Furuno 9ZWWR2120, Installation Manual

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B. COMMUNICATION NETWORK
Radar needs an internet connection to provide remote maintenance service, main operation, and
transfer of collected observation data.
There are several types of communication network in the world. Only the following types are fast
enough to support proper radar operations.
1) Cable (Broadband Internet Connection): Through the use of a cable modem you can have a
broadband Internet connection that is designed to operate over cable TV lines. Cable Internet
works by using TV channel space for data transmission, with certain channels used for
downstream transmission, and other channels for upstream transmission. Because the coaxial
cable used by cable TV provides much greater bandwidth than telephone lines, a cable modem
can be used to achieve extremely fast access. Cable providers typically implement a cap to limit
capacity and accommodate more customers. Cable speeds range is approx. 512 Kbps to 20
Mbps.
2) Wireless Internet Connections: or wireless broadband is one of the newest Internet connection types.
Instead of using telephone or cable networks for your Internet connection, you use radio frequency
bands. Wireless Internet provides an always-on connection which can be accessed from
anywhere — as long as you geographically within a network coverage area. Wireless access is
still considered to be relatively new, and it may be difficult to find a wireless service provider in
some areas. It is typically more expensive and mainly available in metropolitan areas.
3) T (Tier / Transmission System) -1 Line (Lease Line): A popular leased line option for businesses
connecting to the Internet and for Internet Service Providers (ISPs) connecting to the Internet
backbone. It is a dedicated phone connection supporting data rates of 1.544Mbps. A T-1 line
actually consists of 24 individual channels, each of which supports 64Kbits per second. Each
64Kbit/second channel can be configured to carry voice or data traffic. Most telephone companies
allow you to buy just one or some of these individual channels. This is known as fractional
T-1access. T-1 Lines support speeds of 1.544 Mbps. Fractional T-1 speeds are 64 Kbps per
channel (up to 1.544 Mbps), depending on number of leased channels. T-1 standards is basically
use in ANSI, Northern America. There is a similar type (actually consists of 30 individual channels,
each of which supports 64Kbps (up to 2.048Mbps)) in Europe called E-1 Line.
4) Bonded T-1: Two or more T-1 lines that have been joined (bonded) together to increase bandwidth.
Where a single T-1 provides approximately 1.5Mbps, two bonded T1s provide 3Mbps or 46
channels for voice or data. Two bonded T-1s allow you to use the full bandwidth of 3Mbps where
two individual T-1s can still only use a maximum of 1.5Mbps at one time. To be bonded the T-1
must run into the same router at the end, meaning they must run to the same ISP. Typical Bonded
T-1 (two bonded T-1 lines) speed is around 3 Mbps.
5) T-3 Lines (Dedicated Lease Line): Dedicated phone connections supporting data rates of about 43
to 45 Mbps. It too is a popular leased line option. A T-3 line actually consists of 672 individual
channels, each of which supports 64 Kbps. T-3 lines are used mainly by Internet Service Providers
(ISPs) connecting to the Internet backbone and for the backbone itself. A typical T-3 support
speeds ranging is approx. 43 to 45 Mbps. T-3 is a bigger, faster, more expensive version of T1. It
can get up to 44Mbitps upload and download speeds. It is great for medium/large businesses, as it
provides a good deal of bandwidth. T2, T4, T5 all exist as well, with the higher numbers being
faster, however T1 and T3 are the more common ones. T-3 standards is basically use in ANSI,
Northern America. There is a similar type (16 individual channels (34.368Mbps/480 channel)) in
Europe called E-3 Line.
6) OC3 (Optical Carrier): Short for Optical Carrier, level 3 it is used to specify the speed of fiber optic
networks conforming to the SONET standard. OC3 is typically used as a fiber optic backbone for
large networks with large voice, data, video, and traffic needs. Speeds are 155.52 Mbps, or
roughly the speed of 100 T1 lines.