Internet Service Providers

Building an ISP is so specific and unique in each case that there are no predetermined rules and recommendation. Nevertheless, the main component of an ISP setup is an Internet backbone.

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The system architecture is based on an asymmetrical satellite access to the Internet and provides the following:

• Connection to a first tier backbone connections and/or to Internet traffic exchange point.
• Traffic peering between different system components.
• Traffic filtering and node protection from network attacks.
• Caching Internet content.
• Distance monitoring access.
• Redistribution of incoming and outgoing Internet traffic.

Access server
Access server (a modem pool) is responsible for providing basic services of an ISP. It provides traffic flow to commuted access users (dial up) and leased line customers.

Cache server

• Provides caching of Internet content and objects requested by users from the Internet.
• Improves productivity: decreases load on the backbone and download time of Internet content for users.
• Decreases expenses: less traffic flow that results in lower cost of Internet access.

Firewall
Provides security from unauthorized access to critical servers and services, protecting confidential information from being stolen. A firewall can be both a software (firewall software etc.), and a physical device (CISCO Pix Firewall etc.)

Authorization, Billing
Authorization and billing are defined as critical services and provide basic functions such as user authorization to use the ISP services and calculation of usage statistics.

WWW, FTP, MAIL, DNS
These servers are installed if necessary.