second method of communication being a cellular telephone, active multiplex,
derived local channel, one-way private microwave or one-way or two-way
radio frequency link.
In 2002 the NFPA 72 code adopted standards for IP technologies and later
stipulated requirements for use of other communications technologies includ-
ing a packet-switched data network (PSDN) such as IP and Ethernet. Internet
connections are now being used for one and possibly both communications
paths depending on the local AHJ. The Internet connection is faster, more
secure and costs less.
The Internet connection to fire alarm systems uses a dual-destination IP
receiver address, which provides for redundancy, can be encrypted, and can
be tested on a regular and frequent basis. Some central station receivers can
support up to three destination IP receiver addresses for extra equipment
redundancies providing more configuration options.
In addition to supplying another type of communications to the supervising
station, the two-way communications of an IP network are used by technicians
and managers to upload and download information to the control panel, such
as downloading alarm panel data, uploading program updates or performing
system tests remotely. Fire alarm systems are starting to deploy some use of
IP communications protocols in other areas such as between fire panels.
There is still substantial reliance on communications protocols developed
for building automation systems, such as BACnet and LonTalk; however,
these protocols can be easily routed to an IP system and embellishments of
some protocols, such as BACnet/IP, are evolving as the dominance of the IP
protocol is becoming more widely recognized.
Mass Notification Systems
Mass notification systems (MNS) are used to provide real-time descriptive
information and directions to people during fire and nonfire emergencies.
For example, many fire alarm systems have a paging system to notify building
occupants of a fire situation en masse. Mass notification systems cover not
only buildings, but campuses, cities, regions, and the globe; thus, MNS types
are for buildings, wide-area notification, and distributed notification. MNS
are used for fire situations, public alerts, emergency situation conditions and
warnings such as for severe weather.
MNS use a range of technologies to provide information and instructions to
people including speakers, electronic digital-message displays, computer inter-
faces (desktop alerts), reverse 911, SMS text messaging, commercial radio broad-
cast, cable TV, PDAs, cell phones, digital signage, strobe lights, and paging.
110 Smart Building Systems for Architects, Owners, and Builders