans for further work with PocketPuTTY, including Smartphone compatibility, support for VGA and landscape screens, horizontal scrolling, font sizing, and more.

Karl von Randow have developed another Mobile tool called MidpSSH as a SSH and Telnet client for MIDP 1.0 / 2.0 (J2ME) devices such as Java(tm)-capable cell phones and other mobile devices. MidpSSH is based upon Floyd SSH and Telnet Floyd by Radek Polak, who ported the Java (tm) Telnet/SSH Applet to the MIDP platform. MidpSSH adds a GUI and a number of other features to Floyd SSH. This also a free and open source software and it has features of SSH1, SSH2 and Telnet support, Saving session profiles, Macros for entering frequently typed commands, Interactive input mode including typing special keys and control key combinations, Cursor movement using keypad or game control, VT320 terminal emulation and Traffic usage reporting. The latest release of MidpSSH attempts to address the problems Blackberry users have been having downloading and installing MidpSSH. It fixes a protocol error that caused disconnects connecting to some SSH servers and addresses a security bug in the SSH implementation that could be exploited by remote servers.

There is another tool called ZaTelnet Professional which is a Telnet/SSH/SSH1/SSH2/ Serial client for devices supporting Microsoft Compact Framework 1.0 or 2.0. It also emulates terminal VT100 (basically enough for working with Midnight Commander and others console programs). ZaTelnet Professional supports SSH2 authorization by "plain password", "private key file" and "keyboard interactive". The latter mode can be useful in using RSA SecurID tokens. There are four variants of this software available for Pocket PC with MS CF 1.0, Pocket PC with MS CF 2.0, MS Smartphone with CF 1.0 and MS Smartphone 2005 with CF2 for newest devices like MototolaQ, T-Mobile DASH, Samsung BlackJack and so one. ZaTelnet Professional offers extended opportunities for interface customization, such as full screen mode, different display sizes, 240x240, 240x480, 480x480 and 480x640 screen r resolutions, portrait and landscape orientation modes, virtual scrolling screen with adjustable size and different font sizes. Also, ZaTelnet features special floating keyboard for CF1 and CF2. Working with ZaTelnet, user can choose transparent or opaque mode, change keyboard size. Additional convenience comes from transparent floating keyboard, designed specially for Pocket PC version. Additionally, ZaTelnet enables you to change font size for console, virtual screen size and orientation without shutdown session. The client also enables easy saving, editing and restoring of sessions.

In addition ZaTelnet Professional boasts a handful of improvements that make remote administration of Unix and other servers via Telnet/SSH1/SSH2/Serial (cable or BlueTooth) protocol using mobile devices simpler and more efficient. New professional version of zaTelnet features scrolled screen (standard 80x25 and 132x25 plus wide range of custom sizes), fingerprint server test, new crypto library. Also new to this release is key press preview indicator, connection progress indicator, ping utility, various codepages, line input mode, HTTP-proxy with basic web authentication and more other functional improvements.

Joel Ivory Johnson, software developer of RDA providing solutions to clients using Microsoft technologies for web and Windows applications has developed another simple telnet client in .NET compact framework targeting the function of diagnosing server problems by easily connecting to the local network for testing as well as using its only Internet connection to connect to a server from a point outside the local network. This tool is targeted on Windows Mobile 5 Professional devices and the developer has tested the program on both the HTC Wizard (branded Cingular 8125) and an iPaq 4705. And the developer says that it was unable run this software on Motorola Q as a thread related exception that occurred. This tool’s UI was designed to be capable of being displayed on a device with 240x240 resolution but should really be run on a device with at least 320x240 resolution.