User Manual

Introduction
Trango Broadband Wireless — User Manual Access5830 Rev. D
Page 1
Section 1 Introduction
Your Trango Broadband M900S radio system provides a reliable and robust means to deliver broadband access and wireless Ethernet
connectivity to a wide geographic region. This section will familiarize you with basic operational concepts as well as an overview of the
hardware and the various components of the M900S system.
Overview
The M900S is a highly versatile and cost effective outdoor point-to-multipoint solution for wireless broadband service providers
enterprise connectivity applications. The M900S delivers 3 Mbps over the air, and operates in the 900 MHz ISM band. Each
radio includes an integrated built-in 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
The M900S system is classified as a Layer 2 multi-point bridge. Authentication of SUs is performed using a secure, proprietary
method at the MAC level, and thus all forms of Ethernet traffic and unlimited IP addresses will pass seamlessly over the system.
There is no limitation on the number of IP addresses or hardware devices that an individual SU may have physically connected to an
M900S radio.
Both APs and SUs can be easily configured and managed (either locally or remotely) through built in serial and Ethernet
interfaces, along with a web browser provisioning tool for quick set up and deployment. The M900S radios are powered using
"Power over Ethernet" for ease and low-cost installation. Both APs and SUs feature a handy "site survey" tool to check for
interference.
The M900S system consists of two types of radios: Access Points (AP) and Subscriber Units (SU). The AP unit acts as a hub in a star
configuration wireless multipoint network supporting up to 126 subscriber units. The AP delivers wireless broadband service (Ethernet
connectivity) to one or more SUs according to a proprietary adaptive dynamic polling algorithm called SMARTPolling™ 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 1-1 Typical Point-to-Multipoint Deployment
The M900S AP provides a host of comprehensive tools and functions. The AP typically resides at the center of the point-to-multipoint
(PMP) network and performs all management functions including the allocation of bandwidth for all associated SUs.
SmartPolling™ Overview
One of the major advantages of the M900S system is the ability of the AP to handle multiple SU connections and share the
3 Mbps data throughput very efficiently. Bandwidth allocation is managed by the AP’s SMARTPolling algorithm according to
provisioning rules set up by the system administrator. The AP polls each SU in a round robin format to determine if the SU
has data to transfer. The SU only transmits the data “upstream” to the AP when the AP gives authorization via a “transmit
grant”. The SU parses every “downstream” data packet from the AP and identifies packets intended for it. In order for an
SU to communicate with an AP, the system administrator must first add the MAC address and ID number of the SU to the
user database in the AP. The SmartPolling algorithm will poll active SUs more often thus making the most efficient use of
the 3 Mbps bandwidth. Several other parameters are considered in the SmartPolling algorithm including Committed
Information Rate (CIR), Maximum Information Rate (MIR), and Priority Setting.