Glossary Section 0-9
first letter of word:
0-9 A B C D
E F G H I
J K L M N
O P Q R S
T U V W X
that the interface on the equipment can connect to either 10Base-T or at
802 3 specification, similar to Ethernet, using thin coaxial cable that runs at 10 Mbps,
with a maximum distance of 185 meters per segment. Also known as Thin Ethernet or Thinwire
10-Base-5 is also
called Thick Ethernet and ThickWire. Connections are coaxial and operate at
rates up to 10 Mbps.
10Base-F A physical layer
communication specification for 10Mbps, baseband data transmission over a fiber-optic
10Base-T IEEE 802.3
specification, using unshielded twisted-pair cabling and running at 10 Mbps.
100Base-T An Ethernet standard
running at 100 Mbps It uses exactly the same CSMA/CD (Carrier Sense Media Access with
Collision Detection) method as 10-BaseT for sharing the physical network medium between
devices. Also known as Fast Ethernet. Three variants of 100Base-T exist: l00-Base-TX runs
on 2 pairs from a category 5 Unshielded Twisted Pair (UTP) cable; 100Base-T4-runs on 4
pairs from a category 3 or better UTP cable, and 100-Base-FX-runs on optical fiber.
100BaseTX is the
specification that describes how to run 100 Mbps Fast Ethernet over Category 5
Unshielded Twisted Pair. Catagory 5 UTP is the most popular type of cabling used
in LANs today.
10 GbE Ten Gigabit (10,000,000,000 bits (10 billion)) Ethernet
Ethernet standard running at 100 Mbps. In contrast to 100Base-T, 100VG was designed as a
direct replacement for 10BaseT Ethernet that could run on the same category 3, 4, or 5 UTP
cabling infrastructure in the same configurationVG stands for "voice
grade" and refers to the category 3 cable that can be used. It uses a completely
different method from EthernetDemand Priorityto share the network medium
term which refers to the original ARPANET host-to-IMP interface. The specifications for
this were given in BBN report 1822.
1U is equal to 1.75
inches. The "U" increment is a common data communications term to
specify the height in a rack space that will be required.
2B+D The Basic Rate Interface
(BRI) in ISDN A single ISDN circuit divided into two 64 kbps digital channels for voice or
data and one 16 kbps channel for low speed data (up to 9,600 baud) and signaling. 2B+D is
carried on one or two pairs of wires depending on the interface, the same wire pairs that
today bring a single voice circuit into your home or office. See ISDN.
23B+D In ISDN, also known as
the Primary Rate Interface. A circuit with a wide range of frequencies that is divided in
twenty-three 64 kbps paths for carrying voice, data, video, or other information
simultaneously It bears a remarkable similarity to todays T1 link, except that T1
carries 24 voice channels. In ISDN, 23B-i-D gives twenty-three channels and one D channel.
for out of band signaling. However, in T1, signaling is handled in band. See ISDN.
2 Megabit Trunk The basic
digital rate in most of the world, outside of North American and Japan. It consists of 32
- 64 kbps time slots, 0-31. Time slot 0 is reserved for synchronization, and time slot 16
is reserved for signaling.
30 Channel Trunk (E1) A circuit running at 2.048 mbps, and carrying 32 DS0s. Generally,
only 30 of the 32 are available for customer data, the others are reserved for signaling
3/1/0 DACS A digital
access & cross connect system that can divide a DS-3 signal to the
individual DS-1 or DS-0 level.
Internets experimental IPv6 network.
802.x The set
of IEEE standards for the definition of LAN protocols.
802.11a IEEE specifications for a
wireless LAN 5 GHz with data rates to 54 Mbps
802.11b IEEE specifications for a
wireless LAN at 2.4 GHz with data rates to 11 Mbps
802.11g IEEE specifications for a
wireless LAN at 2.4 GHz with data rates to 54 Mbps
802.11n IEEE amendment of the
802.11 standard which defines MIMO operation on the physical lay and
incorporates improvements on the MAC layer.
form of "RFC 822." Refers to the format of Internet style e-mail as defined in
[return to guide] [home page] [specials]
[suggest new words for glossary]