Esomo is developed on the basis of the FreeBSD 6.2 network operational system (BSD UNIX family). The program contains an optimum set of adjusted and ready-to-use services, which allow users to quickly set up a reliable internet access server. All of the network services are implemented on the core level, and this makes Esomo a highly efficient program, for it minimizes consumption of processor time and RAM memory space.

The Esomo bundle consists of two main parts: server and client.

The server part of Esomo combines functions of a router and a billing system. This part includes:

 

	The module for tracking and limiting of the incoming and outgoing traffic	Keeps a record and limits incoming and outgoing traffic for paid and free resources; Tracks and limits the connection time; Disconnects a user from the network when traffic limit is exceeded.
	Firewall	Protects a local network from external attacks and prevents from an unauthorized access to the internet.
	VPN server	Creates a VPN connection between a user computer and the Esomo server. VPN works in a base mode (with no encryption) and is compatible with all the operational systems that support VPN. The connection is operated by the standard system drivers on a user computer. VPN protects a user from false IP addresses created for unauthorized internet access, as well as prevents wiretaps. The MPPE encryption method is used along with IPSEC and address pools (i.e. dynamic creation of nodes on the server).
	NAT service	Connects several local network computers to the internet via the Esomo server using a common IP address. This allows hiding the local network computers from outside security threats.
	DHCP server	Automatically designates IP addresses to the local network computers.
	HTTP redirector	Redirects an unauthorized user to the authorization webpage.
	autoVPN	An ActiveX component, which, once downloaded to a user computer, automatically adjusts a VPN connection between the user computer and the Esomo server.
	HTTP server	Stores the service data and autoVPN.
	FreeRADIUS	User authentication server.
	PostgreSQL	A multi-level database, which stores all the information necessary for Esomo's functioning. Adjustment and administration of the Esomo server are accomplished through viewing and changing this data with the help of Esomo Admin (Esomo's front end).

 

Esomo's server part should be installed on a separate computer. Such a computer must have at least two network cards: one of them should be connected to the local network, while the other one is connected to the internet. Remote adjustment and administration of the server is accomplished via Esomo Admin, i.e. the client part of Esomo.

Front End - Esomo Admin is a win32 application with an easy-to-use graphical interface. The application is used for remote adjustment and administration of the Esomo server. Esomo Admin does not require installation, and therefore it can be run on any computer operated by Windows (version 98/NT 4.0 and higher) and connected to the Esomo server. The program can be run not only from any hard drive, but also from any portable data medium (for example, flash-card). This makes administration of Esomo more convenient and secure.

A diagram of a typical network with Esomo: