Page 184 - DCAP311_DCAP607_WIRELESS_NETWORKS

Wireless Networks

Notes for each designated government entity and public school, a Metropolitan Area Network
(MAN) for inter-governmental connectivity, and a shared infrastructure for Internet access.
Upon review, Orange County found that the wire-line solutions it used in the past were
cost prohibitive and that certain locations were too distant to establish connectivity. In
addition to spanning a large geographical area that contains many obstructions, Orange
County faced a number of technological and logistical challenges associated with their
existing network. These included limited intra- and inter-governmental connectivity, an
inability to share resources and offer consolidated access to high-speed Internet services,
inadequate broadband capacity for new applications, and disparate data and voice systems.
The County also required reliable support for a wide range of bandwidth-intensive
applications, such as voice-over-Internet Protocol (VoIP), geographic information systems
(GIS), video conferencing, video surveillance and distance learning.
Technical Requirements
1. Support for a wide range of applications, including real-time streaming video and IP
telephony Ability to operate emergency services from alternative sites
2. High data rates of at least 10 Mbps
3. Ease of management and maintenance
4. Ability to use existing tower structures within the County

5. Stability in obstructed paths and high-interference environments
6. High security to protect sensitive government information over a broadband network
7. Design for future backbone redundancy
Deployment Detail and Interoperability

Utilizing systems that operate in the 5.8 GHz band, Orange County deployed Motorola’s
wi4 Fixed Point-to-Point (PTP) 400 and 600 Series Wireless Ethernet Bridges to connect 24
locations including administration offices, public schools, the courthouse, the airport, and
police and emergency services.
The County used the Motorola PTP 600 Series radios to construct a subscriber-access
backbone that extends over 30 miles. To overcome radio frequency interference challenges
and path obstructions, Connectorized models with drum antennas were deployed. The
radios were mounted on the County’s existing tower structures, making it easier to expand
the network.
User networks are segmented via high-performance Ethernet switches with virtual LAN and
access control points. The same network solution also supplies all government entities with
Internet connectivity from a 45 Mbps DS-3 link. A security platform that includes firewall
appliances, VLANs, global anti-virus, content filtering and bandwidth management
applications is deployed at each network entry point to protect sensitive government
data. Large users, such as the public schools, utilize Motorola PTP 400 Series radios with
integrated antennas to provide data rates of at least 18 Mbps, exceeding the County’s
expectations. Smaller subscriber sites, such as the Orange County courthouse, use four-cell
Motorola Canopy solutions.
After successful completion of the initial phase, the project was expanded to include many
fire and rescue locations, allowing E-911 to print dispatch reports at the fire and rescue
stations. E-911 sends the dispatch report to the printer located at the fire and rescue stations
that have connectivity.
Contd...

178 LOVELY PROFESSIONAL UNIVERSITY