Difference between revisions of "Ethernet transceiver"

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(H4000 Ethernet Transceiver (Thickwire): Comment on "Heartbeat" added.)
(Transceiver Cables: Changed "XDI" to "DIX")
 
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An [[Ethernet]] Transceiver connects one of the following Ethernet cable types:
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An '''Ethernet transceiver''' performs the [[analog]] functions necessary to connect one of the following [[Ethernet]] cable types:
* [[Thickwire]] Coaxial
 
* [[Thinwire]] Coaxial
 
* [[Twisted Pair]]
 
* [[Fibre Optic]] (different types)
 
to an Ethernet interface using a Tranceicver cable.
 
  
Most modern standard Ethernet interfaces have got the Transceiver included in the network interface module (resp. interface chip), so that neither separate Tranceiver nor Transceiver cable are needed.
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* [[Thickwire]] [[coaxial cable]]
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* [[Thinwire]] coaxial cable
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* [[Twisted pair]]
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* [[Fiber optic]] (different types)
  
A lot of recent high-speed Ethernet interfaces (1 GB/s and above) and [[Network Switches|Switches]] have Transceivers again. They enable to flexibly adapt to different network media, e.g. different types of Fibre Optic cables.
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to an [[network interface]]; the connection from the interface to the transceiver uses a transceiver cable.
 +
 
 +
Most modern standard Ethernet interfaces have the transceiver included in the network interface module (resp. interface chip), so that neither separate transceiver nor transceiver cable are needed.
 +
 
 +
Many recent high-speed Ethernet interfaces (1 GB/s and above) and [[Network switches|switches]] have transceivers again; that enables them to flexibly adapt to different network media, e.g. different types of fiber optical cables.
  
 
<Picture of a recent Transceiver module>
 
<Picture of a recent Transceiver module>
  
 
==Transceiver Cables==
 
==Transceiver Cables==
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[[File:AUI_DROP.jpg|300px|thumb|left|Transceiver Cable, thin "Office Type"]]
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The cable from the transceiver to the network interface is a standard in the [[DIX]] Ethernet specification; this allows transceivers, cables and network interfaces from multiple manufacturers to be interconnected.
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<br clear=all>
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==IEEE 802.3 Standard Naming Conventions==
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The [[IEEE 802.3]] Ethernet Standard named:
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* the Ethernet Transceiver '''MAU''' (for: '''Media Access Unit'''), and
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* the Ethernet Transceiver Interface '''AUI''' (for: '''Attachment Unit Interface''').
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The Transceiver cable was thus named '''AUI cable'''.
  
 
==Ethernet Transceiver Functions==
 
==Ethernet Transceiver Functions==
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* Maintains low loading/high impedance on the coaxial cable,
 
* Maintains low loading/high impedance on the coaxial cable,
 
* Provides continuous data loopback (i.e., the receiver portion of the transceiver is always active; thus, the message being transmitted is coupled back on the transceiver cable),
 
* Provides continuous data loopback (i.e., the receiver portion of the transceiver is always active; thus, the message being transmitted is coupled back on the transceiver cable),
* Provides self test of the collision detection circuitry at the end of each transmission,
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* Provides self-test of the collision detection circuitry at the end of each transmission,
 
* Contains protective circuitry which ensures that network integrity will be maintained in the event of a faulty transceiver, controller, or repeater.
 
* Contains protective circuitry which ensures that network integrity will be maintained in the event of a faulty transceiver, controller, or repeater.
  
==DEC Ethernet Transceiver Models==
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==See also==
 
 
=== H4000 Ethernet Transceiver (Thickwire) ===
 
Year of introduction: 1982
 
 
 
You cannot disabled the '''[[Ethernet Heartbeat|Heartbeat]]''' feature of the standard H4000 Ethernet Transceiver, there was a special version (H4000-BA) without Heartbeat available in case you need that.
 
 
 
====H4000 with Inclusive Tap====
 
[[File:H4000_with_Inclusive_Tap.png|400px|thumb|left|H4000 with Inclusive Tap]]
 
 
 
The H4000 Ethernet Transceiver with Inclusive Tap was the very first [[Ethernet]] Transceiver from DEC.
 
 
 
It has got two drawbacks:
 
* If the tap gets damaged, the whole unit is inoperable and cannot be repaired.
 
* It is very inconvenient to mount the unit to a Thickwire segment difficult to access, e.g. located in a ceiling plenum.
 
 
 
<br clear=all>
 
 
 
====H4000 with Removable Tap====
 
The H4000 Ethernet Transceiver with Removable Tap is an improved version of the model with a fixed tap.
 
 
 
You can tap the cable using the removable tapping unit (which is muchh smaller and lighter than the complete unit) and attach the rest of the unit when the tapping is done.
 
 
 
If the tap gets damaged, you can use a replacement one.
 
 
<Picture of an H4000 with Removable Tap>
 
 
 
=== H4005 Ethernet Transceiver (Thickwire) ===
 
Year of introduction: 1988?
 
 
 
<Picture of an H4005>
 
 
 
=== DESTA Thinwire Ethernet Station Adapter ===
 
Year of introduction: 1986
 
 
 
====Early DESTA====
 
The early DESTA (REV A) is a H4005 with a modified top assembly carrying a female BNC socket.
 
 
 
You can replace the BNC top assembly with that of an H4005 and thus use the early DESTA with Thickwire Ethernet.
 
 
 
On the other hand you can use the top assembly of an early DESTA to use an H4005 for Thinwire Ethernet.
 
 
 
<Picture of an early DESTA>
 
 
 
====Late DESTA====
 
The late DESTA (REV B) is housed in a slightly smaller box and the BNC socket is fixed.
 
 
 
<Picture of a late DESTA>
 
 
 
=== H3350 Twisted Pair Transceiver ===
 
Year of introduction: ?
 
 
 
<Picture of an H3350 Twisted Pair Transceiver>
 
  
=== DECXM Thinwire Transceiver ===
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* [[DEC Ethernet Transceivers]]
Year of introduction: ?
 
  
<Picture of a DECXM Thinwire Transceiver>
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==External links==
  
=== DETPM 10BaseT Transceiver ===
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* [https://www.computerhistory.org/collections/catalog/X124.82E Experimental Ethernet transceiver] - at the [[Computer History Museum|CHM]]; includes a clamped-on vampire tap housing
Year of introduction: ?
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* [http://www.bitsavers.org/pdf/xerox/alto/ethernet/Ethernet_Transceiver_Electrical_Characteristics.pdf Ethernet Transceiver Electrical Characteristics] - complete Experimental Ethernet transceiver specification, including engineering drawings
  
<Picture of a DETPM 10BaseT Transceiver>
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[[Category: Networking]]

Latest revision as of 22:08, 17 August 2022

An Ethernet transceiver performs the analog functions necessary to connect one of the following Ethernet cable types:

to an network interface; the connection from the interface to the transceiver uses a transceiver cable.

Most modern standard Ethernet interfaces have the transceiver included in the network interface module (resp. interface chip), so that neither separate transceiver nor transceiver cable are needed.

Many recent high-speed Ethernet interfaces (1 GB/s and above) and switches have transceivers again; that enables them to flexibly adapt to different network media, e.g. different types of fiber optical cables.

<Picture of a recent Transceiver module>

Transceiver Cables

Transceiver Cable, thin "Office Type"

The cable from the transceiver to the network interface is a standard in the DIX Ethernet specification; this allows transceivers, cables and network interfaces from multiple manufacturers to be interconnected.


IEEE 802.3 Standard Naming Conventions

The IEEE 802.3 Ethernet Standard named:

  • the Ethernet Transceiver MAU (for: Media Access Unit), and
  • the Ethernet Transceiver Interface AUI (for: Attachment Unit Interface).

The Transceiver cable was thus named AUI cable.

Ethernet Transceiver Functions

From "EK-H4000-TM-PRE H4000 Ethernet Transceiver Technical Manual", chapter 1.2.2 "Transceiver Functional Description":

The transceiver performs the following functions:

  • Transmit: Responds to the signals input from the transceiver cable and transmits the signals on the coaxial cable.
  • Receive: Responds to signals transmitted on the coaxial cable and couples the received signals to the transceiver cable.
  • Collision Detect: Monitors the signals transmitted on the coaxial cable and, if a collision occurs, signals appropriately on the transceiver cable.

Additionally, the transceiver does the following:

  • Maintains electrical isolation between the coaxial cable and the transceiver cable,
  • Maintains low loading/high impedance on the coaxial cable,
  • Provides continuous data loopback (i.e., the receiver portion of the transceiver is always active; thus, the message being transmitted is coupled back on the transceiver cable),
  • Provides self-test of the collision detection circuitry at the end of each transmission,
  • Contains protective circuitry which ensures that network integrity will be maintained in the event of a faulty transceiver, controller, or repeater.

See also

External links