| 100BaseT
- The Ethernet networking standard that
supports a data transmission rate of 100
Mbps and is backward compatible to 10BaseT.
|
| 10BaseT
- The Ethernet networking standard that
supports a data transmission rate of 10
Mbps. |
| 2B1Q
(Two Binary, One Quaternary)
- A line coding technique used in traditional
telecommunications offerings including ISDN.
|
| Access
Network - That portion of a public
switched network that connects access nodes
to individual subscribers. The Access Network
today is predominantly passive twisted pair
copper wiring. |
| Access
Nodes - Points on the edge of the Access
Network that concentrate individual access
lines into a smaller number of feeder lines.
Access Nodes may also perform various forms
of protocol conversion. Typical Access Nodes
are Digital Loop Carrier systems concentrating
individual voice lines to T1 lines, cellular
antenna sites, PBXs, and Optical Network
Units (ONU's). |
| Access
Point - The network hub device for a
wireless network. |
| ADSL
(Asymmetric Digital Subscriber Line)
- Modems attached to twisted pair copper
wiring that transmit from 1.5 Mbps to 9
Mbps downstream (to the sub- scriber) and
from 16 kbps to 800 kbps upstream, depending
on line distance. |
| ADSL
Lite - Nickname for G.lite. DSL based
on the new G.lite standard that supports
1.5 Mbps downstream and 348 upstream.
|
| ANSI
(American National Standards Institute)
- The organization that defines standards
for the United States. |
| APON
(ATM Passive Optical Network) - A
passive optical network running ATM.
|
| ATM
(Asynchronous Transfer Mode) - An
ultra high speed cell based data transmission
protocol which may be run over ADSL.
|
| ATM
25 - ATM Forum defined 25.6Mbit/s cell
based user interface based on IBM token
ring network. |
| ATU-C
and ATU-R (ADSL Transmission Unit,
Central or Remote) - The device at the
end of an ADSL line that stands between
the line and the first item of equipment
in the subscriber premises or telephone
switch. It may be integrated within an access
node. |
| AWG
(American Wire Gauge) - A measure
of the thickness of copper, aluminum and
other wiring in the U.S. and other countries.
|
| Backbone
- A major transmission path used for high-volume
network-to-network connections. |
| Bandwidth
- The amount of data that can flow through
a given communications channel. |
| BDSL
(Same as VSDL B-ISDN Broadband
Integrated Digital Network) - A digital
net- work with ATM switching operating at
data rates in excess of 1.544 or 2.048 Mbps.
ATM enables transport and switching of voice,
data, image, and video over the same infrastructure.
|
| BERT
(Bit Error Rate Test) - A test that
reflects the ratio of error bits to the
total number transmitted. |
| Binary
- A number system based on 2. The binary
to decimal conversions make up the IP addresses
used on any TCP/IP network. |
| B-ISDN
(Broadband Integrated Digital Network)
- A digital network with ATM switching operating
at data rates in excess of 1.544 or 2.048
Mbps. |
| Bit
- The single unit of data used in digital
data communications. |
| Bps
(Bits per second) - The unit of measurement
for data transmission speed over a data
communications link. |
| BRI
(Basic Rate Interface) - This is
an ISDN interface typically used by smaller
sites and customers. |
| Bridge
- A device that connects two networks as
a seamless single network using the same
networking protocol. DSL modems are typically
bridges. |
| Bridge
Tap - An extension to a local loop generally
used to attach a remote user to a central
office switch without having to run a new
pair of wires all the way back. |
| Broadband
- A term used to describe a high-capacity
network that can carry several services
on the same line, such as data, voice, and
video. |
| Byte
- A unit of data consisting of 8 bits.
|
| Cable
Binder - A bundle of local loop wires
that runs along telephone poles or underground
from the CO. |
| CAP
(Carrierless Amplitude) - A version
of QAM in which incoming data modulates
a single carrier that is then transmitted
down a telephone line. |
| CAT5
- Category 5 unshielded twisted-pair wiring
commonly used for 10BaseT and 100BaseT Ethernet
networks. |
| CATV
(Community Access Television) - Also
known as Cable TV. |
| CBR
- Constant Bit Rate. |
| CCITT
- Consultative Committee for International
Telegraph and Telephone. |
| Channel
- A path for digital transmission signals.
|
| CIDR
(Classless Internet Domain Routing)
- CIDR allows IP addresses to be broken
down into smaller subnets than the class
C network, with 256 IP addresses.
|
| Circuit
- A path through a network from source to
destination and back. |
| CLEC
- Competitive Local Exchange Carrier. A
competitor to ILECs offering telecommunications
service. |
| Client
- A program of a device that requests
services from a server. |
| Client/Server
- A style of computer networking that allows
work to be distributed across powerful computers
acting as servers and client computers.
|
| CO
(Central Office) - A circuit switch
that terminates all the local access lines
in a particular geographic serving area;
a physical building where the local switching
equipment is found. |
| CODEC
(Abbreviation for coder/decoder)
- Specifically it converts a voice grade
analog signal to u-law or a-law encoded
samples at an 8KHz sampling rate.
Consists
of a single 16 Kbps data channel plus 2
bearer channels for voice and/or data.
|
| Core
Network - Combination of switching offices
and transmission plant connecting switching
offices together.
In the U.S. local exchange Core Networks
are linked by several competing Interexchange
networks; in the rest of the world (now)
the Core Network extends to national boundaries.
|
| CPE
(Customer Premise Equipment) - A
wide range of customer-premises terminating
equipment which is connected to the local
telecommunications network. This includes
telephones, modems, terminals, routers,
setup boxes, etc. |
| Crosstalk
- The interference induced on a signal on
one line that is caused by the transfer
of energy from a co-located line.
|
| CSA
(Carrier Serving Area) - Area served
by a LEC, RBOC or Telco, often using Digital
Loop Carrier (DLC) technology. |
| CSMA/CD
(Carrier Sense Multiple Access/Collision
Detection) - A network transmission
scheme in which multiple network devices
can transmit across the cable simultaneously.
|
| CSU
- Channel Service Unit. |
| Data
CLEC - A Competitive Local Exchange
Carrier that focuses on IP data communications
links and doesn't provide traditional voice
telecommunications. |
| DCE
- Data Communication (or Circuit-Terminating)
Equipment. |
| Default
Gateway - The address that the IP uses
if the destination address is not on the
local subnet. |
| Demarcation
Point - The point at the customer premises
where the line from the telephone company
meets the premises wiring. |
| DHCP
(Dynamic Host Configuration Protocol)
- A protocol that allows IP addressing information
to be dynamically assigned by a server to
clients on an as-needed basis. |
| Dial-Up
Networking - Used in Windows '95, '98,
NT, and 2000 for making PPP dial-up modem
connections to the internet. |
| DLC
(Digital Loop Carrier) - A telecommunications
structure deployed wherever an ILEC needs
more capacity. |
| DMT
(Discrete Multi-Tone) - An ADSL modulation
technique standardized by the ANSI.
|
| DNS
(Domain Name System) - The name resolution
service for IP addresses that provides the
friendlier text-based addresses for internet
resources. |
| DNS
Service (Domain Name System Service)
- The configuration of user-friendly text
domain names to IP addresses by an ISP using
DNS. |
| Domain
Name - The user-friendly text name used
instead of a numeric IP address for an internet
address. |
| Domain
Name Server - A program that converts
an FQDN into its numeric IP address, and
vice versa. |
| Downstream
- The direction of data flow on a data communications
link that occurs from the network down to
the user. |
| DS0
(Digital Signal 0) - 64 Kbps digital
representation of voice. |
| DS1
(Digital Signal 1) - Twenty four
voice channels packed into a 193 bit frame
and transmitted at 1.544 Mbps. The un- framed
version, or payload, is 192 bits at a rate
of 1.536 Mbps. |
| DS2
(Digital Signal 2) - Four T1 frames
packed into a higher level frame transmitted
at 6.312 Mbps. |
| DSL
(Digital Subscriber Line) - The generic
term that refers to the underlying technology
inherent in all flavors of DSL, such as
ADSL, SDSL, and HDSL. |
| DSL
Bridge - A device that combines one
or more networks into a single seamless
network. |
| DSL
Modem - A common term used for a DSL
bridge. |
| DSLAM
(Digital Subscriber Line Access Multiplexer)
- A device which takes a number of ADSL
subscriber lines and concentrates these
to a single ATM line. |
| DSU
(Data Service Unit) - A digital interface
device that connects end user data communications
equipment to the digital access lines which
provides framing of sub-64Kbps customer
access channels onto higher rate data circuits.
A DSU may be combined with a CSU into a
single device called a CSU/DSU. See Channel
Service Unit/Data Service Unit. |
| DTE
(Data Terminal Equipment) - Typically
the device that transmits data such as a
personal computer or data terminal.
|
| Dynamic
IP Addressing - An IP address is assigned
to the client for the current session or
some other specified amount of time.
|
| E1
- European basic multiplex rate which packs
thirty voice channels into a 256 bit frame
and transmitted at 2.048 Mbps. |
| Echo
Suppressor - An active device used by
the phone company to suppress positive feedback
(singing) on the phone network. |
| EIA
(Electronic Industries Association)
- An organization that provides standards
for the data communications industry.
|
| EMI
- Electromagnetic Induction |
| Ethernet
- A LAN technology that uses CSMA/CD delivery
and can run over different media (cabling).
|
| Ethernet
Address - The unique hardware address
that identifies any Ethernet device.
|
| ETSI
- European Telecommunications Standards
Institute. |
| FCC
(Federal Communications Commission)
- The U.S. government agency for regulating
the telecommunications industry.
|
| FDM
- Frequency Division Multiplexing.
|
| FDQN
(Fully Qualified Domain Name) - The
full name of a host, including all sub domain
and domain names. |
| Feeder
Network That part of a public switched
network which connects access nodes to the
core network. |
| FEXT
(Far End Crosstalk) - The interference
occurring between two signals at the end
of the lines remote from the telephone switch.
|
| Fiber
Optics - A technology in which light
is used to transport large amounts of data
using thin filaments of glass. |
| Firewall
- A security device (hardware or software)
that controls access from the internet to
a local network. |
| Firmware
- Instructions stored in memory that controls
a device, such as a DSL modem or router.
|
| Fractional
T-1 - Any data transmission rate between
56Kbps and 1.54 Mbps (which is the full
T-1 rate). |
| Frame
Relay - A dedicated, public networking
service offered by telecommunication companies
for LAN-to-LAN connections. |
| FTTC
(Fiber to the Curb) - Network where
an optical fiber runs from the telephone
switch to a curbside distribution point
close to the subscriber where it is converted
to copper pair. |
| FTTCab
(Fiber to the Cabinet) - Network
architecture where an optical fiber connects
the telephone switch to a street-side cabinet
where the signal is converted to feed the
subscriber over a twisted copper pair.
|
| FTTH
(Fiber to the Home) - Network where
an optical fiber runs from the telephone
switch to the subscriber's premises.
|
| FTTK
or FTTC (Fiber To the Kerb) -
A Network where an optical fiber runs from
telephone switch to a kerbside distribution
point close to the subscriber where it is
converted to a copper pair. |
| G.dmt
- A standards-based form of ADSL that supports
up to 8 Mbps downstream and 1.54 Mbps upstream.
|
| G.lite
- The new ITU standard that forms the basis
of Universal ADSL, which supports 1.5 Mbps
downstream and 384 upstream. |
| Gateway
- A functional device that allows equipment
with different protocols to communicate
with each other. |
| Hardware
Address - The physical address for the
NIC, which is used by low-level hardware
layers of the network, including DSL bridges.
|
| HDSL
(High-bit-rate Digital Subscriber Line)
- The DSL service widely used for T-1 lines.
HDSL uses four wires (two pairs) instead
of the standard two wires used for other
DSL flavors. Supports symmetrical service
at 1.54 Mbps but doesn't support POTS.
|
| HFC
(Hybrid Fiber Coax) - A system (usually
CATV) where fiber is run to a distribution
point close to the subscriber and then the
signal is converted to run to the subscriber's
premises over coaxial cable. |
| HomePNA
(Home Phone line Networking Alliance)
- The group that created the specifications
for Phone line networking, which uses telephone
wiring as network cabling. |
| HomeRF
(Home Radio Frequency) - A wireless
networking specification that uses the 2.4-GHz
band. |
| Host
- A computer or any device connected to
a TCP/IP network. |
| Hub
- A passive network device that repeats
all data traffic to all ports. A hub is
at the center of a LAN. |
| IDSL
(ISDN Digital Subscriber Line) -
The always-on cousin of dial-up ISDN. IDSL
delivers a symmetric 144 Kbps of bandwidth,
which is 16 Kbps more than the dial-up version
of ISDN. |
| IEC
- Inter-Exchange Carrier |
| IEEE
(Institute of Electrical and Electronics
Engineers) - A worldwide engineering
and standards-making body for the electronics
industry. |
| IETF
(Internet Engineering Task Force)
- The organization that provides the coordination
of standards and specification development
for TCP/IP networking. |
| ILEC
(Incumbent Local Exchange Carrier)
- A new term that emerged from the Telecommunications
Act of 1996 that describes the traditional
local telephone companies. |
| IMAP4
(Internet Message Access Protocol, Version
4) - IMAP4 provides sophisticated client/server
capabilities beyond the features of POP3.
|
| Internet
Address - The unique 32-bit numeric
address used by a host on a TCP/IP network.
|
| Intranet
- A local network that uses TCP/IP and Web
technologies as its networking protocol.
|
| IP
- Internet Protocol. The connectionless
network layer protocol that forms the networking
functions of the TCP/IP suite. |
| IP
address - Internet Protocol Address.
A 32-bit dotted decimal notation used to
represent IP addresses. |
| IPSec
- A virtual private networking protocol
that is part of the IPv6 but is widely used
now in IPv4. |
| IPv4
- The current version of IP addressing based
on 32-bit IP addresses. |
| IPv6
- The next generation of IP addressing based
on 64-bit IP addresses and having a number
of enhancements over IPv4. |
| ISDL
- Uses ISDN transmission technology to deliver
data at 128kbps into an IDSL "modem bank"
connected to a router. |
| ISDN
(Integrated Services Digital Network)
- Gives a user up to 56Kbps of data bandwidth
on a phone line that is also used for voice,
or up to 128 Kbps if the line is only used
for data. |
| ISO
- International Organization for Standards.
|
| ISP
(Internet Service Provider) - An
entity that provides commercial access to
the Internet. These can range in size from
someone operating dial-up access with a
56 kilobit line and several dozens of customers
to providers with multiple pops in multiple
cities and substantial backbones and thousands
or even tens of thousands of customers.
|
| ITU
- International Telecommunications Union.
The ITU is an international body of member
countries that defines recommendations and
standards relating to international telecommunications.
|
| IXC
(Inter-exchange Carrier) - Post-1984
name for long distance phone companies in
the United States. AT&T is the largest,
followed by MCI and Sprint, but several
more small IXCs exist. |
| Kbps
(Kilobits per second) - A measurement
of digital bandwidth where one Kbps equals
one thousand (actually 1024) bits per second.
|
| L2TP
(Layer 2 Tunneling Protocol) - An
IETF protocol used for virtual private networking.
|
| LADC
- Local Area Data Circuit. |
| LADS
- Local Area Data Service. |
| LAN
(Local Area Network) - A data network
that connects computers in an area usually
within the confines of a building or floors
within a building. |
| LEC
(Local Exchange Carrier) - One of
the new U.S. telephone access and service
providers that have grown up with the recent
U.S. deregulation of telecommunications.
|
| Last
Mile - The telephone line between a
local telephone company switching facility
and the customer premises. |
| LATA
(Local Access and Transport Area)
- This was created by the 1984 divestiture
and defines the geographic area over which
the LEC may provide toll calls. |
| Latency
- A measure of the delay between the
sending of a packet at the originating end
of a connection and the reception of that
packet at the destination end. |
| Layer
- In the OSI network reference model, each
layer performs a certain task to move the
data from the sender to the receiver.
|
| Loading
Coil - A metallic, doughnut-shaped device
used on local loops to extend their reach.
|
|
LOCAL LOOP - A pair of wires, moderately
twisted for the entire length between the
telephone company's end office and the user
premises (the common telephone set) form
a loop, so it is referred to as the local
loop. This loop provides a user with access
to the global telecommunications infrastructure
that is installed all over the world. The
local loop has been historically designed
to provide voice grade audio service. The
circuit is powered from the central office
with 48V (open circuit voltage) limited
in current to a value somewhat higher than
20mA. This current is used for signaling
phone access, burning off moisture, breaking
through metallic oxides caused by corrosion,
and powering a carbon microphone. The original
telephone equipment contained no active
electronics. The actual wiring of the local
loop may be considered to be a lossy transmission
line. DSL uses whatever frequencies will
propagate on this line for purposes of digital
data transmission. T1 modulation (alternate
mark inversion) has been doing this for
years. DSL extends the capability by using
modern technology to increase the data rates
and distances spanned.
|
| Loop
Qualification - The process of determining
if a line (or loop) will support a specific
type of DSL transmission at a given rate.
|
| MAC
Address (Media Access Control address)
- The 48-bit defined number built into any
Ethernet device connected to a LAN.
|
| Mbps
(Mega bits per second) - A measurement
of digital bandwidth where one Mbps equals
just over one million bits per second.
|
| MDF
(Main Distribution Frame) - The point
where all local loops are terminated at
a CO. |
| Modulation
- A prescribed method of encoding digital
(or analog) signals on a different waveform
(the carrier signal). Once
encoded, the original signal may be recovered
by an inverse process, demodulation. Modulation
is performed to adapt the signal to a different
frequency range (and medium) than that of
the original signal |
| MPEG
(Motion Picture Experts Group) -
The group that has defined the standards
for compressed video transmission.
|
| MPOE
(Minimum Point of Entry) - The place
where phone lines first enter a customer's
facility. |
| Multiplexer
- Any one of a number of common devices
used to combine multiple telecommunications
circuits into channels. |
| MVL
- Multiple Virtual Lines. A DSL technology
developed by Paradyne. MVL transforms a
single copper loop into multiple virtual
lines to support multiple independent services
over the same line simultaneously.
|
| NAP
(Network Access Provider) - Another
name for the provider of net- worked telephone
and associated services, usually in the
U.S. |
| NAT
(Network Address Translation) - The
translation of an Internet Protocol address
(IP address) used within one network to
a different IP address known within another
network. One network is designated the inside
network and the other is the outside. Typically,
a company maps its local inside network
addresses to one or more global outside
IP addresses and un-maps the global IP addresses
on incoming packets back into local IP addresses.
This helps ensure security since each outgoing
or incoming request must go through a translation
process that also offers the opportunity
to qualify or authenticate the request or
match it to a previous request. NAT also
conserves on the number of global IP addresses
that a company needs and it lets the company
use a single IP address in its communication
with the world. |
| NDIS
(Network Driver Interface Specification)
- Developed by Microsoft to provide a common
set of rules for network adapters to interface
with operating systems. |
| NEBS
- Network Equipment Building Standards.
|
| NEXT
(Near-end Crosstalk) - Interference
between pairs of lines at the telephone
switch end. |
| N-ISDN
(Narrowband ISDN) - Same as ISDN.
|
| NIC
(Network interface card) - The hardware
that forms the interface between the computer
(or other network device) and not only the
data communications network for the LAN
but also the IP connection through a DSL
Ethernet bridge or router. |
| NID
(Network interface device) - A device
that terminates a copper pair from the serving
central office at the user's destination.
|
| NNTP
(Network News Transport Protocol) -
The protocol that governs the transmission
of network news, a threaded messaging system
for posting messages to form newsgroup discussions.
|
| NSP
(Network service provider) -
Any company that provides network services
to subscribers. |
| NTE
(Network Termination Equipment) -
The equipment at the ends of the line.
|
| OC3
(Optical Carrier 3) - An optical
fiber line carrying 155 Mbps; A U.S. designation
generally recognized throughout the telecommunications
community worldwide. |
| ONU
(Optical Network Unit) - A form of
access node that converts optical signals
transmitted via fiber to electrical signals
that can be transmitted via coaxial cable
or twisted pair copper wiring to individual
subscribers. |
| OSI
(Open Systems Interconnection)
- An internationally accepted model of data
communication protocols developed by OSI
and ITU. |
| Packet
- A fixed-or-variable sized unit of information
that can be sent across a packet-switching
network. |
| Packet
CLEC - A Competitive Local Exchange
Carrier that focuses on providing data communication
services instead of voice services.
|
| Packet
Filter - The capability to search a
packet to determine its destination and
then route or block it accordingly.
|
| Packet
Switching - A data transmission method
in which data is transferred by packets,
or blocks of data. |
| Packet-Switched
Network - A network that does not establish
a dedicated path through the network for
the duration of a session but instead transmits
data in units called packets in a connectionless
manner. |
| PBX
- Public Branch Exchange. |
| PC
Card - The credit-card-size adapter
cards used in notebooks. A DSL modem for
a notebook can be a PC Card. |
| PCI
(Peripheral Component Interconnect)
- A specification introduced by Intel that
defines a local bus system that allows up
to ten PCI-compliant expansion cards in
a PC. |
| PCM
- Pulse Code Modulation. |
| Phone
line Network - A networking technology
based on the HomePNA specification that
uses telephone wiring as network cabling.
|
| PnP
(Plug-and-Play) - A system for simplifying
installation of hardware devices on a Microsoft
Windows computer. |
| PON
(Passive Optical Network) - The usual
acronym for a fiber based transmission network
containing no active electronics.
|
| POP
(Point of Presence) - A node of an ISP
containing a DSU-CSU, terminal server and
router and sometimes one or more hosts,
but no network information center or network
operations center. |
| POP3
(Post Office Protocol, Version 3)
- The latest version of the Post Office
Protocol, POP3 provides basic client/server
features for handling email. |
| POTS
(Plain Old Telephone Service) - The
only name recognized around the world for
basic analog telephone service. POTS takes
the lowest 4kHz of bandwidth on twisted
pair wiring. Any service sharing a line
with POTS must either use frequencies above
POTS or convert POTS to digital and interleave
with other data signals. |
| PPP
(Point-to-Point Protocol) - A communications
protocol that allows a computer using TCP/IP
to connect directly to the internet through
a dial-up connection. |
| PPPoA
(Point-to-Point Protocol over Asynchronous
Transfer Mode) - ATM is a high-speed
switching technique used to transmit high
volumes of voice, data, and video traffic.
|
| PPPoE
(Point-to-Point Protocol Ethernet)
- A standard that enables dial-up networking
capabilities over Ethernet. |
| PPTP
(Point-to-Point Tunneling Protocol)
- The VPN client software solution included
with Microsoft Windows 95, 98, NT, and 2000.
|
| PRI
(Primary Rate Interface) - This is
an ISDN interface typically used by larger
users. |
| Protocol
- A set of rules that defines how different
systems interoperate. |
| PSTN
(Public Switched Telephone Network)
- The network that provides global telephone
service. |
| PTT
(Postal, Telegraph and Telephone)
- The generic European name usually used
to refer to state-owned telephone companies.
|
| PUC
(Public Utilities Commission) - A
United States government agency, usually
at the state level, that regulates telecommunication
companies and other utilities. |
| PVC
(Permanent Virtual Circuit) - Connection-oriented
circuit that may be set up by software between
any two nodes of a switched network.
|
| QAM
- Quadrature Amplitude Modulation
|
| QoS
(Quality of Service) - A definition
of a given level of service for voice or
data communication services by a provider.
|
| RADSL
(Rate Adaptive Digital Subscriber Line)
- A version of ADSL where modems test the
line at start up and adapt their operating
speed to the fastest the line can handle.
|
| RBOC
(Regional Bell Operating Company)
- One of the seven U.S. Telephone companies
that resulted from the break up of AT&T.
|
| RJ-11
- A standard modular connector that can
support two pairs of wires (four wires).
RJ-11 connectors are used for most PSTN
CPE (telephones, faxes, and modems).
|
| RJ-45
- A standard modular connector that can
support up to four pairs of wires (eight
wires). RJ-45 connectors are used with category
5 cabling used with 10BaseT or 100BaseT
cabling. |
| Router
- A device that routes data between networks
through IP addressing information contained
in the header of the IP packet. |
| SDSL
(Symmetric Digital Subscriber Line)
- HDSL plus POTS over a single telephone
line. This name has not been adopted by
a standards group, but is being discussed
by ETSI. It is important to distinguish,
however, as SDSL operates over POTS and
would be suitable for symmetric services
to premises of individual customers.
|
| Server
- A host that makes an application or a
service available to other hosts, typically
clients. |
| SMTP
(Simple Mail Transfer Protocol)
- SMTP is the protocol for internet email
that transfers email messages among computers.
|
| SNR
- Signal-to-Noise Ratio. |
| Splitter
- A device used to separate POTS service
from the ADSL data service at a customer's
premises. |
| SSL
(Secure Socket Layer) - SSL version
2 provides security by allowing applications
to encrypt data that goes from a client,
such as web browser, to a matching server.
|
| Static
IP Addressing - An assigned IP address
used to connect to a TCP/IP network. The
IP address stays with the specific host
or network device. |
| STP
(Shielded twisted pair) - A shielded
form of the twisted-pair wiring used for
10BaseT and 100BaseT LANs. |
| STS-1
- SONET basic transmission rate of 51.84
Mbps. |
| Subnet
- A portion of a network. Each subnet within
a network shares a common network address
and is uniquely identified by a sub network
number. |
| Subnet
Mask - A 32-bit number used to separate
the network and host sections of an IP address.
|
| SVC
(Switched Virtual Circuit) - A term
found in frame relay and ATM networking
in which a virtual connection, with variable
end-points, is established through an ATM
network at the time the call is begun.
|
| T1
- A North American standard for communicating
at 1.54 Mbps. A T-1 line has the capacity
for 24 voice and data channels at 64 Kbps
each. |
| T3
- A North American standard for communicating
at speeds of 44 Mbps. A T-3 line has 672
channels for voice and data at 64 Kbps each.
|
| TCP
(Transmission Control Protocol)
- One of two principal components of the
TCP/IP protocol suite. TCP puts data into
packets and provides packet delivery across
the network, ensuring that packets are not
lost in transmission and arrive in order.
|
| TCP/IP
(Transmission Control Protocol/Internet
Protocol) - TCP/IP is the suite of protocols
that define the basis of the internet.
|
| TCP/IP
stack - The software that allows a computer
to communicate through TCP/IP. Stack refers
to the fact that five layers of protocols
operate on a TCP/IP network. |
| TDM
- Time Division Multiplexing. |
| Telco
(Telephone Company) - Generic name
for telephone companies throughout the world
which encompasses RBOCs, LECs, and PTTs.
|
| Telnet
- A terminal-emulation protocol that allows
you to access computers and network devices
through TCP/IP. |
| TPON
(Telephony over Passive Optical Network)
- Telephony using a PON as all or part of
the transmission system between telephone
switch and subscriber. |
| Twisted
Pair - A cable comprised of pairs of
wires twisted around each other to help
cancel out interference. |
| UART
(Universal Asynchronous Receiver/Transceiver)
- The older serial port architecture for
data communications that is limited to 115-Kbps
capacity. |
| UBR
- Unspecified Bit Rate. |
| UDSL
- Unidirectional HDSL as proposed by one
company in Europe without much sign of interest
from anyone else. |
| USB
(Universal Serial Bus) - A new data
communications port installed on most newer
PCs to replace the UART serial port.
|
| UTP
(Unshielded twisted pair) - Cabling
used for 10BaseT and 100BaseT LANs. UTP
consists of pairs of copper wires twisted
around each other and covered by plastic
insulation. |
| VaDSL
- Very high speed ADSL. Same as VDSL.
|
| VBR
- Variable Bit Rate. |
| VDSL
(Very high bit-rate Digital Subscriber
Line) - Modem for twisted pair access
operating at data rates from 12.9 to 52.8
Mbps with corresponding maximum reach ranging
from 4500 to 1000 feet of 24-gauge twisted
pair. |
| VoDSL
(Voice over DSL) - A hybrid voice
communication system that enables digital
voice communications over a DSL network
and then passes the voice to PSTN.
|
| VoIP
(Voice over IP) - Forms the basis of
PC-to-PC voice communications over the internet.
|
| VPN
(Virtual Private Network) - A way
that private data can safely pass over a
public network, such as the internet. The
data traveling between the two hosts is
encrypted for privacy, and other security
features are included to provide a secure
direct connection over the internet.
|
| WAN
(Wide Area Network) - A data network
typically extending a LAN outside a building
over a data communications link to another
network in another location. |
| Web
Hosting - A service performed by an
ISP or a web hosting service that operates
all the web server infrastructure for you.
|
| xDSL
- A generic term used to refer to the entire
family of DSL technologies. |