+\subsection{Design Principles}
+\label{subsec:design-principles}
+
+P2P-Tube platform has been designed with a few basic design principles in mind:
+
+\begin{enumerate}
+ \item Provide as much as possible the \textbf{features} needed by such a platform, as they appear on similar platforms from the web.
+ \item Provide to users a familiar \textbf{user interface} which resembles similar platforms from the web.
+ \item Ensure that the platform \textbf{scales} well to a size of a few thousands of users.
+ \item Ensure that the platform is \textbf{general purpose}.
+ \item Make the platform available for \textbf{free} and distribute the code as \textbf{open-source}, encouraging community contributions.
+\end{enumerate}
+
+Being developed in academia, in University Politehnica of Bucharest, P2P-Tube was designed to fit well to our needs. The scalability requirements of a few thousands users, enumerated in Principle 3 above is enough for our Faculty of Automatic Control and Computers. However, despite this product was designed in the academia and fits its needs, we ensure that it can be generally purpose as stated in Principle 4 because of the features incorporated and its user interface tied to Principles 1 and 2.
+
+\subsection{Features}
+\label{subsec:features}
+
+P2P-Tube provides to the users the following features:
+
+\begin{itemize}
+ \item \textbf{Categories}. Video assets can be grouped in \textit{categories} for a better organization of them.
+ \item \textbf{Video plugin switching}. If the user has installed both Next-Share plugins (NextSharePC and SwarmPlayer) he is able to switch between them at any moment from the video watching page.
+ \item \textbf{Users and accounts}. Users can apply for an account by registering to the site. Throughout registration, several fields can be completed, some of them mandatory, some of them optional, defining the \textit{user profile}. Authentication is possible through three methods: \textit{internal authentication}, \textit{LDAP authentication} and \textit{OpenID authentication}.
+ \item \textbf{Uploading video assets}. Logged in users can upload new video assets to the site, which can be seen by others.
+ \item \textbf{Social interaction}. Users can see each other's profiles, comment each other's video assets and vote them. Video assets uploaded by an user can be explored.
+ \item \textbf{Searching}. Video assets can be searched by keywords and the results must be ordered by their relevance. The search can be done in the whole set of videos or in a particular category.
+\end{itemize}
+
+\textit{Internal authentication} is for users that applied for an account by the \textit{Registration} page. There are situations when the platform must be integrated with other services or sites. For example in our university we use P2P-Tube to share videos of technical presentations, courses or social events. We also have Moodle learning platform where students already have an account, so it was desired that users can authenticate on P2P-Tube with the same account credentials from Moodle. This has been achieved thorough LDAP which permits students to authenticate on both sites with the same user name and password, without requiring them to create an additional account. Another way to make users skip signing up is by using OpenID, a standard protocol which allows them to sign in through an account from another site. However, this third party site must support OpenID. So, for example, users that already have an account on Yahoo!, Google, Twitter or WordPress can securely sign in with the same user names and passwords from that accounts. When users log in for the first time using external authentication, like LDAP or OpenID, they must complete their profile.