LAN Technology Scorecard
- Compiled by
- John Wobus, firstname.lastname@example.org
- LAN info
This is a table (i.e., a "scorecard") of various technologies for
implementing Local Area Networks on various media. For explanation of
the acronyms, many of which are mine, see the keys below.
Technology Rate Dist Packet Wiring As Of Standard Products
---------- --------- ---- ------- ------------ ----- ------------ ---------
4Mb Token 4Mbps 570m TokenR4 Type1/Type2 10/94 IEEEdone Out
4Mb Token 4Mbps 260m TokenR4 C3/C4/C5 10/94 IEEEdone Out
4Mb Token 4Mbps ? TokenR4 Fiber 10/94 IEEEdone Out
16Mb Token 16Mbps ? TokenR16 Type1/Type2 10/94 IEEEdone Out
16Mb Token 16Mbps ? TokenR16 Fiber 10/94 IEEEdone Out
16Mb Token 16Mbps 160m TokenR16 C3/C4/C5 10/94 IEEEdone Out
64Mb Token 64Mbps ? TokenR16 ? 2/95 Rumor ?
100Mb Tkn 100Mbps 100m TokenR? C5 9/97 IEEEdiscuss ?
100Mb Tkn 100Mbps 2km TokenR? Multimode 9/97 IEEEdiscuss ?
1Gb Token 1Gbps ? TokenR? Fiber/TP 9/97 IEEEdiscuss ?
LocalTalk 230.4kbps 300m AppleTk C1 12/94 Proprietary Out
ARCNET 2.5Mbps 100f ARCNET RG62 7/94 ANSIdone Out
TCNS 100Mbps 100m ARCNET RG62A/U 7/94 Proprietary Out
TCNS 100Mbps 150m ARCNET Type1 7/94 Proprietary Out
TCNS 100Mbps 900m ARCNET Fiber 7/94 Proprietary Out
TCNS 100Mbps 100m ARCNET 4PC5 7/94 Proprietary ?
ThinWire 10Mbps 185m Ethern ThinWire 12/93 IEEEdone Out
ThickWire 10Mbps 500m Ethern ThickWire 12/93 IEEEdone Out
10BASE-T 10Mbps 100m Ethern 2PC3 11/93 IEEEdone Out
FOIRL 10Mbps 1km Ethern Multimode 12/93 IEEEdone Out
10BASE-FL 10Mbps 2km Ethern Multimode 2/94 IEEEdone Out
10BASE-FB 10Mbps 2km Ethern Multimode 2/94 IEEEdone Out
10BASE-FP 10Mbps 500m Ethern Multimode 2/94 IEEEdone ?
PMD 100Mbps 2km FDDI Multimode 11/93 ANSIdone Out
oldCDDI 100Mbps 100m FDDI UTP 9/94 Propriet/Obs Out
oldTP-FDDI 100Mbps 100m FDDI 2PC5/Type1/2 9/94 Obsel Out
SDDI 100Mbps 100m FDDI STP 12/95 Propriet/Obs Out
SMF-PMD 100Mbps 40km FDDI Singlemode 2/94 ANSIdone Out
LCF-PMD 100Mbps 500m FDDI Multimode 12/95 ANSIdone Out
TP-PMD 100Mbps 100m FDDI 2PC5/Type1/2 12/95 ANSIdone Out
FDDI-II 100Mbps 40km FDDI Sing/Mult/etc 12/95 ANSIalmost Out
old4T+ 100Mbps 100m Ethern 4PC3/4/5 11/93 IEEEstarting Late 93/94
old100B-X 100Mbps 100m Ethern 2PC5/Type1/Fib 1/94 IEEEsubmtd Out
100BASE-TX 100Mbps 100m Ethern 2PC5/Type1 7/95 IEEEdone Out
100BASE-FX 100Mbps 412m Ethern Multimode 7/95 IEEEdone Out
100BASE-T4 100Mbps 100m Ethern 4PC3/4/5 7/95 IEEEdone Mid 95
100BASE-T8 ? ? Ethern 8PC? 9/94 ? ?
100BASE-T2 100Mbps 100m Ethern 2PC3/4/5 7/95 In works Yrs away
100BASE-SX 100Mbps 412m Ethern Multimode 11/97 ?
FD100BS-SX 100Mbps 670m Ethern Multimode 11/97 ?
100VG-AnyL 100Mbps 100m Eth/To 4PC3/4/5 2/96 IEEEdone Out
100VG-AnyL 100Mbps 150m Eth/To 2PC5/Type1 8/95 IEEEprop ?
100VG-AnyL 100Mbps 2km Eth/To Sing/Mult 6/95 IEEEratified Late 94
100VG-AnyL 100MbpsFD ? Eth/To ? 8/95 IEEEprop ?
100VG-AnyL 400Mbps ? Eth/To C5 8/95 IEEEprop ?
1G-AnyLAN 960Mbps 2km Eth/To Fiber 1/96 IEEEdiscuss 97
100VG-AnyL 4Gbps ? Eth/To Fiber 8/95 IEEEprop ?
T100 50Mbps ? Ethern 2PC3 6/94 Proprietary Out
T100 100Mbps ? Ethern 4PC3 6/94 Proprietary Out
WaveBus 100Mbps 2km Ethern Multimode 12/96 Proprietary Out
WaveBus 100Mbps 500m Ethern Multimode 12/96 Proprietary Out
WaveBus 100Mbps 10km Ethern Singlemode 12/96 Proprietary Out
SwEthern 10Mbps 100m Ethern 2PC3 11/93 No change Out
PACE 10Mbps 100m Ethern 2PC3 11/94 Proprietary 95Q1
SwFastE 100Mbps 100m Ethern 2PC5/Type1 9/95 No change Out
FDSE10 10MbpsFD 100m Ethern 2PC3 3/96 IEEEballot ?
FDSE10 10MbpsFD 2km Ethern Multimode 3/96 IEEEballot ?
FDSEold 10MbpsFD 100m Ethern 2PC3 3/96 To be obsel Out
FDSE100 100MbpsFD 100m Ethern 2PC5/Type1 3/96 IEEEballot ?
FDSE100 100MbpsFD 2km Ethern Multimode 3/96 IEEEballot ?
IS-LAN 16Mbps 100m Ethern 2PC3 2/96 IEEEratified Out
1000BASE-X 1Gbps ? Ethern Fiber/C? 6/96 IEEEdraft Late 97
1000BS-TX 1Gbps 100m Ethernx 4PC5 6/98 IEEEdiscuss ?
1000BS-CX 1Gbps 25m Ethernx TW 3/97 IEEEdraft ?
1000BS-SX 1Gbps 100m Ethernx Multimode 3/97 IEEEdraft ?
1000BS-LX 1Gbps 550m Ethernx Multimode50 3/97 IEEEdraft ?
1000BS-LX 1Gbps 300m Ethernx Multimode62.5 3/97 IEEEdraft ?
1000BS-LX 1Gbps 3km Ethernx Singlemode 3/97 IEEEdraft ?
10GENET 10Gbps ? Ethern? ? 3/99 Discussion ?
CoENET .1-1Gbps 100m Ethern 2PC5/Type1 5/96 Proprietary 12/96
TUTE 100Mbps 1500f Ethern 1PC3 12/95 Proprietary Out
SwToken 16Mbps 300m TokenR16 Type1/C4 7/94 No change Out
FDToken 16MbpsFD 300m TokenR16 Type1/C4 2/94 ? Mid 94
SwFDDI 100Mbps 2km FDDI Multimode 12/93 No change Out
FFDT 100MbpsFD 2km FDDI Multimode 11/94 Proprietary Out
FDFDDI 100MbpsFD 2km FDDI Multimode 11/94 Proprietary Out
FDDIFOL 2.4Gbps ? ? Fiber 10/95 Inactive Future?
HIPPI-PH32 800Mbps 25m HIPPI-FP 100Pair 8/94 ANSIdone Out
HIPPI-PH64 1.6Gbps 25m HIPPI-FP 100Pair 8/94 ANSIdone Out
HIPPI-Ser 800Mbps 10km HIPPI-FP Singlemode 3/95 Speced Out
FibreChan 100Mbps 1.5km FibreChn Mult/Cx/TP 8/94 ANSIdone Out?
FibreChan 200Mbps 10km FibreChn Sing/Mult/Cx/TP8/94 ANSIdone Out
FibreChan 400Mbps 10km FibreChn Sing/Mult/Cx 8/94 ANSIdone Out?
FibreChan 800Mbps 10km FibreChn Sing/Mult/Cx 8/94 ANSIdone Out?
FibreChan 1600Mbps ? FibreChn ? 2/95 Speced ?
FibreChan 3200Mbps ? FibreChn ? 2/95 Speced ?
FC-EP 4Gbps? 10km? FibreChn Sing/Mult/Cx 8/94 ANSIproposed Late 94
Myrinet 640Mbps 25m Myrinet Copper 8/94 Proposed Out
STS3cUNI 155Mbps ? Cell Sing/Mult 12/93 AFpublished Out
DS3UNI 45Mbps ? Cell ? 12/93 AFpublished Out
E3UNI ? ? Cell ? 4/94 ? Out
100MbpsUNI 100Mbps ? Cell Multimode 12/93 AFpublished Out
155MbpsUNI 155Mbps 2km Cell Multimode 12/93 AFpublished ?
155MbpsUNI 155Mbps 100m Cell Type1/Type2 12/93 AFpublished ?
155MbpsUNI 155Mbps ? Cell C5 4/94 AFapproved ?
TAXI/140 140Mbps ? Cell Multimode 11/94 Proprietary Out
SONET/OC1 51Mbps ? Cell Sing/Mult 11/93 Done ?
SONET/OC12 622Mbps ? Cell Sing/Copper 4/94 AFproposed ?
SONET/OC48 2.4Gbps ? Cell ? 11/93 Done? ?
SONT/OC192 10Gbps ? Cell ? 9/96 ANSI? ?
ATMT1 1.5Mbps 2Km Cell UTP 10/94 Proprietary Out
ForumT1 1.5Mbps 2Km Cell UTP 10/94 AFapproved Out
LST1 1.5Mbps 2Km Cell UTP 10/94 Proprietary Out
E1 2Mbps ? Cell ? ? ? Out
J2 6Mbps ? Cell ? 3/95 AFadopted ?
ATM25 25Mbps 100m Cell C3/4/5/Type1 2/95 AFselected Out
CIF 10Mbps 100m Cell 2PC3 5/96 AFproposed ?
STS-1/2 25Mbps ? Cell C3 2/95 AFrejected ?
51MbpsUNI 51Mbps 100m Cell C3/4/5/STP 8/94 AFballot ?
TUT51 51Mbps ? Cell C3 1/95 AFproposed 95H1
TUT155 155Mbps 65m Cell C3 8/95 Proprietary Out
CAP64 155Mbps ? Cell C3 1/95 AFproposed ?
ATMFrm100? 100Mbps ? Cell Copper 2/94 AFproposed ?
Fire100 100Mbps 4.5m ? FireSTP 5/97 IEEEdone Out
Fire200 200Mbps ? ? FireSTP 10/96 IEEEdone ?
Fire400 400Mbps ? ? FireSTP 10/96 IEEEdone ?
P1394.2 800Mbps+ ? ? FireSTP 10/96 IEEEsubm ?
P1394a 800Mbps+ ? ? FireSTP 10/96 IEEEsubm ?
Fire1600 1.6Gbps ? ? FireSTP 5/97 ? ?
SerialE ?Gbps ? ? ? 4/96 IEEE? ?
USB 12Mbps ? ? ? 8/96 ? ?
WideBand 800Mbps 100m Ethern 4PC5 1/98 Proprietary Out
WideBand2 3.2Gbps ? Ethern ? 1/98 Proprietery Now
---------- --------- ---- ------- ------------ ----- ------------ ---------
Technology Rate Dist Packet Wiring As Of Standard Products
- Some don't have short names so I had to improvise.
- The raw rate: note that the raw rate of the transmission
media is often not the bottleneck, and in at least one case (HIPPI)
represents a maximum possible raw rate rather than a fixed rate.
- Maximum distance from a hub to a user station through the given
technology. In the case of the various Ethernet technologies, it does
not include transceiver cable (MAU) distance. Sometimes there are
other limits, e.g. the distance limitations imposed by CSMA/CD.
- what type of packets it transmits. Important in determining
whether bridging between this technology and others needs either
encapsulation or translation. Kinds: Cell, Ethernet, FDDI, TokenRing
Cell refers to ATM cells.
- Type of wire or fiber supported.
- "As Of"
- the date of the source of the latest information incorporated
for the line. For example, if someone sends me e-mail during 12/94
saying that a standard was done in 7/94, then I put 12/94 in this
- current state of the standard
- current state of products
- 4Mb Token
- 4 Mbps Token Ring: IEEE 802.5 4 Mbps.
- 16Mb Token
- 16 Mbps Token Ring: IEEE 802.5 16 Mbps. Distances between
hub and station actually depend upon equipment and ring
configuration. One opinion: C3 is really not suitable, 90m maximum
distance is safest for TP, 160m has been seen to work on C5, and for
more 160m, fiber is best.
- 64Mb Token
- 64 Mbps Token Ring: Nothing more than a rumor at this
point. If IBM has considered it, clearly they would consider foregoing
it simply because of the number of alternatives in the works.
- 100Mb Tkn
- 100 Mbps Token Ring: proposal from
Tolly Round Table and IEEE 802.5 Interim Meeting on High Speed Token
Ring , Aug. 26-27, 1997, at which time an agressive schedule is being
proposed for a copper version based on the 100BASE-TX physical standard,
that will complete standardization during Summer 1998.
Efforts toward a fiber version based on 100BASE-FX will follow.
Packet size not yet set but likely to be same as 16Mb Token.
- 1Gb Token
- Efforts toward a version based on the Gigabit Ethernet standards
are planned after the initial 100Mb Tkn stanard.
- Uses low-grade twisted pair (originally coax) as daisy chain,
bus or star. TCP/IP commonly encapsulated in AppleTalk packets over
- ANSI 878.1. Developed by Datapoint. Uses Token Bus access
method. Aside from RG62, also
runs on twisted pair through baluns. The 100ft limit is with the
use of ARCNET Passive hubs. With an active hub, a 2000ft run is
possible, and I've heard 400ft 2PC3 quoted also.
- Proprietary LAN technology developed by Thomas-Conrad as a
drop-in replacement for ARCNET offering 100Mbps. Also uses Token Bus
- ThinWire Ethernet or IEEE 802.3 10BASE2.
- "ThickWire" Ethernet or IEEE 802.3 10BASE5.
- IEEE 802.3 10BASE-T.
- IEEE 802.3 FOIRL: "Fiber Optic Inter-Repeater Link". Note that
the standard is a bit vague on whether this can be used to connect
a station to a repeater.
- IEEE 802.3 10BASE-FL: replacement for FOIRL.
- IEEE 802.3 10BASE-FB: part of the new IEEE 802.3 10BASE-F
spec: "Synchronous Ethernet" which is a special-purpose link for
linking repeaters that allows the limit on segments & repeaters to be
enlarged. Note that it was designed for inter-repeater links though
it can be used to link to end stations and there are applications
where this can be of use.
- IEEE 802.3 10BASE-FP: part of the new IEEE 802.3 10BASE-F
spec: support for a passive star configuration.
- FDDI "Physical Lay Medium Dependent" part. When "PMD" is used by
itself, it usually refers to the usual kind of FDDI physical layer
that uses multimode fiber. Note that FDDI also uses it as a more
generic term, referring to different FDDI PMD's. Operates at 125Mhz
using a 4B/5B NRZI encoding.
- What was formerly known as CDDI: Proprietary technology
developed by Crescendo. FDDI-like technology adapted to unshielded
twisted pair. Efforts to standardize it have yielded TP-PMD. Cisco,
which bought out Crescendo dropped the trademark on 'CDDI', blessing
its use as a common industry term for TP-PMD.
- "Twisted Pair-FDDI": Technology to run FDDI over twisted
pair proposed by 11 companies that have now joined in with TP-PMD.
- "Shielded Distributed Data Interface". Proposal to run FDDI
over shielded twisted pair by IBM and 10 or so other FDDI companies.
Effectively superseded by the ANSI standards now.
- FDDI "Single-Mode Fiber" PMD. Runs further than PMD.
Published as ANSI X3.184-1993 Rev. (4.2, 12/7/92).
- FDDI "Low-Cost Fiber" PMD. Less expensive than PMD.
Published as X3.237-1995, Rev. 2.2.
- FDDI "Twisted Pair Physical Layer Medium". Also often called
CDDI. ANSI specification for FDDI-like service over UTP or STP(Type1
or Type2). Being standardized by ANSI X3T12. Is now at Rev 2.2
(T12/95-022, 1 March 1995) and published as ANSI X3.263.1995.
Operates at 125Mhz using a 4B/5B encoding, but uses MLT-3 encoding (a
three-state encoding) instead of old CDDI & PMD's NRZI encoding to
reduce emissions. The latest changes to TP-PMD were for a "base line
wander problem". Some "TP-PMD" products sold do not incorporate the
latest revisions the specification.
- FDDI II. I've also seen it called isoFDDI. This is not
necessarily an FDDI follow-on and doesn't change the media &
technology so much as the way it is used. It standardizes a
convention for setting aside bandwidth for various applications, by
supporting multiple 6.144Mbps channels. Note that it can use all the
PMD's for FDDI, thus for example can run 100m on 2PC5. A number of
standards comprise FDDI-II (Hybrid Ring Control, Enhanced Media Access
Control, Enhanceed Physical Layer Protocol, Enhanced SMT Common
Services, Enhanced SMT packet Services, Enhanced SMT Isochronous
- 4T+: old name for 100BASE-T4. It may be that some prestandard
equipment was released under the name 4T+.
- 100BASE-X: old name for 100BASE-TX & 100BASE-FX which now
would refer to pre-standard equipment.
- 100Mbps CSMA/CD 802.3/Ethernet-like LAN also known as Fast
Ethernet. There are three flavors: 100BASE-TX, 100BASE-FX, and
100BASE-T4 (see individual descriptions below). Repeaters or hubs
would be necessary to adapt and there will be a media-independent
interface which NICs can support so that an external adaptor
determines which flavor can be attached. Packets are identical to
802.3 packets (with bit-times 1/10 the time), but the nature of
CSMA/CD requires that the overall radius of the net be limited to 1/10
the size of 10Mbps Ethernet. A typical maximal system would be hubs
on a very short backbone (up to 5 meters), the (repeating) hubs
supporting links up to 100 meters. Single-hub networks allow up to
325 meters (e.g. 225 meters of fiber for one link and 100 meters of
twisted pair for any other link). Extension of the net beyond this
would require a switch, router, or bridge. Fiber links employing the
CSMA/CD but with no hubs can run 450 meters, and full-duplex links
(i.e., with CSMA/CD "disabled") can run 2km. It is obvious that
without (at minimum) switches, that this technology will be limited to
connecting a few offices to a server at most. All three have been
defined by IEEE 802.3 in the IEEE P802.3u/D2 Supplement.
- One of the three flavors of 100BASE-T. Basically a
renaming of the twisted-pair variant of 100BASE-X. Borrows the
physical characteristics of FDDI's TP-PMD, but uses Ethernet framing &
CSMA/CD. A Media Independent Interface will allow a single interface
card to use either this or the other flavors of 100BASE-T, just as the
AUI allows a 10Mbps 802.3 controller to use any of its several types.
See also 100BASE-T above. Also in development is a method for NIC and
hub to negotiate between 10BASE-T and 100BASE-T (called Nway) and I'm
guessing this refers to 100BASE-TX. The method consists of extensions
to the 10BASE-T link integrity test pulse sequence with pulses that
signal 100BASE-T capability. This should allow "dual capability" NIC
cards to be installed before a network is brought up to 100Mbps
- One of the three flavers of 100BASE-T. Basically a
renaming of the fiber variant of 100BASE-X. Borrows the physical
characteristics of FDDI's normal fiber PMD, but uses Ethernet framing
& CSMA/CD. Note that the physical media supports distances up to 2km,
but in a CSMA/CD environment (i.e., any 802.3 except full-duplex
links), there is a maximum limit of 412 meters between on the size of
the entire network. A Media Independent Interface will allow a single
interface card to use either this or the other flavors of 100BASE-T,
just as the AUI allows a 10Mbps 802.3 controller to use any of its
several types. See also 100BASE-T above.
- One of the three flavers of 100BASE-T Basically a renaming
of 4T+. Uses 8B6T (three-state: 8 bits encoded into 6 trits) encoding
and 25MHZ clocking, and in addition to the two pairs traditionally
used in the manner of 10BASE-T, also has two pair used in
bidirectional half-duplex fashion. Among other things, this means
that this particular kind of Ethernet cannot be made full duplex
without the use of more pair. A Media Independent Interface will
allow a single interface card to use either this or the other flavors
of 100BASE-T, just as the AUI allows a 10Mbps 802.3 controller to use
any of its several types. I've read on the net that 100BASE-T4 cannot
be used on 4 pairs within a 25 pair C3 cable because there is too much
near end crosstalk, but that it does work in 4-pair cables (i.e. using
all the pairs). See also 100BASE-T above.
- Something I heard mention of once: possibly
mistaken or defunct.
- New initiative in June 1995.
Being worked on by IEEE 802.3y.
- As of 11/97, I heard of the development
of fiber Ethernet operating at 850nm instead of 100BASE-TX's 1300nm.
It uses 4B/5B encoding.
The advantage of such a scheme is that 100BASE-FL operates
at 850nm, so 10/100 autosensing could be developed.
- "Full Duplex 100BASE-SX".
Should be able to reach 100BASE-SX's non-CSMA/CD physical
distance limitation of 670 meters.
- "100VG-AnyLAN" (VG means "Voice Grade"): Originally a
proposal to IEEE 802.3 for a 100Mbps Ethernet-like network, later
relegated to IEEE 802.12. Formerly known as 100BASE-VG. Uses Demand
Priority media access method and when using 4 pair, Quartet
Signalling, which operates at 30Mhz, using a 5B/6B encoding which keeps
emissions low by using only relatively balanced ratios of the two
states. The spec will indicate that the 4-pair version will operate
at 100m on C3 or 150m on C5. Under good conditions, 200m on C3 and
350m on C5 have been accomplished. My impression is that this is over
4 pair using Quartet signalling.
The 2 pair versions of it operate at 120MBaud, using the 5B/6B encoding
to provide 100Mbps.
I've read on the net that unlike
100BASE-T4, the 4-pair version of 100VG-AnyLAN will work on 4 C3 pairs
within a 25-pair cable. I've seen the net radius quoted at 600m for
C3 and 122m for C5. I read that the IEEE "ratified" 100VG-AnyLAN on
June 13, 1995. As of August, 1995, plans have been announced for full
duplex 100VG-AnyLAN as well as 2PCat 5, 400Mbps, and 4Gbps versions.
- 1 Gigabit variation of 100VG-AnyLAN being developed by
the same IEEE committe (802.12). At the time I heard of this,
not all was decided,
including the exact speed at which it will run: I've heard mention of
500Mbps, and have also heard that it would borrow the physical layer
of 800Mbps Fibre Channel. Word as of early 1998, is that work on this
- Proprietary high-speed Ethernet scheme that runs 50Mbps on
2 pair C3 or 100Mbps on 4 pair C3. Developed & sold exclusively
by LAN Performance Labs.
- Proprietary high-speed Ethernet scheme that runs 100Mbps on
multimode or Single Mode fiber.
- Switched Ethernet: really the same as Ethernet as far as
standards go; just the use of Ethernet to attach a switch (i.e.,
multiport bridge) to a client or smaller group of clients. Typically,
10BASE-T would be used to interconnect the switch and the client.
Since "Switch" has become an industry buzzword, things that used to be
called a "Bridge" are now known as switches, especially models with
more than two ports. Current industry jargon uses the term "Store and
Forward Switching" for what used to be called bridging as opposed to
"Cut Through Switching" and vendors of the two types will argue that
one of these methods is superior to the other. Cut Through Switching
means sending the packet on before it is completely received and
implies very low-latency which is good for network services that
alternate packets in each direction, but it transmits runts and
erroneous packets. A modification of cut-through switching delays
transmission for an Ethernet slot time and avoids transmitting runts.
The latency of a Store and Forward switch depends upon the model--it
is something to check on. They do not transmit either runts or
erroneous packets and for doing so, they adhere to the IEEE 802
standard for bridges. The typical cut-through switch is clearly
harder to build than a store-and-forward switch and was done that way
on purpose to increase performance, but many customers feel a store
and forward switch with good latency offers no significant performance
disadvantage. Other factors aside from sheer performance:
spanning-tree algorithm for loop detection; flow-control; Number of
MAC addresses supported per port.
- Priority Access Control Enabled: 3Com's proprietary
technology designed to reduce Ethernet overhead and latency by
making an Ethernet switch and computer "take turns" sending packets,
probably equivalent to a 2-node token bus. In effect, it takes
advantage of the fact that with switched Ethernet, each "true
Ethernet" has just two nodes on it which can cooperate to help
utilization & latency. Plans are to adapt it to 100Mbps Ethernet
also. Requires both special switch and changes to the user's
- Switched Fast Ethernet: can have physical characteristics
of any of the 100BASE-T or 100BASE-F variants.
- 10Mbps Full Duplex Switched Ethernet (FDSE): standard under
consideration by IEEE 802.3x; a variant of Switched Ethernet which
does not use CSMA/CD, but uses slightly-modified network interface
cards to send & receive packets simultaneously. Presumably based on
10BASE-T for most clients, and cannot be based on ThinWire or
ThickWire Ethernet. Since the distance limitations imposed by CSMA/CD
are eliminated, the only problem is how far a line can be driven. The
standard will be independent of speed so it will apply to selected
versions of 100Mbps and future faster versions of 802.3. There have
been proposals to support up to 50km on single mode fiber.
- pre-standard Full Duplex Switched Ethernet (FDSE): while
there are vendors who offer full duplex switched Ethernet now, none
include all the features of the standard in progress (IEEE 802.3x; see
FDSE10), specifically its flow-control features.
- 100Mbps Full Duplex Switched Ethernet (FDSE): part of the
IEEE 802.3x standard. 100BASE-T4 will not be able to support this
while 100BASE-FX and 100BASE-TX will, given suitable electronics.
100BASE-TX remains electrically limited to 100 meters while 100BASE-FX
can run 2km. See also FDSE10.
- IEEE 802.9A, often called Isochronous Ethernet or isoEthernet,
the latter which is a National Semiconductor Trademark). An
adaptation of 10BASE-T to support another 6Mbps of possibly
multiplexed synchronous data along with the 10Mbps CSMA/CD. Proposed
by National Semiconductor. Uses 4B/5B encoding instead of 1B/2B
encoding to carry the larger amount of data. The 6Mbps is divided
into ISDN channels (i.e. 96B+D+E; E for Ethernet) which do not carry
Ethernet-style packets but can carry a data in the formats supported
by ISDN channels. I've also heard of a 96kbps "M for maintenance"
channel. The 6Mbps channel (group of channels) is compatible with ITU
H.320, a specification used for videoconferencing that can use multiple
ISDN-stle B channels. Promoted by incAlliance.
- Gigabit Ethernet. This is being discussed by IEEE
standards-making groups. Both the IEEE 802.3 and IEEE 802.12
committees are interested in the concept and IEEE 802.3z has been
formed to standardize such a thing. Target is a standard approved by
March 1998 with prestandard products coming available the first half
of 1997. Things being discussed include a CSMA/CD version as well as
a full-duplex version; and a physical layer that consists of a
modified Fibre Channel interface (1250 MBaud signalling for 1Gbps data
rate). Stated objectives are 100m for horizontal cabling, 550 meters
for backbone cabling, and 3km for campus cabling. See separate
entries below for the likely physical standards (1000BS-TX,
1000BS-CX, 1000BS-SX, 1000BS-LX).
CSMA/CD imposes a relation between the
minimum length of packet, the speed of the network and the maximum
size of the network and at 1Gbps, the kinds of packets used on 10Mbps
and 100Mbps Ethernet would restrict the size to 50 meters. Plans are
to effectively increase the minimum frame size by holding carrier up
after the smallest packets, thus allowing CSMA/CD to be used up to 200
meters. Another feature is senders' option to catenate small packets
together while sending.
See IEEE 802.3z and IEEE 802.3ab.
The Gigabit Ethernet Alliance has been formed to facilitate its standarization.
- 1000BASE-TX: Gigabit Ethernet over Catagory 5 Twisted Pair.
A separate IEEE committee, 802.3ab, is working out this standard.
The original target for completion was mid to late 1998.
Goal is to support 100 meters over 4 pair of Category 5 UTP, but
it is possible that a finer degree of standardization of cabling
will be necessary, i.e. it may be that not all Category 5 UTP will
be able to handle it.
It uses four pair with a clock rate of 125Mhertz,
using 5 level signaling, to carry 2 bits each clock cycle with some
room left over for forward error correction & clock synchronization.
See IEEE 802.3ab.
Gigabit Ethernet short-wavelength laser over 62.50 or 50 micron
See 1000BASE-X. Uses Fibrechannel parts. Goal is to assure 100 meters minimum.
Tests show 300m on 62.5 micron fiber and 550m on 50 micron fiber.
See IEEE 802.3z.
Gigabit Ethernet long-wavelength laser over single modeo multimode fiber.
The long light wavelength is 1300 nanometers: equipment to use this
is more expensive but can support longer distances.
Goal is to assure 550 meters on multimode fiber or 3 kilometers
on single mode fiber.
Tests show 850m is possible over mutimode.
See IEEE 802.3z.
Gigabit Ethernet short copper connection. See 1000BASE-X.
Goal is to provide interconnections within a room, e.g. between
Goal is 25 meters over Balanced, Shielded Media ("TW Type Cable").
See IEEE 802.3z.
- As yet unnamed 10 Gigabit Ethernet.
As of 3/97, reports are that there are informal talking among the
usual participants of the IEEE 802.3 work groups.
- a proprietary scheme from Cogent to reverse-multiplex
No name yet, but one assumes it will be 1000BASE-something.
a large stream packets over 1-10 Fast Ethernet links, giving
100Mbps to 1Gbps throughput.
- Tut Systems Inc's Long Distance Ethernet Repeater spec.
Uses propritary noise-rejection methods to run Ethernet over
telephone lines at distances to 1500f.
- analog of Switched Ethernet: each client gets a separate
ring that interconnects it with a high-speed packet switch.
- IBM scheme to add switching to token-ring hubs that would
allow full-duplex linking to individual computers using modified
token-ring adaptors. Has the same wiring characteristics as token
- Switched FDDI: really the same as FDDI as far as standards
go: acts like a very fast multiport FDDI bridge. Basically the
DEC GIGAswitch. Note that it can use all the PMD's for FDDI,
thus for example can run 100m on 2PC5 or 40km on SMF.
- FDDI Full Duplex Technology: DEC's proprietary modified FDDI
that runs full duplex instead of "token passing" on their GIGAswitch
FDDI switch and adaptors. They have a patent on their own method of
detecting automatically whether a link is full-duplex, which requires
extensions to SMT, the FDDI ring-management protocol, which they
license to other vendors. Note that it can use all the PMD's for
FDDI, thus for example can run on 100m on 2PC5 or 40km on SMF.
DEC Licenses the technology to multiple companies.
- (for Full Duplex FDDI: I don't know the true name) I heard
once that Cabletron is planning to offer full duplex FDDI but know
nothing about any details or cooperation between vendors. Note that
it can use all the PMD's for FDDI, thus for example can run 100m on
2PC5 or 40k on SMF.
- FDDI Follow On. An idea floated in the ANSI X3T9.5 committee
for a method of multiplexing FDDI and ATM data on fiber at speeds
up to 2.4Gbps.
- ANSI HIPPI with a 32-bit-wide data transfer. Standardized
by ANSI X3T11.
- ANSI HIPPI with a 64-bit-wide data transfer. Standardized
by ANSI X3T11.
- HIPPI-Ser "HIPPI-Serial"
- HIPPI over fiber or coax; either as a
transparent fiber extender for HIPPI-PH32 or HIPPI-PH64, or as a
native host interface. Being standardized by ANSI X3T11.
- Fibre Channel: an ANSI standard for high-speed data
transfer over fiber designed to do what HIPPI can do and more. It can
be made to emulate HIPPI as well as various disk buses (SCSI, IPI,
Block Mux) and can also carry LAN protocols, (IP, etc). Happens to
use the same 8B/10B encoding as some flavors of ATM. Being
standardized by ANSI X3T11 as ANSI X3.230.199x. Note:
I've seen the numbers 266Mbps and 1.062Gbps quoted so I don't
know how those fit into the 100/200/400/800/1600Mbps heirarchy
of speeds which I heard about previously.
Also, I've seen the Baud Rates quoted as 133, 266, 531, and 1062 MBaud.
- Fibre Channel Enhanced Physical Interface: ANSI proposal
for a faster version of Fibre Channel: 4Gbps or 16Gbps.
- Developed by Myricom. Full-duplex 640Mbps channels
connecting hosts and switches. Uses 0.4" shielded, multiconductor
cable (type CL2(?)).
- ATM Forum SONET STS-3c UNI, 155.52Mbps. Also called OC3.
When you see references to 155Mbps ATM running over fiber, it almost
always refers to this though the UNI spec includes another (see
- ATM Forum DS3 UNI, 44.236Mbps, a standard for carrying
ATM cells on a DS3 telecommunications line. It borrows the Physical Layer
Convergence Protocol from IEEE 802.6. Not actually a LAN protocol,
but rather for WANs.
- ATM (Forum?) E3 UNI, 34Mbps, a standard for carrying ATM cells
on an E3 telecommunications line. E3 is the European equivalent to
North American DS3. Unlike the DS3 UNI, the E3 UNI does not borrow
the PLCP from 802.6. Not actually a LAN protocol, but for WANs.
- ATM Forum 100Mbps multimode fiber private UNI. Often
called TAXI. FORE developed this, borrowing optical characteristics &
basic encoding of FDDI, using AMD's "TAXI" chips. When you see the
phrase "TAXI" or "100Mbps ATM", it almost always means this.
- ATM Forum 155Mbps private UNI. In two flavors: multimode
and shielded twisted-pair. The multimode version is incomplatible
with STS3cUNI. This version is for private networks only and
presumably will be less expensive. The multimode fiber version uses
the same 8B/10B encoding as FibreChannel. I heard that a C5 version
has been proposed. When you see the phrase "fiber 155Mbps ATM", it
almost always doesn't mean this, but rather the SONET STS-3c version.
When you see references to 155Mbps ATM over twisted pair, it almost
always means this.
- ATM server/switch specification developed by FORE and often
called 140Mbps TAXI. Like 100MbpsUNI, adapted from FDDI. The only
difference between this and the 100MbpsUNI is that this has the clock
cranked up 40%. FORE no longer manufactures it since the standard
for the similar STS3cUNI has come out, but they support existing
- We refer to a SONET-based ATM variant using fiber.
- ATM Forum SONET/SDH UNI specification with OC3c/STM-1
framing. Variants of the underlying SONET spec use different media:
multimode, single mode (short reach or long reach).
- We refer to a SONET-based ATM variant using fiber.
- We refer to a SONET-based ATM variant using fiber.
- We refer to a SONET-based ATM variant using fiber.
- I don't know the actual name for a T1-based method supported by
some vendors. It borrows the Physical Layer Convergence Protocol from
IEEE 802.6. E1 is also presumably supported similarly. Not actually
a LAN protocol, but for WANs.
- I don't know the actual name for a T1-based ATM Forum UNI.
Rather than DS1, this uses HEC framing as specified in ITU-T
recommendation G804. Not actually a LAN protocol, but for WANs.
- I don't know the actual name for a proprietary method of
supporting ATM through T1 which is sold by Lightstream. Not actually
a LAN protocol but for WANs.
- I don't know the actual name for an E1-based UNI. "E1" is
a telecom term for a 2Mbps T1-like telecom standard used in Europe.
Here we refer to a method of running ATM over it.
- T2-like 6.3Mbps ATM interface. T2 (between T1 and T3) is
not used in the US, but a version of it is widely used in Japan.
Not actually a LAN protocol, but for WANs.
- 25.6Mbps private UNI proposed to ATM Forum by IBM. Borrows
physical characteristics of 16Mb Token Ring (both operate at 32Mhz),
gaining extra capacity by using FDDI's 4B5B encoding (on top of an
NRZI code) in place of Token Ring's differential Manchester encoding.
As of February 1995, it had been selected by the ATM Forum's
PHY Group over STS-1/2.
Note that AVIDIA Systems and Efficient Networks have decided to
market this under the name "25Base-T", which AVIDIA has tradmarked,
in order to stress that it
will run over the same cable as 10BASE-T.
- "Cells in Frames", also called ATM Emulation. A specification
for putting ATM Cells in Ethernet frames. I listed the
characteristics of 10BASE-T, but it could be run over any type of
10Mbps Ethernet as well as Token Ring. Cornell University is the
primary developer. See http://cif.cornell.edu
- 25.9Mbps private UNI proposed by PMC-Sierra, an ATM chip
supplier (I've also seen the term UniPhy-25 applied to it). It is
proposed as an alternative to the IBM proposal. It uses SONET
framing, thus an interface can share more hardware the SONET-based
versions of ATM. Based on the forum's fractional SONET framing
technology. As of February 1995 it was rejected by the ATM Forum's
PHY working group.
- ATM Forum's "Mid-range Physical Layer Specification for
Category 3 Unshielded Twisted-Pair". Uses AT&T's 16-CAP (Carrierless
Amplitude Modulateion, Phase Modulation; a 16 constellation modem-type
modulation scheme) line coding to transmit the signal. The
transmission convergence layer (framing) conforms to the STS-1 SONET
standard. It can run 160m on C5 cable. Also as a option, the
equipment can be made to support longer distances by dropping to 1/2
or 1/4 speed. 1/2 speed uses CAP-4 encoding and 1/4 speed uses CAP-2
- I don't know the actual name for Tut Systems' reported
proprietary 51Mbps over C3 ATM technology. Uses NRZ encoding.
- I don't know the actual name for Tut Systems' reported
proprietary 155Mbps over C3 ATM technology. Also uses NRZ encoding.
I've read statements that seem to suggest this is supposed to be
compatible with the C5 version of the 155MbpsUNI (or actually,
an enlargment of that spec). The problems with running 155Mbps
over C3 include single attenuation and near-end crosstalk. The
TUT155 technology uses Next cancellators to keep crosstalk to a
- CAP-64 based 155.52Mbps Physical Media Dependent layer proposed
to the ATM Forum. CAP-64 (stands for Carrierless Amplitude
Modulation/Phase Modulation with a 64-point constellation) is
analogous to CAP-16 (see 51MbpsUnNI above) etc. It achieves its speed
despite running the cable at no more than 30Mhz and can comply with
FCC Class-A and Class-B radiation requirements.
- I don't know the actual name. ATM Forum UNI for 100Mbps
over some sort of copper cable. I believe it is just 100MbpsUNI
making use of FDDI's TP-PMD rather than the older fiber PMD.
- 100Mbps "FireWire". FireWire is a popular name for
the data interconnection defined as IEEE 1394-1995. It is a serial bus
more or less designed to interconnect computers and I/O devices.
Among the features: isochronous data transfer (which is supposed
to allow multiplexing data with bandwidth guarantees), up to 63
devices on a bus, hot pluggable devices (typical for LANs, but not for
many types of I/O interconnects).
It uses a special cable made up of two sheilded twisted pairs and power
which is used to allow daisychaining through devices that are powered
off, and possibly to provide power some low-power devices.
Signal is sent on one STP as NRZ, with the other being
a strobe signal which transitions only in cases where two successive
bits are the same.
There is interest among vendors of
consumer and professional electronics in the fields of video, audio,
and games. Though it is really conceived as an improvement on
peripheral busses like SCSI, other types of LANs were also started
with such ideas (e.g. FDDI), and it seems that something like this
could become the dominant technology of the "one-room Home LAN".
An effort is also underway to standardize a FireWire bridge
Also, the IEC has approved it as its standard 1883.
- 200Mbps FireWire/IEEE 1394-1995. See Fire100.
- 400Mbps FireWire/IEEE 1394-1995. See Fire100.
- proposed 800Mbps+ version of FireWire/IEEE 1394.
that is not backward-compatible with Fire100, Fire200, and Fire400.
- proposed 800Mbps+ version of FireWire/IEEE 1394
that is backward-compatible with Fire100, Fire200, and Fire400.
- "Serial Express". Serial Express is Intel's name for
the data interconnection defined as IEEE 1394.2. Supports
higher speeds and longer distances than IEEE 1394 (FireWire).
- USB "Universal Serial Bus"
- designed to be an improved technology
for the kind of communication accomplished with a microcomputer's
serial port. Runs at 12Mbps, supports up to 127 devices through
daisy chaining; supports connection and disconnection while the
computers are powered up.
- Proprietary technology from WideBand Corporation
(note that the name of the technology is similar to a common
Raw throughput is 666.7Mbps downstream (which is divided into
two channels) and 333.3Mbps upstream which
is reduced by 20% through use of 8B/10B coding.
Communication is full duplex, using Ethernet-compatible packets.
- Future faster version of WideBand.
- An AppleTalk packet. 5-603 bytes.
- An ARCNET packet. 1-508 bytes (excluding 254-256).
- An ATM 53-byte cell. Note: there are various proposals for
how typical packets will be broken into cells and restored.
- An Ethernet packet: 64-1518 bytes.
- In the case of Gigabit Ethernet, I heard a rumor that the
minimum packet length would be increased.
- Ethernet or Token Ring style packet.
- An FDDI packet: 0-4478 bytes of data (total of 20 to 4495 bytes
- A Fibre Channel packet. 128-2112 bytes.
- Not really a packet: the framing specific to HIPPI.
- A Myrinet packet. Myricom's software allows 8,368 bytes,
the hardware allows much longer.
- A Token Ring packet. Allows longer packets than Ethernet,
among other things. 4-megabit Token Ring allows 4500 byte packets,
16-megabit token ring allows 17800 byte packets.
- ? Pairs (used in designators 2PC3, 4PC3, 2PC5, 1PC3, etc.;
for example, 2PC3 means "2 Pair Catagory 3 Unshielded Twisted Pair")
- HIPPI 100pair cable.
- Coax or Cx
- some sort of coax: don't know which kind
- some sort of copper connection
- Category 1 Unshielded Twisted Pair
- Category 3 Unshielded Twisted Pair
- Category 4 Unshielded Twisted Pair
- Category 5 Unshielded Twisted Pair
- Special FireWire/IEEE 1394 Shielded Twisted-pair cable.
It includes power.
- Multimode fiber.
- Multimode fiber with a 50 micron core.
- Multimode fiber with a 62.5 micron core.
- Screened Twisted Pair: not listed yet, but I might someday hear
about which technologies that can use it
- Shielded Twisted Pair
- Ethernet/IEEE 802.3 Normal "Thick" Coax.
- Ethernet/IEEE 802.3 ThinWire Coax.
- Balanced, Shielded Media, TW Type Cable (twinaxial cable or
twinax: similar to coaxial cable but with two internal conductors).
- IBM Type 1 STP.
- IBM Type 2 STP.
- Unshielded Twisted Pair
(Note: this includes vendors' plans and announced interests as well
as their current products)
- 4Mb Token
- IBM, etc
- 16Mb Token
- IBM, etc
- 64Mb Token
- 100Mb Tkn
- 1Gb Token
- Apple, many vendors
- Thomas-Conrad, Contemporary Control Systems
- DEC, etc
- DEC, Intel, Xerox, etc
- many vendors
- many vendors
- NCR, many vendors
- Chipcom, IBM
- many vendors
- IBM, 3Com, Madge, Network Peripherals, SysKonnect
- SynOptics, National Semiconductor, DEC, Cisco, NPI, 3Com,
SysKonnect, UB Networks, ODS, Cabletron, IBM, Team Advanced Systems,
Alfa, Chipcom, Distributed Systems International, Gambit, Proteon,
Interphase, Memorex, Network Peripherals, NetWorth, Raylan, Rockwell,
Xyplex, Xylan, GEC Plessey (chip), Motorola (MC68840 chip),
- Loral Federal Systems, Distributed Systems International,
AWA Defense Industries (Austrialia)
- Grand Junction
- SynOptics, Intel, Accton, Sun, DEC (DECchip 21140), 3Com,
National Semiconductor, ODS, Cisco, Thomas-Conrad, Plexcom, TI,
Compaq, Grand Junction, Fujitsu, SMC (SMC91C100 chip), Amber, Asante,
Seeq (84C300 chip), LANNET, NetWorth, Apple, Netcom, Cogent,
Asante, Bay, ANT, Olicom, Proteon, Dayna, Farallon, Rockwell,
Kalpana, Interphase, HP, Shomiti, D-Link, Acacia, Adaptec, GigaLabs
- Grand Junction, National Semiconductor, Sun, SynOptics,
David, Intel, DEC, 3Com, Cabletron, Wellfleet, Chipcom, Racal-Datacom,
SMC, NCR, GEC Plessey (chip), NetWorth, NBase, Farallon, Cnet,
Wolfson (chip) (See list for Fast Ethernet Alliance), Lite-On, IBM,
Sonic, RNS, Dayna, PlainTree, Cisco, Transition, XLNT, Linksys, HyNEX,
- SynOptics, Plexcom, Grand Junction, NBase, Focus,
PlainTree, Cisco, Cabletron, Transition
- 3Com, ATT, DEC, SynOptics, Intel, NCR, NetWorth,
Broadcom (BCM5000 chip) (See list for Fast Ethernet Alliance)
- HP, ATT (Regatta 100 chip set), IBM, Proteon, UB Networks,
SMC, ODS, DEC, D-Link, Andrew, Racore, Racal InterLan, Thomas-Conrad,
3Com, Alfa, TI (chips), Compaq, Cisco, D-Link, Ragula, Newbridge,
Compex, Katron, Madge, Wellfleet, Bay, MultiMedia, Plaintree, Chipcom,
Motorola (chips), AMCC (chips), Pericom (chips), PureData, Kalpana,
- ATT, Compac, HP, Motorola, TI
- LAN Performance Labs
- Kalpana, Artel, Alantec, Grand Junction, LANNET, Cabletron,
3Com, SynOptics, Synernetics, Hughes, Calios, SMC, NBase, NetWiz,
IBM, Xedia, HP, Matrox, Plaintree, Chipcom, Amber, Network
Peripherals, Retix, NiceCom (bought by 3Com), Fibronics, Fibermux,
Onet, Agile, Ascom Timeplex, Bytex, OST, Plexcom, Bay, UB,
Xylan, NetWorth, XNET, CrossComm, Allied Telesys, Cisco, NetVantage,
ODS, Lantronix, Whitetree, Xpoint, XNET, Xedia, ANT, Klever,
ORNET(ONET), XLNT, GigaLabs, HyNEX
- NBase, Cabletron, Cisco, FORE, Galileo (GT-48002 chip)
- Cabletron, Kalpana, IBM, 3Com, Compaq, National Semiconductor,
NCR, SEEQ, Texas Instruments, Cogent, HP, ODS, Sun, SynOptics, NBase,
NetWiz, DEC, Hughes, LANNET, Alantec, Grand Junction, AMD, GigaLabs
- SynOptics, Intel, Kalpana, Grand Junction, 3Com, XLNT
- National Semiconductor, Ascom-Timeplex, Apple, IBM, ATT,
Ericsson, Microsoft, Pacific Bell, Siemens/Rolm, Zydacron, 3Com,
Novell, Sun, Dell, Silicon Graphics, Oracle, Networks AB, Luxcom,
Incite/Intecom, Ascom-Nexion, Luxom, Quicknet, Dialogic, Future Labs,
ITT, Incite, MCI, Primary Rate, Teleos, VCON, (See list for
- Sun, 3Com, Compaq, Granite, Amdahl, Cisco, Packet Engines,
NBase, Network Peripherals, Cabletron, Rapid City, Extreme Networks,
Mammoth Networks, Prominet, Alteon, Bay, MMC Networks,
UB, XLNT Designs, FORE, PlainTree, Ancor, GigaLabs, Acacia,
AMCC (chips), Scalable, Xylan, Foundry (was StarRidge), Adaptec,
Essential Communications, XaQti, Acclaim, Berkeley Networks,
Digital, HP, IBM, Intel, Ipsilon, Madge, Neo, YAGO, G2 Networks,
Foundry, Netcom, Network Appliance, Silicon Graphics,
(See list for Gigabit Ethernet Alliance)
- IBM, NetWiz, Ace North Hills, Madge, Chipcom,
Centillion Networks, Bytex, ODS, SMC, SynOptics, Kalpana, 3Com,
NetEdge, Bay, Cisco, NetVantage, Nashoba, Xylan, Connectware,
Olicom, Northern Telecom, UB
- DEC, Centillion Networks, XLNT
- DEC, Distributed Systems International, CMD, CIsco
- Acri, AMP, Ampex, AMCC, Avaika, Broadband Communications
Products, Chi Systems, CNT, Convex, Cray Computer, Cray Research,
Datatape, DEC, E-Mass, E-Systems, Essential Communications, Fujitsu,
Genroco, GES, HP, Honeywell, Hytech, IBM, Intel, Lockheed, Loral
Defense, MasPar, Maximum Strategy, Meiko Scientific, Methode, Myriad
Logic, NEC, NetStar, NSC, Pacific Title Digital, PsiTech, Silicon
Graphics, Siemens, Sony, Sun, Tera, Texas Instruments, Texas Memory
Systems, Thinking Machines, Triplex Systems, TRW, Vertex, Zitel
- Cray, Network Systems, Broadband Communications Products,
- Avaika, Broadband Communications Products, Essential
Communications, NetStar, Tera
- Ancor, HP, IBM, Sun, Western Digital, GENROCO, Emulux, VLSI,
AMP (see FCSI), Interphase, Seagate, Augment, GigaLabs, Jaycor, Finisar,
- ATM (general)
- FORE, Newbridge, GTE, Fujitsu, ATT, Alcatel, General
DataComm, Hughes, LightStream, NEC, NET, Network Systems, Northern
Telecom, ODS, StrataCom, SynOptics, Telematics, TRW, ADC Kentrox,
Cabletron, Cascade, Cisco, DEC, FastComm, Interphase, NetEdge,
Efficient, ZeitNet, First Virtual, Agile, Whitetree, PMC-Sierra
(PM7345 chip), Connectware, Thomas-Conrad, ATML, RADCOM, Tricord,
Astarte, Philips, IBM, Mikroelektronik Anwendungszentrum Hamburg,
Brooktree, National Semiconductor, TI, TransSwitch, Cypress,
Raytheon (chip), Integrated Telecom Technology (chip), Xylan, HP,
Silicon Graphics, Advanced Telecommunications Modules, Trancell,
SysKonnect, 3Com, NiceCom Ltd (bought by 3Com), ZATM, UB Networks,
Swindon Silicon Systems (chips), SMC, LSI Logic (chips), Fibermux,
Grand Junction, Tandem, Centillion, NetWiz, LANNET, CrossComm, AVIDIA,
SNT, Hitachi, HyNEX, Cellware
- FORE, SynOptics, Sun, TI (chip), NetEdge(FiberCom), Hughes, Cisco,
3Com, TransSwitch (chip), Alcatel, ATT, Fujitsu, General DataComm, GTE,
Hughes, LightStream, NEC, NET, Network Systems, Newbridge, Northern
Telecom, Telematics, TRW, DEC, Digital Link, Interphase,
Network Peripherals, Odetics, Xyplex, PMC-Sierra (PM5346 chip), Olicom,
Chipcom, Centillion Networks, RADCOM, AMCC (chip), Cypress (chip),
SysKonnect, Allied Telesys, First Virtual, Bay, CrossComm,
- FORE, Cisco, Wellfleet, NetEdge(FiberCom), 3Com, TranSwitch
(chip), Alcatel, Fujitsu, General DataComm, GTE, Hughes, LightStream,
NEC, NET, Network Systems, Newbridge, Northern Telecom, StrataCom,
SynOptics, Telematics, TRW, ADC Kentrox, Cascade, DEC, Digital Link,
ODS, RADCOM, Brooktree (Chip), PMC (chip), Bay
- TranSwitch (chip), Alcatel, Hughes, LightStream, Network Systems,
Newbridge, Northern Telecom, StrataCom, Telematics, ADC Kentrox, Cisco,
RADCOM, Brooktree (chip), PMC (chip), General DataComm, Bay, FORE
- FORE, SynOptics, AMD (chip), Cisco, IBM, NET, General
DataComm, Alcatel, General DataComm, GTE, LightStream, NEC, Newbridge,
Cabletron, Digital Link, Interphase, NetEdge, Retix, Connectware,
Chipcom, RADCOM, ZATM, Cisco, First Virtual, Bay
- 155MbpsUNI (Multimode)
- 155MbpsUNI (Type1/Type2)
- 155MbpsUNI (C5)
- Micro Linear Corp (chip), SynOptics, Sun,
Network Peripherals, Northern Telecom?, Connectware, Interphase,
Trancell, SysKonnect, GEC Plessey (chip), Wolfson (chip), Bay, Cisco
- FORE, AMD, GTE
- Telco Systems, Cypress (chip)
- Fujitsu, PMC-Sierra (chip), AMCC (chip), TI (chip), FORE,
Hitachi, Maker, Cisco
- ADC/Kentrox, Stratacom, NEC, Telecommunications Techniques,
RADCOM, General Datacom
- StrataCom, Telematics, FastComm, RADCOM, ADC/Kentrox, HyNet,
Digital Link, NEC, General Datacom, Lightstream, Cascade,
Telecommunications Techniques, FORE
- FORE, Cellware
- IBM (including chip), Chipcom, TranSwitch (ALI-25 chip),
National Semiconductor, HP, ATM Limited, Cellware GmbH, Centillion
Networks, Integrated Device Technology (chips), LSI Logic, Madge,
Olicom, Silcom, Whitetree, Fujitsu (chip), First Virtual, Advanced
Telecommunications Modules, Efficient Networks, ODS, Xircom, RADCOM,
Apple, On Demand, Interphase, Adaptec, Rockwell, FORE, Bay, AVIDIA, SNT
- Cornell University (prototype software), Connectware, IBM,
- PMC-Sierra (chip), Cabletron, Cisco, BNR, Cascade, DSC
- ATT, Newbridge, Northern Telecom?, Interphase, Silicon
- Tut, UB Networks
- Silicon Design (chips)
- Firefly, Miro, Radius, TI (chipset), Sony (chip), Skipstone,
Stewart Connector, Molex, Adaptec, Western Digital, IBM (chip), Symbios Logic,
FujiFilm, Sun, Philips, Microsoft, Compaq, Intel, NEC (chip), Fujitsu
- Apple, TI (chip), FujiFilm (chip), IBM, Adaptec, Molex,
Skipstone, Digital VCR Alliance (consortium), Sony, Yamaha
- TI (chip)
- TI (chip)
- Sony, Apple, Sun, Intel.
- Apple, Compaq, HP, IBM, Unisys, Key Tronic, Mitel, Samsung,
various PC companies
- ATM "Asynchronous Transfer Mode"
- a communications protocol that
transmits data in 53-byte cells using switches and various line
transmission technologies operating at different speeds. A lot of
people associate ATM with high speeds, but really it is more of
a framework for networking that is speed independent and the link
that carries ATM data can be fast or slow.
- DXI "Data Exchange Interface"
- ATM Forum term.
- "High Performance Parallel Interface", defined by ANSI X3T11.
- HSSI "High Speed Serial Interface"
- a 52Mbps interface between
routers and DSUs, originally defined by Cisco and T#systems.
It is also an ANSI standard.
- MAN "Metropolitan Area Network".
- Next "Near end crosstalk".
- name for 802.3 method of negotiating between 10BASE-T and
- OC-x "Optical Carrier level x"
- A SONET term for an optically
transmitted SONET signal at some particular speed. The base rate is
51.84Mbps. OC-1 runs at the base rate, OC-3 runs at 3 times the base
rate, etc. Commonly planned rates are OC-1, OC-3 (155.52Mbps), OC-12
(622.08Mbps), and OC-48 (2.488Gbps).
- PLCP "Physical Layer Convergence Protcool".
- PMD "Physical Media Dependent". Term used to describe the layer of
FDDI that determines the actual type of cable, etc. Also used
in conjunction with other technologies, including ATM.
- SMT "Station Management"
- Network management protocol specific to
- SONET "Synchronous Optical Network"
- A set of standard
fiber-optic-based serial standards in North America. ATM runs as a
layer on top of SONET (ATM also runs on top of other technologies).
Developed by Bellcore and standardized by ANSI. Designed for
telephone companies, for long-distance applications, but in the ATM
world, being adapted to LAN uses.
- SDH "Synchronous Digital Hierarchy"
- Similar to SONET, but used outside
North America. Some of the SDH and SONET standards are identical,
in particular, the versions at 155Mbps and above interoperate.
Standardized by the ITU-T. See SONET (above).
- STM "Synchronous Transport Mode"
- an SDH term.
- STS-x "Synchronous Transport Signal level x"
- a SONET term for an
electrically transmitted SONET signal at some particular speed.
Each STS level corresponds to an OC level (see OC-x above).
- ATM Forum term for working group.
- TAXI "Transparent Asynchronous Transmitter-Receiver Interface"
- literally, the name of a chip from AMD originally designed to handle
Multimode FDDI. Also, the popular name of two ATM interfaces
developed by FORE by adapting the FDDI multi-mode physical layer and
the chips AMD produced to support that part of FDDI. The slower of
the two (100Mbps) was adopted by the ATM Forum and the faster of the
two (140Mbps) was not.
- See "ATM25".
- UNI "User to Network Interface"
- ATM Forum term.
(Note: a good resource is
- American National Standards Institute
- ANSI X3
- ANSI group developing standards for information processing.
- ANSI X3T9
- old ANSI group within X3 that was developing standards for
- ANSI X3T9.3 Committee
- old name for ANSI X3T11 when it was part of X3T9.
- ANSI X3T9.5 Committee
- old name for ANSI X3T12 when it was part of X3T9.
- ANSI X3T11 Committee
- ANSI group standardizing HIPPI and Fibre
- ANSI X3T12 Committee
- ANSI group within X3T9 that standarized FDDI,
PMD, SMF-PMD, and is standardizing TP-PMD and LCF-PMD.
- International Electrotechnical Commission:
not a usual standards bodies for LANs, but is involved in some
technologies that are LAN-like.
- Institute of Electrical & Electronic Engineers
- IEEE 802 Group within IEEE that standardizes LAN technologies.
- IEEE 802.3
- Group within IEEE 802 that standardizes CSMA/CD LANs.
- IEEE 802.3 HSSG
- Former(?) group within IEEE 802 that studied the
issue of a Gigabit version.
- IEEE 802.3ab
- Group within IEEE 802.3 to
work on a Category 5 version of Gigabit Ethernet
- IEEE 802.3b
- Group within IEEE 802.3 to work on a Category 3
two-pair version of Fast Ethernet.
- IEEE 802.3z
- Group within IEEE 802.3 to work on a Gigabit version
of Ethernet. Minutes, etc. at:
- IEEE 802.6
- Group within IEEE 802 that standardizes DQDB MANs.
- IEEE 802.9
- Group within IEEE 802 working on IS-LAN.
- IEEE 802.12
- Group within IEEE 802 working on 100VG-AnyLAN.
- International Telecommunications Union (formerly called the CCITT)
- ITU's Telecommunications Standards Sector.
- ASTRAL "Alliance for Strategic Token Ring Advancement and Leadership"
- Consortium of vendors working on new Token Ring technology developments.
- ATM Forum
- Non-profit international industry consortium chartered to
accelerate ATM acceptance & interoperability. Address: The ATM Forum;
303 Vintage Park Drive; Foster City, CA 94404-1138; 1(415)578-6860.
Members include 3Com, 3DO, ADC Kentrox, AMP/ATM Systems, ATM Ltd,
AT&T, SU-System, AWA Networks, Adaptec, Inc., AMD, AdvanceNet, Agile,
Alantec, Alcatel, Allied Telesis, Ameritech, Apple, ascom Timeplex, BT
Labs, Bear-Stearns & Co, Bell Atlantic, Bellcore, BellSouth, Bipolar
Integrated Technology, Boeing, Bosch Telenorma, Broadband
Technologies, Brooktree, Bull SA, CNT, COMSAT, CSELT, Cable &
Wireless, Cablelabs, Cabletron, Centillion, Chipcom, Cisco,
CompuServe, Cray Comm., Cray Research, CrossComm, Cypress, DSC Comm.,
Data Comm. Technology, David Sarnoff, DoD, Digiboard, DEC, Digital
Link, Ericsson, E-Systems, Efficient Networks, Elec. & Telecom.
Research, EXAR, FORE, France Telecom, Fujikura Technology America,
Fujitsu, Furukawa Electric Tech., GPT Ltd., GTE Gov Systems, General
DataComm, General Instrument, Graphics Comm., HP, Hitachi Telecom USA,
Honeywell, Hughes LAN, IBM, IPC Info SYstems, Information Comm Inst
Singapore, Integrated Device Technology, Integrated Telecom, Intel,
Interphase, Joint Interoperability Test Center, KDD, Kalpana, LSI
Logic, LANNET, Larscom, LLL, Lightstream, Loral Data Systems, MCI,
MCNC, MFS, Madge, Microsoft, Mitel, Mitre, Mitsubishi, Motorola,
Multimedia, NEC, NET/ADAPTIVE, NTT, NYNEX, National Inst. of Standards
& Tech, National Semiconductor, NetEdge, Netrix, Network
Communications, Network General, Network Peripherals, Netowrk Systems,
Newbridge, Nokia, Northern Telecom, Novell, OKI, Olicom, OST, PMC
Sierra, Pacific Bell, Philips, Proteon, QPSX, Quality Semiconductor,
Racal-Datacom, Raynet, Raytheon, SGS-Thomson, SITA, Sandia National
Labs, Scientific Atlanta, Siecor, Siemens, Sierra Research &
Technology, Silicon Graphics, Silicon Systems, Sony, Southwestern
Bell, Sprint, SMC, Stratacom, Sumitomo Electric, Summa Four, Sun,
SuperNet, SynOptics, T3plus Neworking, TRW, TTC, Tekelec, Tektronix,
Telco Systems, Telecom Finland, Telecom Italia, Telefonica I&D,
Telematics International, Ltd., Telenex, Telia, Tellabs, Telogy,
Telstra, Texas Instruments, RAD, Thomson-CSF, Toshiba, Transwitch,
Trillium Digital Systems, TriQuint, US WEST, UB, Unisource Business,
Unisis, VLSI Technology, VTT Information Tech, Valor Electronics,
Verilink, Wellfleet Communications, Whitetree Network Technologies,
WilTel, Xerox Parc, Xylan, Zeitnet, Zynrgy Group.
- PHY SWG
- working group within the ATM Forum which deals with the
- Desktop ATM25 Alliance
- Coalition of 25 companies to develop the
ATM25 specification and submit it to the ATM Forum. Members include
IBM, Madge, Centillion Networks, Chipcom, Efficient Networks, First
Virtual, Olicom, ODS, Xircom, Apple, On Demand, Interphase, LSI Logic,
Fujitsu, Transwitch, Advanced Telecommunications Moldules Ltd.,
- Fast Ethernet Alliance (FAE)
- Now disbanded; was group of vendors
working on the three variants of 100BASE-T/100BASE-F. Their stated
reason for disbanding was that whereas the standards process was
initially assisted by having a consortium to do the groundwork for the
IEEE, with the ratification of the standard, the IEEE 802.3 committee
has the process well in hand. Members included: 3Com, Cabletron,
DAVID, DEC, Grand Junction, Intel, LANNET, National Semiconductor,
SEEQ, SMC, Sun, Du Pont, Exar, IMC, JLP, LMC, Microlinear, NEC,
Olympic Technology, Unisys, NetWorth, CNet, Cray, Hughes, Hyundai,
Interphase, Montrose, Network General, Novell, Packet Engines Inc.,
ODS, Asante, Bay (both Synoptics and Wellfleet were members).
- Full Duplex Switched Ethernet Consortium
- Group of vendors that are
working out the details of FDSE. Members include: Cabletron, Compaq,
IBM, Kalpana, National Semiconductor, NCR, SEEQ, and Texas Instruments.
- Fibre Channel Association
- Group of vendors promoting Fibre Channel development, acceptance,
- Fibre Channel Systems Initiative (FCSI)
- Group of vendors
promoting a profile for using Fibre Channel for high-powered
Members include: HP, IBM, Sun.
- HIPPI Networking Forum
- Consortium of vendors (initially 11) to
promote the use of HIPPI. Members include: AMMC, Avaika, Broadband,
E-Systems, Essential, IBM, Loral Defense, Los Alamos National Lab,
Maximum Strategy, Methode, Myriad Logic, NSC, NetStar, PsiTech,
Silicon Graphics, Triplex Systems, TRW, University of Illinois, and
University of Minnesota.
- 100VG-AnyLAN Forum
- Group of vendors trying to accelerate 100VG-AnyLAN
acceptance & interoperability. Charter members include ATT, HP, IBM,
ODS, Proteon, UB, Wellfleet. Address: North Highland,s CA,
Phone number: 1(916)348-0212.
- University of New Hampshire InterOperability Lab
designed to improve the operation of hetrogeneous networks. See
- IncAlliance "Isochronous network communciation alliance"
- Group of
vendors working together to foster and manage the deployment of
isoEthernet. Members include Apple, Ascom-Nexion, AT&T, DataBeam,
Dialogic, Ericsson, Future Labs, IBM, ITT, Incite/Intecom, Luxcom,
MCI, National Semiconductor, Pacific Bell, Primary Rate, Quicknet,
Siemens/Rolm, VCON, Zydacron.
- Digital VCR Alliance
- Group of vendors defining standards for
digital VCRs and camcorders. They are including FireWire interfaces
in the standard.
- Gigabit Ethernet Alliance (GEA)
- Group of vendors working together to help drive the standarization
of Ethernet at 1Gbps data rates. Its 100-plus members include
3Com, Acacia, Ancor,
Apple, Bay, Cabletron, Cisco, Compaq, Cypress Semiconductor, Digital,
D-Link, FORE, Granite, HP, IBM, Intel, Kingston Technology, LANart,
Level One Communications, LSI Logic, Lucent, Madge, MediaWise, NBase,
National Semiconductor, Ornet, Packet Engines, Shiva, Silicon Graphics,
Sun, TI, UB, VLSI Technology XaQti, XLNT Designs, ZNYX, Netcom Systems,
Network General. See
- 1394 Trade Association
- Group of vendors promoting the use of FireWire
a.k.a. IEEE 1394. Membership includes more than 45 companies,
including Apple, Microsoft, Sun, Compaq, and Intel.
- CIF Alliance
- Group of vendors promoting CIF. Members include 3Com,
3M, Agile, Apple, Bay, Bell Atlantic, Brooktree, Cisco, Connectware,
Cornell University, First Virtual,IBM, Madge, Matsushita, NSF,
PMC-Sierra, Stratacom, Sun laboratories, UC Davis, and Whitetree.
(note: virtually all deal with 10BASE-T and older Ethernet styles and
multimode PMD FDDI; Many are members of the ATM Forum, but I don't
have a list of members)
- primary proponent of 4Mb Token, 16Mb Token, SwToken, FDToken,
ATM25, 100Mb Tkn, 1Gb Token;
active in TP-PMD, 100VG-AnyL, SwEthern, FDSE, IS-LAN,
100MbpsUNI, 10BASE-FB, FibreChan, 10BASE-FB, SDDI, HIPPI-PH32,
100BASE-TX; consortiums: Full Duplex Switched Etherent, Fibre Channel
Systems Initiative, 100VG-AnyLAN Forum, ATM Forum, HIPPI Networking
Forum, Gigabit Ethernet Alliance.
- primary proponent of SwFDDI and FFDT; active in SMF-PMD, TP-PMD,
100BASE-TX, 100BASE-T4, 100VG-Anyl, FDSE, STS3cUNI, DS3UNI,
HIPPI-PH32; consortiums: Desktop ATM25 Alliance, ATM Forum.
- active in 100BASE-TX, FDSE, FibreChan, STS3cUNI, C5 155MbpsUNI,
HIPPI-PH32, IS-LAN; consortiums: Fibre Channel Systems Initiative,
ATM Forum, Gigabit Ethernet Alliance.
- primary proponent of LocalTalk; active in IS-LAN, ATM, ATM25,
100BASE-T; consortiums: ATM Forum, Desktop ATM Alliance.
- primary proponent of 100VG-AnyL; active in SwEthern, FDSE,
FibreChan, ATM25, HIPPI-PH32; consortiums: Fiber Channel Systems
Initiative; 100VG-AnyLAN Forum, ATM Forum, Gigabit Ethernet Alliance.
- active in FDSE, 100VG-AnyL, 100BASE-T; consortiums: Full
Duplex Switched Ethernet Consortium, Gigabit Ethernet Alliance.
- active in IS-LAN; consortiums: ATM Forum.
- consortiums: ATM Forum.
Datacomm equipment vendors
3Comprimary proponent of PACE; active in TP-PMD, 100BASE-TX,
100BASE-T4, SwEthern, FDSE, STS3cUNI, DS3UNI, 100VG-AnyL, ATM, 1000BASE-X;
consortiums: ATM Forum, Gigabit Ethernet Alliance.
SynOpticsactive in TP-PMD, 100BASE-TX, 100BASE-FX, 100BASE-T4,
SwEthern, FDSE, FDFastE, STS3cUNI, 100MbpsUNI, 155MbpsUNI;
consortiums: ATM Forum.
Cabletronactive in FDFDDI, TP-PMD, 100BASE-TX, SwEthern,
FDSE, 100MbpsUNI, 1000BASE-X; consortiums: Full Duplex Switched Ethernet
Consortium, ATM Forum, Gigabit Ethernet Alliance.
Ciscoprimary proponent of TP-PMD; active in 100BASE-T, STS3cUNI,
DS3UNI, E3UNI, 100MbpsUNI, 100VG-AnyL, 1000BASE-X; consortiums: ATM Forum.
Wellfleetactive in 100BASE-TX, DS3UNI; consortiums: 100VG-AnyLAN
Forum, ATM Forum, Gigabit Ethernet Alliance.
Bay(see Wellfleet & Synoptics; I'll add items here when I see
explicit news releases about Bay's plans)
active in 1000BASE-X.
Consortiums: Gigabit Ethernet Alliance.
- active in 100BASE-TX, 100BASE-T4, FDFastE; consortiums:
- consortiums: ATM Forum.
- Texas Instruments
- active in 100BASE-T, 100VG-AnyL, STS3cUNI, FDSE;
consortiums: Full Duplex Switched Ethernet Consortium, ATM Forum,
Gigabit Ethernet Alliance.
- The idea spurred three proposals: HP's 100BASE-VG which
doesn't use CSMA/CD, and two CSMA/CD proposals, 4T+ and 100BASE-X.
Some IEEE 802.3 members objected to 802.3 working on a non-CSMA/CD
proposal since "by definition", that group worked on standardizing
CSMA/CD networks. That held up standardization efforts for a while,
but finally a new group 802.12 was formed. All three proposals still
live: 100BASE-VG was expanded to also carry Token-Ring style packets
and renamed 100VG-AnyLAN; 100BASE-X is now called 100BASE-TX, and 4T+
is now called 100BASE-T4.
- Several vendors introduced priorietary methods of running FDDI
over coax & twisted-pair. Crescendo's CDDI was adopted by ANSI with
modifications (of course) as TP-PMD and for a while Crescendo still
used the term CDDI for their standard products, but Cisco (who bought
Crescendo) has dropped the trademark on the term so the industry can
apply it to TP-PMD. Other methods were DEC's methods for running it
over STP and Ethernet ThinNet-style coax, IBM's SDDI for shielded
twisted-pair, and the other UTP competitor: TP-FDDI. SDDI is still
- Proposals date back at least to mid-80s. The technology grew out
of efforts for a new type of switching for both voice and data for
nation-wide networks, and the famous 53-byte cell was originally
proposed to be even smaller by those interested in voice
transmission. Several vendors proposed it as a future LAN technology
and then helped form the ATM Forum to push the technology. The ATM
Forum seems to be a model for a new type of organization: not a
standards organization, but a group of vendors who write "protocol
definition documents" and propose them to the standards bodies, hoping
to get them through without any signficant changes, and remaining
comfortable that they can sell it well enough to create a defacto
standard if need be. An interesting result is that whereas standards
bodies are very open in their standards-defining process, these
organizations are private and do their writing & discussing in
secret. The organizations are typically funded by membership fees,
and few companies other than network equipment vendors are willing to
put up the money.
- ATM25 vs 51MbpsUNI vs STS-1/2
- These are competing standards for the
low end desktop ATM, i.e. UTP. IBM pushed ATM25 and some other
companies pushed a 51Mbps standard. The Forum initially decided
picked the 51Mbps standard, rejecting the other so as to maintain
focus, but in February 1995, after the ATM25 porposal was resubmitted
as well as another competitive proposal (PCM-Sierra's STS-1/2), the
Forum chose to move forward with ATM25.
- Gigabit Ethernet
- Efforts to develop and standardize around mid-90s, borrowing
technology from FibreChannel.
The high speed and Ethernet's small packet size and the use
of CSMA/CD require the distances supported be very small,
and switching is becoming more common,
so there has been some controversy in whether CSMA/CD should
be supported, or whether the packets can be extended or
batched in such a way to support CSMA/CD at a useful distance.
- ATM Forum ATM User-Network Interface Specification Version
3.0 (Prentice Hall, 1993, ISBN: 0-13-225863-3).
- Doug Barr comp.dcom.lans.fddi FAQ (Usenet News FAQ Memo).
- Fast Ethernet Alliance 100Base-X Physical Layer Specification for Fast
Ethernet Version 1.0 (Fast Ethernet Alliance, October 15 1993).
- Fast Ethernet Alliance 100BASE-T 4T+ Physical Layer Specification for
UTP Category 3/4/5 wiring, Section 1.0 Specification Overview
(Fast Ethernet Alliance, December 1993).
- HP Networking White Paper 100VG-AnyLAN: The Natural Evoluation of
Ethernet and Token Ring (Available through HP FIRST: 800-333-1917,
number 7579, 2/1/94).
- HP Networking Backgrounder 100BASE-VG (Available through HP FIRST:
800-333-1917, number 7509).
- HP Networking Application Note 100VG-ANYLAN: A Technical Overview
(Available through HP FIRST: 800-333-1917, number 7567, 2/1/94).
- 100VG-Forum 100VG-Forum A Technical Overview (100VG-Forum Application
Note, 8p., 5/94?). Same as the HP Network Application Note.
- Sidhu, et al Inside AppleTalk, Second Edition (Addison-Wesley, 1990,
- Carl Symborski comp.dcom.cell-relay FAQ: ATM, SMDS, and related
technologies (Usenet News FAQ Memo).
- Greg Watson, Alan Albrecht, Joe Curcio, Daniel Dove, Steven Goody,
John Grinham, Michael P. Spratt, and Patricia A. Thaler "The Demand
Priority MAC Protocol", IEEE Network (Vol. 9 No 1). Paper on
the MAC layer used by 100VG-AnyLAN.
- Grenville J. Armitage & Keith M. Adams "How Inefficient is IP over ATM
Anyway", IEEE Network (Vol. 9 No 1). Paper on the overhead
associated with using ATM to transmit data.
- Customer demand for more speed at a lower price. Full-motion video
is on the way & file servers remain popular.
- How quickly various products are brought to market.
- How quickly various standards stabilize.
- Customers' installed wiring plants. Something that can run on
any line currently running 10BASE-T will have some advantage.
- Customers' installed NICs. A couple of the technologies
require no change.
- Cost of any new equipment or media that is needed.
- Interoperability between existing customer equipment: If customers
need to connect an X server to a Y client, and perhaps necessarily
through a Z piece of networking equipment, they will need a technology
supported by X and Y (and perhaps Z).
- Packet formats: weighing the advantages over simplified bridging
due to using a technology that uses a current packet technology.
- Need for new network software, possibly up to application level.
ATM might become "just another LAN technology" or might revolutionize
everything and take over, eliminating traditional routers. The latter
would require considerable change in a lot of software. Who's writing
such software? Any real efforts to propogate it to as many end
nodes as currently use 10BASE-T?
- Distance limitations: high-speed CSMA/CD is OK for short
distances, but CSMA/CD would have to be "disabled" to run higher
speeds over some distances. In particular, 100mbps CSMA/CD with
Ethernet-sized packets (512 bits minimum) has a radius (maximum
distance) of 250 meters including two repeaters. Without repeaters,
it can be extended to about 400 meters.
- Ability to offer expensive technology only to needed locations
efficiently: customer sites often have a relatively small percentage
of users who need higher-speed technology, and they aren't always
- Potential to integrate LANs and WANs. ATM has been projected
to blur the distinction, making things easier.
- Danger of integrating your LANs too closely with those of other
organizations: do you want, in effect, your competition sharing
your LAN? All the high-schools and colleges throughout the world?
Lots of sites set up extra firewalling before attaching their LAN
to the present Internet.
- Customers' and vendors' desire to pick a long-term winner:
customers listen to vendor announcements and vendors ask customers
what they are likely to buy, both wait a while, and worry about what
to commit to. Predicting the future is never easy, and never
- No translation bridging required
- Uses current NICs
- Supports large packets
- No doubt of success & long future
- Huge market & lots of vendors
- Low cost
- Runs long distances
- Runs over 2PC3
- Runs over WANs as easy as LANs
- No high-cost/high-maintenance routers acting as bottlenecks