SIMREX DataMover ESS, Руководство пользователя

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6 DataMover ESS User’s Guide SIMREX MAN.ESS-01, Rev. F
SIMREX Corporation
1.1.2 Differences Between ESS and ESS-II
The ESS and ESS-II Transceivers, while similar in many respects, do
have some key differences. The main differences are summarized in
Table 1-2 :
Table 1-2. Transceiver Differences (ESS vs. ESS-II)
NOTE: The DataMover ESS and DataMover ESS-II transceivers are
not over-the-air compatible.
1.2 APPLICATIONS
The following sections provide illustrations of typical transceiver instal-
lations. This is meant as an overview only. It is recommended that a net-
work manager be involved in all installation planning activities.
1.2.1 Wireless LAN
The wireless LAN is the most common application of the transceiver. It
consists of a central control station (Access Point) and one or more asso-
ciated Remote units, as shown in
Figure 1-2 on Page 7 . A LAN provides
communications between a central WAN/LAN and remote Ethernet
segments. The operation of the radio system is transparent to the com-
puter equipment connected to the transceiver.
The Access Point is positioned at a location from which it can commu-
nicate with all of the Remote units in the system. Commonly, this is a
high location on top of a building or communications tower. Messages
are exchanged at the Ethernet level. This includes all types of IP traffic.
A Remote transceiver can only talk over-the-air to an Access Point unit
(AP). Peer-to-peer communications between Remotes can only take
place indirectly via the AP. In the same fashion, an AP can only talk
over-the-air to associated Remote units. Exception: Two APs can com-
municate with each other “off-the-air” through their Ethernet connectors
using a common LAN/WAN.
Characteristic ESS ESS-II
Data Rate 256/512 kbps 512 kbps/1 Mbps
FCC Certification
Type FHSS DTS
Encryption RC4-128 AES-128
Channel size 316.5 kHz 600 kHz
Channel operation Zones Channels
Firmware Specific for ESS Specific for ESS-II