Regional Networks
Regional Networks compose the lower level of the overall system. The radius
of a "region" varies from dozens to hundreds of kilometers, and mostly depends
on environment conditions such as topography and weather.
Two kinds of units are included in the network. One is known as "User". Us-
ers are the radio-like equipments which are used directly by men to communicate
with others. That is, we can talk with or even see each other or tranceive data
through such an equipment. To accomplish their jobs Users can establish a dire-
ct link with each other, or, when the target User can not be reached, to the o-
ther kind of units called "Relay".
Relays act very much like postmen. They receive data from the sender, and
retransmit it to the recipient. If the recipient is located in the region, data
would be delivered directly; if not, the Relay would send the data to the upper
level of the system, the Global Network. This operation can also be seen in LAN
/WAN architecture of the day. Besides, when the sender wants to "broadcast", a
Relay can do the work by retransmitting the message to all reachable Users[3].
To ensure the secrecy of data, spread spectrum modulation was put to use[4]
. Since DSSS and FHSS holds their advantage/disadvantage, most of which are co-
mplementary, we decided to use the hybrid DSSS/FHSS. In fact, all data flow be-
tween Users (and Relays) are DSSS/FHSS modulated; together with other measures
to deal with eavesdroppers and jammers.
References: [3] The Second Raid Episode.3&4
The Communication post set up by Capt. Blueno served as a Relay
, while Users are used by task force members such as AS units.
All communications during the mission was broadcast. Note that
the beacons lauched by ASs were repeaters, which would retrans-
mit all valid signals they received.
TDD also served as a Relay.
[4] The Second Raid Episode.7
Description by Kaname Chidori.
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◆ From: 140.113.4.15
※ 編輯: ComSoc 來自: 140.113.4.15 (08/17 22:44)