Digi m10 Technical Overview

3.13 GES-to-Satellite Channels

The RF links that connect an ORBCOMM Gateway GES to an ORBCOMM satellite use a single 57.6-kbps uplink and downlink channel that uses the TDMA protocol. This protocol permits simultaneous RF links between a single satellite and several GES installations within the satellite footprint. It also provides a virtually seamless hand-over of a satellite from GES to GES under the centralized control of the GMSS.

3.14 GES-to-GCC Channels

GES-to-GCC links will operate over 56-kbps or 64-kbps data lines. A typical installation consists of a Channel Service Unit/Data Service Unit (CSU/DSU) with a V.35 interface at both ends. TCP/IP IEEE 802.3 (Ethernet) packet routers, which provide link layer internetworking, connect these interfaces to the GCC and GES facilities. The GES process communicates with the GMSS process using TCP/IP UDP packets.

Digi International, Inc. © 2009

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Digi M10 manual GES-to-Satellite Channels, GES-to-GCC Channels