INTERNET Access Service

Leased Channels

Connection to the Internet via leased channels consists in the provision of 24-hour access to the network with allocation of permanent IP address/ Leased lines for the users can be organized in one of the two modes:

• Asynchronous - up to 28.8 Kbps, or
• Synchronous - from 64 Kbps to 2 Mbps and up to 45 Mbps for special projects.

Users are provided with the connection of their workstations and local-area networks to the Internet.

Besides that users receive:

• SMTP e-mail;
• Back-up SMTP mail server of the organization;
• Access to NEWS conference server;
• Possibility to connect NEWS conference server of the organization.

In the issue a customer receives:

• Guaranteed speed of access to the Internet;
• Improvement of connection quality due to organization of point of presence at the nearest Centel network node; it allows to improve physical parameters of the line and reduces its cost;
• The best scalability, both in terms of high-speed channels and in terms of service package.

The scalability ensures possibility to increase the number of connected users (with relevant increase of speed parameters of the channel) and the number of available services. For example, the same communication line can be used for the organization of additional Internet channels. The main principle of the connection is the organization of a leased line between customer's network router and Central Telegraph's node router ("last mile").

Organization of subscriber access to the transport network can be performed:

• Via fiber-optic communication channels;
• Via direct copper wire using xDSL modems;
• Via radio channels with installation of Airspan terminal at customer's premises;
• Via channels leased from other providers to the Centel network node.

Leased channels with radio access

Airtel is a digital radio network with access to Centel network built on CDMA technology.

This mode of connection can be used for the organization of a "last mile" for the subscribers of the Centel network if they can not be connected via cable infrastructure or if their connection via cables requires too much time. For their access to the network we use the equipment produced by Airspan Communications Limited (Great Britain).

Subscriber terminal ensures fixed subscriber radio access and supports 64 Kbps or 128 Kbps (2B) data transfer channels. The system provides radio communication within the range of 20 km (service zone) from the point of presence.

Outdoor subscriber radio unit is fixed on outside of the building and is connected with internal equipment via cable with the length up to 25 m. Internal units use G.703 interface for the connection of user terminal equipment.