User's Manual

Introduction
Trango Broadband Wireless — User Manual M915S Rev. 1 Page 1
Section 1 Introduction
Your Trango Broadband M915S radio system provides a reliable and robust means to deliver broadband access to a
wide geographic region through wireless Ethernet connectivity. This section will familiarize you with basic
operational concepts, as well as an overview of the various components and hardware of the M915S system.
Overview
The M915S is a highly versatile and cost effective outdoor point-to-multipoint solution for wireless broadband
service providers’ enterprise connectivity applications. The M915S delivers 3 Mbps over the air, and operates in the
900 MHz license free ISM band. Each radio includes an integrated dual polarized (horizontal and vertical) antenna,
as well as a connector for the attachment of an external antenna, such as a Yagi or an omni style antenna. Note: If
you are going to install an external antenna, refer to the M915S Professional Installation Guide. Contact
Technical Support for access to the Professional Installation Guide.
The M915S system consists of two types of radios: Access Points (APs) and Subscriber Units (SUs). Up to 126
subscriber units can be supported by a single AP, which acts as a hub in a star configuration. The AP delivers
wireless broadband service (Ethernet connectivity) to one or more SUs according to a proprietary adaptive dynamic
polling algorithm called SMARTPolling™. The M915S radio units are backward compatible with M900S radios
such that an M915S-AP may be used with M900S-SUs and M915S-SUs may be used with M900S-APs. The main
difference in the design is a better front/back ratio on the internal patch antenna to improve co-location at tower
sites, a redesigned digital section on the printed circuit board, and a new package for the M915S-SU. Network
operators can co-locate multiple APs at a single cell site, thus increasing the aggregate throughput available at each
wireless point of presence (POP).
Figure 1: Typical Deployment
The AP typically resides at the center of the point-to-multipoint (PMP) network. It performs all management
functions, including the allocation of bandwidth for all associated SUs. The M915S AP provides a host of
comprehensive tools and functions.
The M915S system is classified as a Layer 2 multi-point bridge, thus all forms of Ethernet traffic will pass
seamlessly over the system. There is no limitation on the number of IP addresses or hardware devices to which an
individual subscriber unit may be connected.
Authentication of Subscriber Units is performed using a secure proprietary method, which is based on the MAC
address of the subscriber units. In order to establish a wireless link, the MAC address of the SU must be present in
the Access Point’s SUDB.
Both APs and SUs are IP addressable and can be managed remotely across the network. Users can manage the
radios using the telnet command line interface or the graphical HTTP browser interface. The M915S also provides
remote firmware upgrade capability utilizing TFTP. APs include a full-featured SNMP agent for the monitoring
and controlling of both APs and SUs via SNMP.