Specifications

186 Networking and Other Equipment
Datacommunications Tutorial
■ What are networking products?
Networking products consist of
active (powered) communications
devices such as Ethernet switches and
routers, protocol converters and
copper to fiber media converters.
■ How are networking products used?
These products are used to connect
users and devices to a network. Other
uses include extending the distance
of a network and translating
protocols between two different
network types.
■ Where are networking
products used?
Networking products are used
in many voice, video and data
communications applications
including Ethernet networks,
video surveillance, Internet access
applications, and for monitoring and
controlling devices in process and
automation industries.
Datacommunications Terms
Asynchronous Transfer Mode (ATM): Ve r y
high speed network utilizing SONET optical
transmission methods through the public
telecommunications system.
Baseband Transmission: A transmission
method where direct current signals are
placed directly onto the transmission medium
(cable). Ethernet is a baseband network type,
hence, the “Base” in 10Base-T, etc.
Baud Rate: A measure of signal changes per
second. Commonly used to rate the speed of
a modem.
Bridge: A networking component that links
two or more network segments. Bridges are
used to split busy networks into separate, less
congested segments.
Broadband Transmission: A transmission
method where multiple channels are
modulated onto separate carrier frequencies.
The result is multiple communications
channels that occupy specific frequency ranges.
Bus: Also called a "Daisy Chain". A network
topology where each node is connected to
one another in line. A major disadvantage is
that when there is a break in the bus the
entire network goes down.
Client Server: A network architecture where
multiple user workstations (Clients)
communicate with backend servers through
a network. Clients are fully operating systems
that are capable of processing data.
CODEC: An acronym for COder/DECoder. A
device used for converting analog signals to
digital signals. For example, telephone
companies use codecs to convert binary
signals transmitted on their digital networks
to analog signals converted on their analog
networks.
Converter: A device used to convert one
transmission media to another (Ex.
Fiber/Copper Media Converter). Converters
are usually externally powered as they
physically “repeat” or regenerate the signal.
CSMA: (See Basic Ethernet Theory - right).
Ethernet: (See What is Ethernet? - below).
Fiber Distributed Data Interface (FDDI): A
100Mbps fiber optic cabling standard
developed by ANSI. FDDI utilizes a dual
counter rotating ring topology for network
redundancy.
Hub: A network device that receives a signal
from one station and retransmits to all other
connected stations.
Local Area Network (LAN): A network that
remains within one facility (department,
office, building, campus).
MODEM: An acronym for
MOdulator/DEModulator. Modems are data
communications devices that convert digital
signals to analog signals for transmission
over analog public telephone networks.
Network Interface Card (NIC): Network
devices that are installed in computers so that
they can be connected to a network. Ethernet
NICs come in different speeds as well as with
connections to different media types.
Node: A device or station connected to a network.
Peer to Peer: A network architecture where
computers connect directly with other
computers without the need for servers.
Redundancy: Utilizing multiple access
methods so that if one goes down the systems
still operate.
Repeater: A network device that regenerates
the signal to increase a cabling run.
Router: A network device that interconnects
networks. Routers provide traffic control and
filtering functions, they are commonly used
to connect a LAN to the Internet.
Server: A computing device that provides a
service to users on a network (clients). An
example is a file server that stores and
maintains documents for retrieval.
Small Computer System Interface (SCSI): A
peripheral interface that is used to connect
devices to a computer.
Star: The most common network topology
where each node is connected to a central
point. Advantageous because if one part of the
star is lost the network remains intact.
Switch: A switch is a multiport bridge that
segregates different portions of a network for
faster network access (See Basic Ethernet
Theory - right).
Synchronous Optical Network (SONET): A
Bellcore and ANSI standard that defines
transmission of synchronous and time
sensitive (ex: real time video) information.
SONET provides a way for worldwide
carriers to connect equipment.
Token Ring: A networking standard that
utilizes a ring topology. Information is put
onto the ring which is then passed (Token
Passing) to the different stations. The amount
of time that a station possesses the token is
variable which gives some users priority on
the network. Token Ring was standardized by
IEEE under the 802.5 standard.
Transceiver: A device used to change one
media type to another. Transceivers usually
get their power from the NIC.
Wide Area Network (WAN): A network that
spans a greater distance and needs the
involvement of a public carrier.
Shop at L-com.com or call 1-800-343-1455 E-mail: [e-mail] Fax: [phone]
What is Ethernet?
In the early 1980s, Digital Equipment Corporation, Intel and Xerox
developed the Ethernet Local Area Networking format. This
technology was soon accepted by the IEEE Committee, creating the
802.3 standard. This standard dictates the use of CSMA/CD (Carrier
Sense Multiple Access with Collision Detection) as its accessing
scheme. Networks use a variety of NICs (Network Interface Cards),
hubs, transceivers, converters, repeaters & switches, as well as
different types of transmission media for carrying signals.
• Accessing Scheme:CSMA/CD - Carrier sense multiple access
with Collision Detection.
• Speed:10Mbps/100Mbps/1000Mbps (1 GBps).
• Network Architecture:Coax Bus,UTP Star,Fiber Star
10BASE-T
100BASE-T
1000BASE-T
RJ45 JACK
10BASE-FL
100BASE-FX
1000BASE-X
Dual Fiber SC
PLUG
100FX
1000BASE-X
Dual Fiber LC
PLUG
Connectors Commonly Used in Ethernet Environments
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