DS1 DS3
Digital signal 1 (DS1, also known as a
T1) is a T-carrier signaling scheme devised by Bell Labs. It
is a widely used standard in telecommunications to transmit voice and data
between devices. A DS1 circuit is made up of twenty-four 8-bit channels (a.k.a.
timeslots and DS0's), each channel being a 64 kbit/s DS0 multiplexed
pseudo-circuit. A DS1 is also a full-duplex circuit, meaning you can (in theory)
send 1.536 Mbit/s and receive 1.536 Mbit/s simultaneously. A total of 1.536 Mbit/s
of bandwidth is achieved by sampling each of the twenty-four 8-bit DS0's 8000
times per second. Before the jump in Internet traffic in the mid 1990's, DS1's
were found almost exclusively in the telephone company central office as a means
to transport voice traffic between locations. DS1's have been and still are the
primary way cellular phone carriers connect their central office switches (MSC's)
to the cell sites deployed throughout a city.
Today, companies often use an entire DS1 for Internet traffic, giving you 1.544
million bits per second of connectivity (actually, it's 1.536 Mbit/s; the other
8 kbit/s goes to framing overhead.) However, if you so desire, you can order the
DS1 as a channelized circuit and reserve channels for non-data (i.e., voice)
traffic.
DS1 signals are frequently used to connect equipment within a facility. In this
case, a low-level signal (6 volts peak-to-peak differential) called the DSX1 is
used. DSX refers to a digital signal crossconnect, and it is essentially a patch
panel allowing easy interconnection. When a DS1 leaves the building, it becomes
a T1 and is referred to as a span. The signal is boosted to a higher level and
superimposed on a DC voltage, enabling repeaters in the field to be powered from
the span itself. Repeaters are placed every few thousand feet, to clean up and
strengthen the signal.
DS3 signals are almost
exclusively used within buildings, for interconnections and as an intermediate
step before being muxed onto a SONET circuit. This is because a T3 circuit can
only go about 600 feet between repeaters. When a customer orders a DS3, they
usually get a (much faster) SONET circuit run into the building and a
multiplexer mounted in a big cabinet. The DS3 is delivered in its familiar form,
two coax cables with BNC connectors on the ends.
Data Connect Enterprise
offers a full range of DS1 and DS3 Products from the following manufacturers, and
more
Please contact us
301-924-7400
adtran |
kentrox |
Please contact us 301-924-7400