PUBLIC SAFETY - a NIMS smart practice.
IN ALLEGANY COUNTY, MARYLAND: A MUNICIPAL WIRELESS
NETWORK PROVIDING ENHANCED CAPABILITIES FOR PUBLIC SAFETY
AGENCIES.
« Back
ALLEGANY COUNTY, MD
Allegany County, Md., has found a way to provide its response
agencies with advanced telecommunications services such
as enhanced interoperability, mobile high-speed data terminals
and more by using innovative fixed wireless technology.
The countys challenging terrain and the economics
of a rural population base has made wireless systems or
establishing newly wired infrastructure throughout the county
difficult to achieve.
The Allegany County Network, AllCoNet2, is a carrier class
communication network that provides high quality communication
services to public safety, government, educational, commercial
and residential users. AllCoNet was originally developed
by the Allegany School System to bridge the Digital
Divide in a cost effective manner to improve educational
opportunities.
As AllCoNet2 evolved over time, additional government
agencies such as the libraries, city and county government
and public safety agencies adopted it as a cost-effective,
reliable solution to the need for interoperable communications
including voice, data and video. This means that construction
and operational costs can be shared among a number of groups
rather than being borne entirely by Allegany Countys
public safety agencies.
Technical Details:
- Coverage: AllCoNet provides nearly ubiquitous
coverage over the mountainous terrain of Allegany County.
- Two-way Radio Interoperability: AllCoNet can
selectively bridge the audio of disparate public safety
two-way radio systems when intersystem communications
is required without the expense of updating each individual
radio, adding more radios to vehicles, or constructing
an entirely new two-way radio system to enhance interoperability.
- Mobile Broadband: AllCoNet operates a 900 MHz
mobile broadband system that allows each cruiser, fire
engine and other public safety vehicles to have a secure
high-speed connection (1.5Mbps) that supports IP Voice,
video and data access to their respective headquarters.
- Flexible Operations: New connections into AllCoNet
can be added in as little as one hour, requiring only
a quick setup of the remote radio and authorization in
the Network Management System (which can be skipped if
the radio is pre-authorized). This allows broadband connectivity
to be added at the scene of an event and that bandwidth
can be further projected within the event
through the use of localized Wi-Fi or other wireless technologies.
- Multi-Service: AllCoNet supports both IP and
TDM (T1 and DS3) services to accommodate both legacy-trunked
radio systems and newer IP-based communication systems
on the same platform. AllCoNet supports voice, video and
data applications and has the capability to appropriately
prioritize and manage Quality of Service to
accommodate the characteristics and requirements of each.
- Self-contained: For day-to-day functionality
within its service area, AllCoNet does not depend on any
out of area services, unlike many wireline
networks that depend on monitoring, administration and
repair (one minor exception is that AllCoNet currently
uses timing references synched to the Global Positioning
System [GPS] satellite constellation). All monitoring,
administration and repair for AllCoNet is performed locally.
- Rapid Reconfiguration: If normal backhaul links
are severed, additional backhaul links can be connected
at any point in the network and that capacity made available
to all network nodes.
- Environmental, Monitoring and Control Capabilities:
AllCoNets coverage makes it possible to integrate
the functions previously performed by dedicated (and expensive-to-maintain)
Supervisory Control and Data Acquisition (SCADA) systems.
This makes possible a costeffective dispersed placement
of monitoring and control systems for environmental monitoring
(including Nuclear, Biological, Chemical sensors), weather,
monitoring, including video, of critical but remote infrastructure
such as pipelines and reservoirs. With solar power systems,
such remote nodes need not rely on any infrastructure.
- Layer 2 Separation: AllCoNet separates traffic
at OSI Model layer 2 to provide absolute, secure and separate
management and transmission of public safety data and
voice. This enables the backbone to have multiple virtual
networks, with each layer 2 connection having its own
prioritization, bandwidth limits and other characteristics
that control its ability to utilize network resources.
Public Safety networks can be configured to have priority
over all other traffic on the network in times of emergency
or disaster.
- Security: AllCoNet is fully encrypted at a minimum
AES128 (capable of AES256). Antispoofing technology denies
all unauthorized devices access to the network. The management
system monitors the network for unauthorized intrusion
with a sophisticated intrusion detection system and alerts
the appropriate personnel in the event an attempt is detected.
- Prioritization: The network prioritizes critical
traffic over other traffic on the network by user, by
application, or a combination of both. AllCoNet supports
multiple levels of prioritization to ensure that the most
important applications or users have the network access
and bandwidth that are required for successful communication.
- SONET Ring Architecture: AllCoNet uses a SONET
technology as a backbone to provide carrier grade availability
and reliability. The network provides all the features
and benefits of a telecommunications carrier with the
cost-effectiveness of wireless infrastructure as opposed
to wired infrastructure.
- Reliability: The network is designed so that
there are no single points of failure. Architecture includes
geographically diverse backbone paths and capability to
re-home premise radios to a secondary tower access point.
- Redundancy: All critical components are designed
to be fully redundant, including power, data hardware
and towers.
- Availability or uptime (99.999%): Because of
the redundant design and geographically diverse backbone
paths, the network boasts high availability comparable
to the best carrier-grade networks.
- Quality of Service (QOS): The AllCoNet treatment
of packets through prioritization and bandwidth management
provide for guaranteed QOS. In the event of a disaster,
where security and pubic safety applications must have
priority, the AllCoNet network facilitates this need elegantly
and easily.
- Grade of Service (GOS): AllCoNet uses traffic
shaping and traffic policing to make sure the cell packets
and IP content meet their performance contracts. Cells
are tagged for their various prioritizations. Cell Loss
Priority (CLP), Partial Packet Discard (PPD) and Early
Packet Discard (EDP) allow cells to meet the contracted
performance.
- Self-adjusting network: AllCoNet allows the network
to look forward and adjust bandwidth as required through
variable bit rate (VBR) specification. When a virtual
path is created, an average cell rate is specified, which
can peak at a certain level for a maximum interval before
becoming problematic. VBR has real-time and non-real-time
variations, and is used for "bursty" virtual
data circuits. This allows the network to adjust the flow
of packet cells to more important packets and maintain
those flows as necessary.
- Self-balancing network: The AllCoNet network
is intelligent enough to adjust available bandwidth to
guarantee bandwidth allocation for certain types of virtual
private circuits that require a specific amount of bandwidth,
or just the right to use available bandwidth through the
following parameters: CBR - Constant bit rate: a Peak
Cell Rate is specified, which is constant, often with
a higher priority; or UBR - Unspecified bit rate, where
the circuit is allocated up to all remaining unused transmission
capacity. Priority for UBR-specified virtual circuits
is low. CBR circuits are used for applications such as
video surveillance or monitoring that require a constant
data stream. UBR circuits are typically used where large
bandwidth is desired but is not critical.
- Latency (packet delay): Network latency on the
AllCoNet network backbone is less than five milliseconds
from any point to any other point on the network. Applications
such as IP voice and video require low latency in order
to work acceptably.
- Jitter: Jitter on the AllCoNet network is so
low that it cannot be measured. Jitter describes the order
in which packets arrive at their destination, and can
severely affect voice and video transmission.
- Efficiency: The AllCoNet backbone is robust,
and even at 100% utilization, experiences virtually no
packet loss or decrease in efficiency or performance.
- Scalability: AllCoNet allows for seamless scalability;
if additional capacity is needed in a particular area,
a new tower can be added and quickly integrated into the
network with very little impact, increasing the capacity
of the network as much as needed.
- Ready for IPv6: Because the technology underlying
AllCoNet operates at Layer 2, AllCoNet is
inherently ready for advanced Layer 3 transport
technologies such as Internet Protocol Version 6 (IPv6).
IPv6 offers a number of advanced technology and security
features that are of particular interest to, among others,
the US Department of Defense.
- IP Voice: AllCoNets inherently low packet
loss, jitter, QOS and prioritization capability combine
to make AllCoNet an excellent network for the use of IP
Voice. AllCoNets ability to provide legacy telecommunication
services such as T-1/T-3 make it easy to connect conventional
telephony systems such as Private Branch Exchange (PBX)
systems to use IP Voice.
- Effective Backhaul: The network backbone design
eliminates the need for expensive backhaul circuits to
connect edge devices such as Wi-Fi or Mesh radios. Instead
of using intermediate aggregation points or expensive
private line services, these devices are a single hop
from the network core. The QOS and prioritization capabilities
of the backbone are extended directly to the Wi-Fi/Mesh
radios which enhances the Wi-Fi cloud beyond typical Wi-Fi
deployments. AllCoNet networks edge access
is large enough to be considered as backhaul
in other municipal deployment architectures.
- Upgrade-ready: AllCoNets internal systems
are layered and coupled so that new technologies
are easily integrated, such as systems for the new 4.9
GHz broadband public safety band, 700 MHz, WiMAX and others.
- Fiber Interoperability: AllCoNet can be thought
of as a wireless fiber distribution system.
Where interoperability with fiber makes sense, such as
a very high bandwidth user or a highly concentrated cluster
of users or a problematic wireless environment, AllCoNet
hubs have fiber ports built in. Fiber can then be used
with no reconfiguration of equipment.
- Cost-effective To Operate: One of the primary
strengths of AllCoNet is that it uses cost-effective commercial
off-the-shelf (COTS) broadband radio systems, but is able
to achieve considerably more robust Quality Of Service
(QOS) and Security than is normally possible with such
systems.
- Sustainable Economic Model: Once an AllCoNet
network is constructed, ongoing operations are economically
sustainable because the network can provide services to
commercial customers who pay fees to make use of the network.
Commercial use of the network does not, in any way, compromise
the public-safety usage of the network, and the full resources
of the network are available during an emergency.
- Easily Replicated: AllCoNet-type networks can
be built nearly anywhere an independent, costeffective,
broadband network is needed, and constructed at relatively
modest cost ($5 million for AllCoNet).
Network Management System
AllCoNet comprehensively manages and controls the environment
and the network. Many of the deficiencies in interoperability
and cooperation between key emergency responder organizations
are a result of concerns about control, network complexity
and cost. AllCoNet addresses these concerns through a complete
management platform accessed through a single web-based interface
that can be accessed securely from any browser. It is a companion
to the network architecture described above, and allows each
government entity or provider with a Layer 2 virtual network
to perform multiple functions associated with their own end-user
base including the following features:
- Security Monitoring and Authentication: AllCoNet
has multiple levels of authentication, including radius,
MAC address, PVC, VPN and session management and control.
In addition, the network can detect any connection that
is not encrypted, and can detect any node (even if spoofed)
that is not authorized on the network, and disallow that
node from access to the network. It will also alarm the
Network Operations Center of any attempted breaches of
network security.
- Bandwidth Monitoring and Management: The network
management provides both real-time and historical data
to assist in identifying trends, issues and bandwidth
needs for each virtual Layer 2 network, and overall network
capacity. The system also monitors network latency and
jitter.
- Quality of Service: The management system provides
the tools to set prioritization rules for applications
and users on each Layer 2 segment, as well as prioritization
rules among each of the Layer 2 segments themselves. This
provides the ability for critical applications under emergency
response and public safety to take priority over all other
network traffic as necessary.
- Environmental Monitoring: The system manages
the environment, not only at the NOC, but also at each
of the core towers. It monitors power utilization, temperature,
humidity and status of generator and fuel.
- Backbone Equipment Monitoring and Management:
The management system monitors all hardware employed in
the backbone, including status of all interface cards,
radios, routers and switches, as well as tower downlinks.
It also monitors the SONET network and all of the redundant
components to identify any failover conditions that may
occur. Alerts are set to notify the appropriate personnel
of problems including problem severity.
- Radio Signal Strength and Trend Monitoring: All
radios on the network are monitored full time for signal
strength, uptime and status of other critical radio functions,
including security, encryption and code revisions. The
system allows the network operator to proactively address
problems before network failures occur.
- Provisioning and user management: Provisioning
of new users or radios onto the network is simplified
through the use of templates, which allow radios to be
automatically configured correctly and provisioned with
a minimal amount of user input. The system ensures that
the correct configuration and code revisions for the hardware
are used with every install. Software/firmware upgrades
to all network infrastructure devices can be done remotely
instead of having to manually update individual units.
- Customized Management: In addition to having
the ability to manage the network, the management platform
can also be customized to monitor critical customer premise
equipment such as phone systems, servers and other key
network devices.
For more information about AllCoNet2, contact Jeff Blank,
301-759-2006, jblank@allconet.org.
NIMS Smart Practice: 02-06
NIMS Integration Center, May 2006
NIMS-Integration-Center@dhs.gov
www.fema.gov/emergency/nims
202-646-3850
« Back
|
|
 |
« AES - encryption
(A short introduction)
«
AES - encryption
(Flash Animation)
|
« Technology Overview
Video about network |
|