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- NET-9.TXT
- LAN USAGE
- ---------
-
- Most of us know how rapidly 1200 baud file transfers can take place over land
- line circuits as compared to packet radio. This is because of three things.
- First the LL circuit is full-duplex. This means receive and transmit can occur
- simultaneously. Second, there are no other users (interference) on the
- circuit. Third, the signal to noise ratio is high.
-
- If one were to upgrade the radio network, it seems logical one should emulate
- to the extent possible, operating conditions found on telephone systems. We
- are further constrained that as a volunteer group, upgrade activites need to
- be done as economically as possible. Up til now, we have not discussed going
- to modem speeds beyond 1200 baud. This is because higher data rates aren't all
- that effective in a simplex network environment. If greater efficiency is
- wanted, it is necessary to establish a radio network configuration satisfying
- the LL system criteria mentioned above. After the basic network configuration
- is installed, attention can be directed towards higher data speeds.
-
- The "ideal" network concept under discussion consists of two components, the
- user access (LAN) port and the backbone trunk.
-
- Access nodes, or LAN interfaces, should be frequency isolated from neighboring
- LAN nodes. The reasoning for this is to eliminate on-channel interference
- from neighboring access nodes and their users. Use of TheNet version 2.08
- or later, nodeware at the LAN node will prevent QRM from node broadcasts and
- accidental user node dumps from congesting the LAN frequency. Also, having the
- HEARD feature available on the LAN node will encourage keyboard-to-keyboard
- contacts across the network and perhaps help in influencing newcomers to stay
- in packet.
-
- To the extent possible, local BBS to BBS forwarding should take place on a
- frequency other than that of the LAN node. With multi-connect software, there
- need only be ONE full-time, full service BBS publically serving the coverage
- area on the frequency of the LAN node. Knowlege of other BBSes with ports
- accessible from the LAN frequency should be subdued. BBS and TCP/IP nodes
- should not be allowed to broadcast on the LAN channel unless there is some
- over-riding networking reason for their presence. Rather than beaconing,
- users should be encouraged to place announcements of their activities on the
- local BBS for all to read.
-
- The above recommendations set the stage for operating a LAN frequency that
- has a minimum of unnecessary overhead congestion and interference. As user
- activity increases, thought can be given to changing the LAN node over to
- duplex-regenerator (packet repeater) operation as this would improve LAN
- frequency throughput. When the duplex regenerator becomes saturated, then
- it's time to consider establishing a second LAN frequency, if one does not
- already exist.
-