week Ten session: 3 Reflection

In this week last session we learn about

Instant Messaging (IM) is a form of real-time direct text-based chatting communication in push mode between two or more people using personal computers or other devices, along with shared clients. The user's text is conveyed over a network, such as the Internet. More advanced instant messaging software clients also allow enhanced modes of communication, such as live voice or video calling and inclusion of links to media. Instant messaging (IM) falls under the umbrella term online chat, since it is also text-based, bi-directionally exchanged, and happens in real-time. IM is distinct from chat in that IM is based on clients that facilitate connections between specified known users (often using a contact list, buddy list, or friend list). Online 'chat' includes web-based applications that allow communication between (often directly addressed, but anonymous) users in a multi-user environment.

Skype: Skype ( /ˈskaɪp/) is a proprietary voice over Internet Protocol service and software application originally created by Niklas Zennström and Janus Friis, and owned by Microsoft since 2011.

The service allows users to communicate with peers by voice, video, and instant messaging over the Internet. Phone calls may be placed to recipients on the traditional telephone networks. Calls to other users within the Skype service are free of charge, while calls to landline telephones and mobile phones are charged via a debit-based user account system. Skype has also become popular for its additional features, including file transfer, and videoconferencing. Competitors include SIP and H.323-based services, such as Empathy, Linphone, Ekiga  as well as the Google Talk service.

Skype has 663 million registered users as of September 2011. The network is operated by Microsoft, which has its Skype division headquarters in Luxembourg. Most of the development team and 44% of the overall employees of the division are situated in the offices of Tallinn and Tartu, Estonia.

Unlike other VoIP services, Skype is a peer-to-peer system rather than a client–server system, and makes use of background processing on computers running Skype software; the original name proposed – Sky peer-to-peer – reflects this.

Some network administrators have banned Skype on corporate, government, home, and education networks, citing reasons such as inappropriate usage of resources, excessive bandwidth usage,and security concerns.

VRVS: Originally developed at CERN and now maintained by Caltech , the Virtual Room Videoconferencing System (VRVS) is a free, Web-based videoconferencing system that provides high-quality video and audio plus text chat to a large number of simultaneous users. Originally developed for the high energy and nuclear physics communities, VRVS has extended its service to other academic and research areas.

The VRVS system is made up of several communities, each of is composed of a list of Virtual Rooms.

Rooms must be reserved in advance using the integrated booking system that also provides world time conversion and e-mail notification to selected participants.

Users can select any one of four ways to participate in a meeting:

via the user's H.323 external box

via the user's H.323 software client

via the VIC/RAT/VAT software provided by VRVS

via the QuickTime Player.

VRVS can as be used as Personal Access Grid Node.

VRVS works under Windows, Macintosh, Linux, Solaris and Irix operating systems.