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ECE's Nortel
Communications Lab @ NCSU
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Captive:-Central
Office & Subscriber Loops
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| A mock-up of a complete telecom system, a "Captive Office;" from POTs
to Set-top Cable MODEMS: encompassing Wireless, Cellular, PCS, Video Phone,
Data Networks, Internet, Intranets, LANs, Internet TV, SDTV, EDTV, HDTV,
etc. |
| Subscriber telephone; pedestal to TW Pair with
repeating coils; C.O. cross-connect "entrance"
(outside plant to inside plant) with line build-out; (Subscriber Line Interface
Circuit--SLIC; CODEC) subscriber Line Pack as part of C.O. Digital
switch (DMS); Digital Switch: Network switching, etc.
Subscriber telephone; pedestal to TW Pair with
repeating coils; to the Subscriber Carrier
(equiv. to T1; Copper/Fiber); Carrier Repeaters; C.O.
Carrier Interface (Outside Plant to Inside Plant) with carrier build-out;
C.O. Digital switch (DMS); Digital Switch: Network switching, etc.
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TEST
EQUIPMENT & DEVELOPMENT SYSTEMS
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| HP
8920/008/011/102 Dual Mode Cellular Mobile Test System
22 complete instruments
TDMA NADC Mobile test for Analog & Digital cellular telephones.
Dual mode cellular adapter with ñ/4DQPSK signal generator
ñ/4DQPSK modulation analyzer,
data source
BER analyzer
Options available:
Spectrum analyzer from
5-kHz to 1-GHz
CCIT weighting filter
Low-level power measurment
Price: used $19,995.00
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Test
Equity http://www.testequity.com/
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| Wireless:
Cellular phone; wireless modem,
Networks:
Dial-Up (Switched), ISDN, Ethernet, Token Ring, T1, FDDI, ATM, Sonet,
Fiber Channel, etc.
Copper: ISDN, ADSL, DSL...
Fiber Optics: FDDI, ISDN WB, Fiber Channel, Sonet, etc.
Satellite Communications:
Broadcast
Bi-directional
Fiber Optics
Set-Top Cable MODEM
Delivery Systems
Delivery Protocols
Data, Entertainment, Multi-media...
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Analog Devices "Analog
Dialogue Magazine"
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Current Release
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Volume
31, Number 2, 1997
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This 24-page issue features an article on precison battery charging, plus
Part 2 of the "DSP101" tutorial series and Part 4 of the tutorials on selecting
mixed-signal components for digital communications systems. Learn how to
handle capacitive loads on op amps in "Ask The Applications Engineer".
New-product news includes a 14-bit, 1.25-to-10-MSPS A/D converter family,
a 200-MHz 16x16 video crosspoint switch IC, and a compact, 480-MFLOPS quad
SHARC DSP, plus 24 New-Product Briefs on converters, amplifiers, and other
ICs for power management, supervisory, communications, temperature, pin
electronics, etc. Currently available in pdf format, soon available
in HTML.
30th Anniversary Reader Bonus
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Ask
The Applications Engineer
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This special issue of Analog Dialogue is offered as a bonus to our
faithful readers and an encouragement to new readers. We have reprinted
here the popular series, entitled "Ask The Applications Engineer", from
its inception in 1988 through Number 23 in 1996.
Editor's Note: In translating "Ask The Applications
Engineer" items from the older issues of Analog Dialogue to the new combined
booklet, on the way to the printer we inadvertently lost a large number
of square-root signs and Greek letters in the hard-copy version. (Errata
sheet)
Prior Releases
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Volume
31, Number 1, 1997
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Learn about Resistors, the Fundamentals of DSP system design, and How to
build a smart analog process-instrument transmitter. Read about 24 new
products and a Controller-board system for evaluating general-purpose converters.
Learn more about selecting mixed-signal components for digital communication
systems (part3).
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Volume
30, Number 4, 1996
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Read about single- and dual-axis micromachined accelerometers; Electromagnetic
compatibility and the CE mark; Advanced digital video encoders; Voltage
regulators for power management; and 12 new products. Learn more about
current-feedback amplifiers (part 2) and Selecting mixed-signal components
for digital communication systems (part 2).
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Volume
30, Number 3, 1996
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Learn to select mixed-signal components for digital communication systems;
DACs optimized for communication Transmit path; Buffered multiplexers
for video applications
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Volume
30, Number 2, 1996
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Learn how DSP and motor-control Chips simplify DSP-based AC motor control
hardware; Discover Industry's first Integrated Wavelet Video Codec; Read
about AD1859, Industry's most functionally complete 16/18-bit system on
a chip.
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Volume
30, Number 1, 1996
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Read About A New DSP for High-Performance/Concurrent Signal Processing,
A Temperature Data Acquisition System, and follow up Part I with Part II
of Designing Single-Supply, Low-Power Systems.
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Volume
29, Number 3, 1995
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Read about Considerations in Designing Low-Power, Single-Supply Systems,
and Review Part 1 of a two-part article on Designing Single-Supply, Low-Power
Systems.
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Volume
29, Number 2, 1995
See how New High-Speed Data-Acquisition ICs are Meeting the Challenges
of High Speed, Learn how to use Histogram Techniques to measure A/D converter
noise, and why Wideband Radios Need Wide Dynamic Range Converters.
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Analog
Devices "Communications Direct Magazine"
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Inside this Issue
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Analog
Devices "DSPatch
Magazine"
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Current Release
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DSPatch
Number 37, Winter 1997
Prior Release
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DSPatch
Number 36, Fall 1996
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DSPatch
Number 35, Spring 1996
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Informative articles on DSP for concurrent processing, as well as our standard
sections on C tips, current software releases, third parties, workshop
schedules, and much more.
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DSPatch
Number 34, Fall, 1995
Articles on new developments in Analog products, current software releases,
third parties, workshop, and conference schedules.
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Analog
Devices Seminars
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| , for reference or for ideas. Every year across the USA and in a variety
of locations in other countries to share the knowledge of experienced engineers,
and accelerate your design process.
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Analog
Devices Whitepapers
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Listed below are high-level overviews that give you general introductions
to Analog products. Below them are detailed technical papers that provide
in-depth descriptions of specific products.
High-Level Overviews
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Texas
Instruments VelociTI™ Architecture and the TMS320C6X DSP
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Analog
Devices, Inc. In Communications
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Quick overviews of each area of communications.
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ASSPs
for Motion Control Applications Use Embedded Digital Signal Processing
Technology
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ASSPs for Motion Control Applications Embed Digital Signal Processing Technology.
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Digital
Signal Processors: Market Growth Drives Segmentation
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Programmable DSP Increasingly Tuned to the Application.
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ADSP-21xx-Based
Application-Specific Standard Products (ASSPs): GSM Cellular Handset Solutions
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GSM Cellular Handsets Solutions Evolve to ASSPs.
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Wireless
Communications and Analog Devices, Inc.
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ADI positioned to be a key player in the wireless market.
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The
Personal Sound System
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Learn about the Signal Computing technology model.
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Continuous
Time Oversampling: Clearing the Way to Multimedia Integration
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Analog Devices' technique vastly simplifies the job of synchronizing disparate
data from multimedia applications.
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Hybrid
Fiber-Coax Technology Overview
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HFC uses existing infrastructure or newly installed networks to expand
technology transfer.
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Universal
Basestation / Wideband Receivers Background Information
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Analog Devices' newer, more efficient radio architecture is response to
fast-changing technology.
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Sound
Blaster Audio -- The Trojan Horse For Motherboard Integration Of DSPs
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Mushrooming multimedia applications call for increased use of Digital Signal
Processing (DSP).
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Signal
Computing Customer/Retail Product/Developers
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Short list of enterprising participants in burgeoning markets.
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Background
Information: DSP Architecture Streamlines High-Level Language Performance
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Analog Device's first fixed-point DSP embodies a new core architecture
that enables faster, high-level language development methodologies
Technical Background Papers
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Design and Test
of a Multi-Processor DSP Multichip Module
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A multi-processor MCM incorporating four ADSP-21060 floating-point DSP
micro-computers was developed. Operating at a clock rate of 40 MHz the
module achieves peak performance of 480 MFLOPs. The general purpose architecture
is adaptable to many types of applications requiring high performance computing.
This paper discusses design and performance issues relating to the module
and touches on testing used to verify functionality.
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Discrete Multitone
(DMT) vs. Carrierless Amplitude/Phase (CAP) Line Codes
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This paper describes why discrete multitone (DMT) modulation is the best
choice for asymmetric digital subscriber lines (ADSL), and why the international
experts and standards bodies chose DMT when they analyzed the matter. In
terms of communications speed, bandwidth efficiency, spectral compatibility,
performance, robustness and power consumption, DMT is a better choice than
alternative single-carrier technologies.
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A Slightly Technical
Introduction To ADSL (Asymmetric Digital Subscriber Line) Technology
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This white paper describes the ADSL technology: how does it achieve 8Mbps
over a normal phone line, what are the difficulties of the channel and
the signal processing techniques that are used to solve them. It also discusses
the line codes (QAM, CAP & DMT) and some implementation aspects of
actually building an ADSL solution.
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Status & Issues
in xDSL
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This white paper gives historical & technological descriptions of the
various DSL formats (DSL, HDSL, HDSL2, ADSL, RADSL, VDSL), and gives a
summary of the current state or controversies within their development.
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Circle Surround®
Whitepaper
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This whitepaper provides a brief background of surround sound matrix systems,
including discussion of some of the more common surround systems, followed
by an explanation of Circle Surround - its general operation, its advantages
over other systems, and recent improvements that have been made.
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Analog Devices
and ADSL
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A Fast Ramp to the Information Superhighway
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Product
Brief: AD20msp910 ADSL Chipset from Analog Devices
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Lowest-Cost, Most Complete Solution for ADSL Modems
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Competitive Analysis:
Analog Devices, Inc. ADSP-2104 vs. Texas Instruments TMS320C203 [ADSP-2104]
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The major market for the ADSP-2104 is price-sensitive applications using
a general-purpose, programmable DSP. In these markets, the nearest competitor
in price is the Texas Instruments TMS320C20x Family.
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Custom
ASIC Solutions for DSP Engineers
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DSP Systems Designers Gain Access to ASIC DSP
Background
Information about Wireless Communications
Detailed technical information about Wireless Communications Technology.
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AD8001
Product Backgrounder
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Flagship of Analog Devices' new high-speed op am portfolio.
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AD1890
and AD1891 SamplePorts™ Background
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AD1890 and AD1891 mark the beginning of a new era in digital audio.
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All-Digital
Wireless Basestation
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New approach simplifies complexity and streamlines technology.
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High
Speed Low Cost ADCs from ADI
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Four ADCs released between December, 1994, and August, 95.
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Analog
Devices' Mixed-Signal Processors Enable a Novel Solution for Secure Communications
LITEF's Secure Voice Module (SVM) uses ADSP-21msp5x Mixed Signal Processor
(MSProcessor™).
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Analog Devices
Analog
Briefings Newsletter
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New
High Density DC-to-DC Converter Features Integral EMI Filtering
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New 28 V-to-5 V converter simplifies complex power supply systems.
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Analog
Devices Responds to the Changing Aerospace Marketplace
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Analog's commercial space-level flows respond to today's needs.
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Multichip
Modules Increase Functionality in Small Places
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Miniaturization saves board space to meet marketplace demand.
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Six
Flavors of MCM Assembly
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Review the different types of MCM assembly.
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New
Products for Mil/Aero Applications
See the new AD822, AD8036, and AD9040 products.
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Glossary
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Delivery Systems
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TDM
FDM |
Time Division Multiplex
Frequency Division Multiplex |
QAM
PSK
FSK
Mark
Space |
QAM Quadrature Amplitude Modulation
PSK Phase Shift Keying
FSK Frequency Shift Keying |
Wireless
Spread Spectrum
CDMA
TDMA
FDMA |
Code Division Multiple Access
Time Division Multiple Access
Frequency Division Multiple Access |
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Copper
Dial-Up (Switched)
Fiber Optics |
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Internet
Intranet |
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| Gateway |
A Gateway is a "Box" that performs protocol
conversions between different types of networks or applications. |
| 100VG-AnyLAN |
A 100 Mbps version of Ethernet (IEEE 802.12 standard) |
| Ethernet |
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| Gigabit Ethernet |
1 Gbps Ethernet --Alternative to ATM |
| Token Ring |
16 Mbps |
ISDN
ISDN (WB) |
Integrated Services Digital Network; 56-kbps/16-kbps
Wide Band ISDN optical fiber @ 600-Mbps |
| ATM |
Asynchronous Transfer Mode |
| ADSL |
Asymetrical Digital Subscriber Line |
T1
T3
D1
FDDI
Sonet
Fiber Channel
ADSL
DSL
Satellite
Broadcast
Bi-directional
Set-Top Cable MODEM
Data
Entertainment
Multi-media |
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Delivery Protocols
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| ATM (Asynchronous
Transfer Mode) A network technology for both LANs and WANs
that supports realtime voice and video as well as data. The topology
uses switches that establish a circuit from input to output port and maintain
that connection for the duration of the transmission. This connection-oriented
technique is similar to the analog telephone system. ATM is defined
in the Broadband ISDN (BISDN) standard.
Cell Switching
ATM works by chopping all traffic into 53-byte cells, or packets.
This fixed-length unit allows very fast switches to be built, because the
processing associated with variable-length packets is eliminated (finding
the end of the frame). The small ATM packet also ensures that voice
and video can be inserted into the stream often enough for realtime transmission.
Quality of Service
The ability to speficy a quality of service is one of ATM's most important
features, allowing voice and video to be transmitted smoothly. Constant
Bit Rate (CBR) guarantees bandwidth for realtime voice. Variable Bit Rate
(VBR) is used for compressed video. Available Bit Rate (ABR) adjusts
bandwidth for bursty LAN traffic. Unspecified Bit Rate (UBR) provides
no guarantee.
Integration with Legacy LANs
Network applications use protocols, such as TCP/IP, IPX, AppleTalk
and DECnet, and there are tens of millions of Ethernet, Token Ring and
FDDI client stations in existence. ATM has to coexist with these
legacy protocols and networks.
LAN Emulation (LANE), defined by the ATM Forum, interconnects
legacy LANs by encapsulating packets into LANE packets and then converting
them into ATM cells. It supports existing protocols without changes
to Ethernet and Token Ring clients, but uses traditional routers for internetworking
between LAN segments. LAN Emulation does not provide ATM quality
of service. See LAN Emulation.
MPOA is an ATM standard that routes legacy protocols while preserving
ATM quality of service. Expected to be finalized in late 1996, Newbridge
Networks has already implemented MPOA in its edge devices (LAN to ATM devices).
See MPOA.
CIF is a recent technique from Cornell University that utilizes
existing Ethernet clients and provides the quality of service associated
with ATM. It carries ATM cells directly within Ethernet frames.
See CIF.
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Summary
ATM is considered the most effective networking technology to meet
future needs, and most large organizations have either installed or have
plans for ATM backbones. However, new technologies emerge all the
time. For example, Gigabit Ethernet may provide an alternative to
ATM. Expected in the 1997 timeframe, it offers high speed and compatibility
with existing Ethernets. Fibre Channel is another high-speed transmission
system that offers gigabit speeds. Although used mostly for peripheral
transfer, when set up in a switched network configuration, Fibre Channel
offers a billion bits between stations. As with everything else in
this fast-moving industry, there are always new approaches on the horizon.
Stay tuned!
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| Gateway A computer that performs
protocol conversion between different types of networks or applications.
A gateway can convert a TCP/IP packet to a NetWare IPX packet and vice
versa, or from AppleTalk to DECnet, from SNA to AppleTalk and so on.
Gateways function at layer 4 and above in the OSI model.
They perform complete conversions from one protocol to another rather than
simply support one protocol from within another, such as IP tunneling.
Sometimes routers can implement gateway functions.
An email, or messaging, gateway converts messages between two
different messaging protocols.
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| 100VG-AnyLAN A
high-speed version of Ethernet, IEEE 802.12 standard. Developed
by HP, it supports Token Ring as well as 10BaseT
networks. It is a shared media LAN like regular Ethernet, but transmits
at 100 Mbps rather than 10 Mbps. It
employs the Demand Priority access method rather than CSMA/CD, which is
used in 10Base and 100BaseT Ethernets.
Demand Priority is suited to videoconferencing, because it allows
realtime voice and video packets to be given a higher priority than data.
In the past, 100VG-AnyLAN has also been called 100BaseVG and Fast Ethernet,
although Fast Ethernet now refers to 100BaseT.
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| [MORE
Info? Go to Nortel]-->
[BACK to TOP] |
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Nortel
(Northern Telecom) Launches Mass-Market High-Speed Internet Solution
ATLANTA-- Nortel
(Northern Telecom) has taken affordable high-speed Internet access one
step closer to reality. Today, Nortel announced Nortel 1-Meg Modem service,
a mass-market, plug-and-play modem-replacement technology that will be
built into its current telephone switching equipment. The service delivers
a secure, ”always up” connection that’s 17 times faster than a 56k modem.
No more dialing in, no more busy signals, no more slow downloads, and you
can use your phone or fax machine while you’re online... |
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1999 2000 2001 2002 Web Author: Glen A. Williamson
webmaster@williamson-labs.com
Suggestions are Solicited, P l e a s e !
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Last
Update: 12/15/99