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Ubuntu Linux download and install Skype Software

Q. How do I install skype software under Ubuntu / Debian Linux?

A. Skype is proprietary software that allows you to make calls over the Internet using your computer. Skype uses decentralized peer-to-peer technologies, so your calls do not go through a central server, but through distributed servers and other users. It uses its own proprietary communication protocol to achieve this. In addition, all communications are encrypted from end to end so that others cannot listen in. The Skype software is free to use, but it is not free software; the source code is proprietary and not available for modification.

How do I install skype software Repository?

Click on System > Administration > Software Sources
Ubuntu Linux download and install Skype Software

Click on Third Party Software Tab
Ubuntu Linux download and install Skype Software

Click on Add button to add skype Repository:
Type the following APT line:

deb http://download.skype.com/linux/repos/debian/ stable non-free

Ubuntu Linux download and install skype
Click on Add Source button > Click on Close > Reload button

How do I install skype software?

Open terminal and type the following command:
$ sudo apt-get install skype
Type y when you see following message:

Install these packages without verification [y/N]? y

You can now access skype from Application > Internet menu.

Adding Skype for Linux Repositories From Command Prompt

If you don't want to use above GUI method for Linux repositories, login as the root user. Add this line to the end of your /etc/apt/sources.list file:

deb http://download.skype.com/linux/repos/debian/ stable non-free

Then run apt-get update to sync to the latest repository and install the latest version of Skype on your computer:
$ sudo apt-get update
$ sudo apt-get install skype

Q. Can you example how can I install telnet service or server under Linux or FreeBSD operating system?

A. TELNET (TELetype NETwork) is a network protocol used on the Internet or local area network LAN connections.

The telnetd program (telnet server) is a server which supports the DARPA telnet interactive communication protocol. Telnetd is normally invoked by the internet server inetd or xinetd for requests to connect to the telnet port as indicated by the /etc/services file. Usaually telnet listen on port TCP port 23.

Telnet in is insecure protocol and it is recommended that you use ssh server. But some time you really need telnet then first install telnet server as according to version of Linux distribution.

Telnet server installation

WARNING! Installing telnet open your computer to unencrypted network communication, which is a bad idea. If possible avoid telnet; and use secure shell called ssh.

Debain/Ubuntu Linux user type the following command:
# apt-get install telnetd
$ sudo apt-get install telnetdFedora Linux user the following command:
# yum install telnet-server telnetRed Hat enterprise Linux user type the following command:
up2date telnet-server telnetFreeBSD user type the following command:
No need to install new (telnet server) package, it is installed by default (/usr/libexec/telnetd)

Configure telnet server (turn on telnet server)

Again each distribution has its own method to turn on or off telnet service; same applies to telnet UNIX/Linux server.

If you are using Red Hat / Fedora Linux
The configuration file for telnet is /etc/xinetd.d/telnet. To enable telnet server you need to open this file and make sure disable = no read as disable = yes.
# chkconfig telnet onTo start telnet server type command:
# /etc/init.d/xinetd restartIf you are using Debian Linux
The configuration file for telnet is /etc/inetd.conf. By default it is enabled when you install telnet server. To start telnet server type command:
# /etc/init.d/inetd restartIf you are using FreeBSD
The configuration file for telnet is /etc/inetd.conf. Open file using vi text editor and uncomment line:
# vi /etc/inetd.conf
Make sure commented line:
#telnet stream tcp nowait root /usr/libexec/telnetd telnetdRead as follows:
telnet stream tcp nowait root /usr/libexec/telnetd telnetdSave and close the file. Start telnet service:

Enable inetd service so that telnet get loaded:
# vi /etc/rc.confAppend/add following line to configuration file:
inetd_enable="YES"Save and close the file, Rsstart telnet via inetd service:
# /etc/rc.d/inetd restart

Telnet to server (How do I use telnet client?)

You should now be able to telnet to the server from Windows or Linux desktop system. Type the following command to connect to Telnet server:telnet server-ip-address