Karlnet Broadband Wireless Internet Unit


Extending Your LAN Within and Beyond Your Building

The Wireless KarlBridge and KarlRouter can be used to provide an access point (bridge or hub) between the popular AT&T and DEC WaveLAN wireless network and an Ethernet network within a building. With the addition of directional antennas LANs in buildings can be connected at a full 2 megabits/second up to 3 miles apart (10 miles with optional RF amplifier).

CellWave II (No Base Stations)

KarlNet's exclusive CellWave II feature expands wireless connections beyond the simple point-to-point configuration. The CellWave II algorithm compresses and reliably routes Ethernet packets to the appropriate bridge/router overcoming the performance and packet loss problems associated with most wireless bridges. With the CellWave II feature, LANs can be extended to several buildings. In the standard CellWave II configuration each wireless KarlBridge or KarlRouter must be able to "hear" each other. Our specially designed high gain omni-direction antennas are needed in most situations and the cell cannot typically be larger than 10 miles in diameter.

CellWave II (With Base Stations)

With a base station configuration, several buildings can be connected in a cell with one building bridge/router being designated as the base station. The only requirement here is that each satellite station be able to communicate with the base station. It is the base stations responsibility to manage the data flow in the cell, repeating packets when necessary. The satellite stations are usually located within 7.5 miles of the base station creating a cell up to 15 miles in diameter.

KarlBridge/KarlRouter Base Station Capability:

The KarlBridge/KarlRouter has a special KarlNet pioneered reliable data communication algorithm to allow multiple buildings to network together properly. This algorithm is called CellWave and it eliminates the problems associated with wireless packet loss. One CellWave mode of operation is where all wireless buildings can communicate with a base station but not necessarily each other.

With the previously mentioned CellWave Mode (No Base Station) setting there is a requirement that all wireless stations be able to transmit to and receive from ALL other stations in the wireless network. This is not always possible due to the particular topology and terrain. The Wireless KarlBridge/KarlRouter has a special mode where one of the wireless nodes can be setup as a base station and all others can be setup as "satellite" stations. In this configuration the only requirement is that each satellite station be able to communicate with the one base station. The base station is responsible for repeating packets that need to travel between satellite stations.

The performance of this approach can be improved if the base station is connected to the most heavily loaded file server or wired network access point. This is due to the fact that data flowing from one satellite to another satellite station must be repeated (retransmitted) by the base station using more of the wireless bandwidth. Data packets flowing from a satellite station to the base station are transmitted directly without the need to be repeated.


Prepared by;
Doug Karl (Click here for bio)
Vice President in Engineering
KarlNet Inc.
88 East Oakland Avenue
Columbus, OH 43201
Paging: 614-631-1275
Director Networking and Communications
Ohio State University
Columbus, OH