Extensible Messaging and Presence Protocol (XMPP) is a communications protocol for message-oriented middleware based on XML (Extensible Markup Language). The protocol was originally named Jabber, and was developed by the Jabber open-source community in 1999 for near real-time, instant messaging (IM), presence information, and contact list maintenance. Designed to be extensible, the protocol has also been used for publish-subscribe systems, signalling for VoIP, video, file transfer, gaming, Internet of Things applications such as the smart grid, and social networking services. Unlike most instant messaging protocols, XMPP is defined in an open standard and uses an open systems approach of development and application, by which anyone may implement an XMPP service and interoperate with other organizations' implementations. Because XMPP is an open protocol, implementations can be developed using any software license; although many server, client, and library implementations are distributed as free and open-source software, numerous freeware and commercial software implementations also exist. [block:block=4] XMPP-based software is deployed widely across the Internet, and by 2003, was used by over ten million people worldwide, according to the XMPP Standards Foundation. For the most recent listing of valid Clients, be sure to check here: httpxmpp.org/xmpp-software/clients/ While this page acts as a mirror for this information, the xmpp.org site is the most valid location of information. Source: xmpp.org xmpp on wikipedia
# Applications
On the Raspberry Pi you can easily run a webserver for your site. We have also tested open source software, Drupal and Wordpress, on Raspberry. Results show that this device works perfectly. This service will pay off especially in cases where you prefer commonly shared hosting, and want to be sure that your server only runs your applications. Plus, you can customize the server to your own exact needs, and install applications that otherwise would not be possible on hosting. We recommend configuration for Apache 2 webserver and PHP-FPM or NGINX but the final decision is of course up to you. Did you know that on Raspberry Pi you can run load-balancing and maximize the availability of your website (High availability) ? [block:block=4] How does it work ? To start using this system you need 2x Raspberry Pi for load-balancing with HAProxy (1x active, 1x passive) and at least 2x Raspberry Pi (or more) for your website. However, this page cannot contain comprehensive information on how to configure the system or how the system works. It is not designed for it, and analysis of the client's needs is always needed. If you are interested in more information or operation of this system, whether on Raspberry or any other system (VPS,please do not hesitate to contact our technical support

VPN is a virtual private network. It is created by software or hardware devices on the server. Clients across the Internet can create a secure tunnel connection cable replacement and wireless connections. VPN seems to be as a local LAN. Through this network you can fully and safely, with minimal costs, connect your branch office LAN network anywhere in the world. Many of us have a wifi router at home with an external disk or printer attached. Such a system has many advantages. You can easily share files, use Remote Desktop, put into operation a FTP server, or anything else. In large companies it is a good network matter of course. A necessary requirement is however a network access. I do not mean a situation where you're sitting in the office and you plug a cable into your laptop, that is quite a trivial matter. But, what if you need to print something on a printer located on the boss's table, update the status of goods in stock, have permanent access to a server, spreadsheets or download email from MS Exchange server? In the office, it is not a problem. Now, what if you are 1000 km away, and you have a laptop data card or are on holiday and you are limited by local conditions? Then there is VPN. In technologically advanced societies it is already in place - on the desktop icon you have a laptop with internet connection "to the company ." On the double click, wait a few seconds - and you're in business. Why not use the same comfort on a home network? [block:block=4] With the concept of VPN you can meet in many similar ways. In this text, the term VPN we have in mind is an encrypted connection (tunnel) to the local network over a public network (internet). Wherever you are with a laptop connected to the internet and create a tunnel you will work in exactly the same way as when you connect at work via cable or via Wi-Fi. You will see the workgroup computers, network printers and shared documents. If your home computer is using Remote Desktop, log on to it from anywhere

You need at least two Raspberry Pi to operate a supercomputer: a parallel processing on Raspberry Pi is possible thanks to the ultra portable MPICH2 (Message Passing Interface). For such involvement there must be only one public IP address. On the other Raspberry Pi there are only local addresses, so you can in this configuration to grant a discount -6 Euro per year for all the Raspberry Pi in the local process. This is good news for all who want to create a supercomputer. Thus, for each additional Raspberry Pi supercomputer you pay only 30€. [block:block=4] In the event that you send us your own Raspberry Pi, you save money on the installation of the system. In another case, however, we charge a small fee for installation. Basic installation of supercomputer system on Raspberry Pi is 9€ and each other Raspberry Pi in supercomputer is only 4€. This is a one time fee for the administrator. Another possibility is that your system is installed and set up on their own. How to make supercomputer visit: University of Southampton Steps to make a Raspberry Pi Supercomputer YouTube Southampton video
Why not take advantage of Raspberry Pi monitoring of your servers or other devices connecting SNMP, etc. A very popular monitoring software including plotting is, RRDTools, and is built on for example, CACTI . Alternatively, other open source software such as ICINGA or NAGIOS can be used for monitoring. [block:block=4]
Raspberry Pi can of course be used as a standalone mail server POP3, IMAP and SMTP. For webmail you can use Squirrelmail or in the last years very popular RoundCUBE. [block:block=4]
High-quality hardware and a good internet connection is the first prerequisite for the operation of a DNS server. Raspberry PI gives you the assurance of quality hardware, and in our data center it will be connected to a high-quality line with the availability of 99.9% For minimal cos,t a highly available DNS server can be built right here on Raspberry PI. [block:block=4]