mirror of https://github.com/tLDP/LDP
parent
8f039ee479
commit
6f3fbbb559
|
@ -2,8 +2,6 @@
|
||||||
|
|
||||||
<title>Media-Types</title>
|
<title>Media-Types</title>
|
||||||
|
|
||||||
Media Types
|
|
||||||
|
|
||||||
<para>
|
<para>
|
||||||
Common network media include twisted pair (UTP and STP), coaxial cable,
|
Common network media include twisted pair (UTP and STP), coaxial cable,
|
||||||
fiber-optic cable, and wireless transmissions via infrared and radio waves.
|
fiber-optic cable, and wireless transmissions via infrared and radio waves.
|
||||||
|
@ -12,10 +10,12 @@ their vulnerability to EMI and eavesdropping, their bandwidth, and the
|
||||||
maximum distance at which they can be used.
|
maximum distance at which they can be used.
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
Twisted Pair Ethernet Cable
|
<para><variablelist>
|
||||||
|
|
||||||
Unshielded Twisted Pair (UTP)
|
<varlistentry><term>Twisted Pair Ethernet Cable</term>
|
||||||
|
|
||||||
|
<varlistentry><term>Unshielded Twisted Pair (UTP)</term>
|
||||||
|
<listitem><para>
|
||||||
<para>
|
<para>
|
||||||
UTP is the most common type of network cable in use today. UTP consits of
|
UTP is the most common type of network cable in use today. UTP consits of
|
||||||
one or more pairs of insulated copper wires. The wires are twisted together
|
one or more pairs of insulated copper wires. The wires are twisted together
|
||||||
|
@ -44,6 +44,8 @@ and Category 5 is the highest-quality network cable. The UTP categories and
|
||||||
the bandwidth they support are summarized below.
|
the bandwidth they support are summarized below.
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
|
<para>
|
||||||
|
<screen>
|
||||||
Category Maximum Data and Transfer Rate Description
|
Category Maximum Data and Transfer Rate Description
|
||||||
3 10 Mbps Least expensive network cable, commonly used
|
3 10 Mbps Least expensive network cable, commonly used
|
||||||
4 16 Mbps Medium quality; rarely used
|
4 16 Mbps Medium quality; rarely used
|
||||||
|
@ -52,9 +54,11 @@ Category Maximum Data and Transfer Rate Description
|
||||||
> Start Binh
|
> Start Binh
|
||||||
5 1000Mbps Highest Quality
|
5 1000Mbps Highest Quality
|
||||||
> End Binh
|
> End Binh
|
||||||
|
</screen>
|
||||||
|
</para>
|
||||||
|
|
||||||
Shielded Twisted Pair (STP)
|
<varlistentry><term>Shielded Twisted Pair (STP)</term>
|
||||||
|
<listitem><para>
|
||||||
<para>
|
<para>
|
||||||
STP cable is similar to UTP, but inclues a foil or wire mesh shield
|
STP cable is similar to UTP, but inclues a foil or wire mesh shield
|
||||||
between the wire pairs and the outer insulation. The shield is electrically
|
between the wire pairs and the outer insulation. The shield is electrically
|
||||||
|
@ -68,8 +72,11 @@ susceptible to EMI and eavesdropping. The reduced inteference allows for higher
|
||||||
bandwidth, potentially as high as 500 Mbps.
|
bandwidth, potentially as high as 500 Mbps.
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
Coaxial
|
</para></listitem></varlistentry>
|
||||||
|
|
||||||
|
<varlistentry><term>Coaxial</term>
|
||||||
|
<listitem><para>
|
||||||
|
|
||||||
<para>
|
<para>
|
||||||
Coaxial Cable consists of a single thick copper wire surrounded by an
|
Coaxial Cable consists of a single thick copper wire surrounded by an
|
||||||
insulator. A shield surrounding the insulator is used as the second conductor,
|
insulator. A shield surrounding the insulator is used as the second conductor,
|
||||||
|
@ -104,8 +111,8 @@ RG-62 93 ohms ARCnet
|
||||||
</screen>
|
</screen>
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
Fiber Optic
|
Fiber Optic</term>
|
||||||
|
<listitem><para>
|
||||||
<para>
|
<para>
|
||||||
A fiber optic cable consists of a thin glass or clear plastic fiber encased
|
A fiber optic cable consists of a thin glass or clear plastic fiber encased
|
||||||
in a protective jacket. Signals are sent through the cable in form of light.
|
in a protective jacket. Signals are sent through the cable in form of light.
|
||||||
|
@ -119,7 +126,7 @@ high bandwidth (up to 2 Gbps (gigabits per second) and extremely low attenuation
|
||||||
Fiber cable can reach distances ranging from severak miles for multimode cable
|
Fiber cable can reach distances ranging from severak miles for multimode cable
|
||||||
to hundreds of miles for single-mode cable.
|
to hundreds of miles for single-mode cable.
|
||||||
|
|
||||||
Infrared
|
Infrared</term>
|
||||||
|
|
||||||
<para>
|
<para>
|
||||||
Wireless infrared networking systems are modulated beams of infrared light to
|
Wireless infrared networking systems are modulated beams of infrared light to
|
||||||
|
@ -196,7 +203,6 @@ nearly global range. The bandwidth can be as high as 10 Mbps, but the satellite
|
||||||
relays cause delays that may impair real-time communication. These systems are
|
relays cause delays that may impair real-time communication. These systems are
|
||||||
more expensive than wireless communication.
|
more expensive than wireless communication.
|
||||||
|
|
||||||
|
|
||||||
<para>
|
<para>
|
||||||
Please note that any information after this point in this section is largely
|
Please note that any information after this point in this section is largely
|
||||||
redundant as these technologies have been superceded (from the perspective of
|
redundant as these technologies have been superceded (from the perspective of
|
||||||
|
@ -204,86 +210,7 @@ being economically more viable and also technologically superior) by
|
||||||
those that have been outlined above.
|
those that have been outlined above.
|
||||||
</para>
|
</para>
|
||||||
|
|
||||||
Serial NULL Modem cable
|
- Serial NULL Modem cable
|
||||||
|
- Parallel port cable (PLIP cable)
|
||||||
<para>
|
|
||||||
Not all NULL modem cables are alike. Many null modem cables do little more
|
|
||||||
than trick your computer into thinking all the appropriate signals are present
|
|
||||||
and swap transmit and receive data. This is ok but means that you must use
|
|
||||||
software flow control (XON/XOFF) which is less efficient than hardware flow
|
|
||||||
control. The following cable provides the best possible signalling between
|
|
||||||
machines and allows you to use hardware (RTS/CTS) flow control.
|
|
||||||
</para>
|
|
||||||
|
|
||||||
<para>
|
|
||||||
<screen>
|
|
||||||
Pin Name Pin Pin
|
|
||||||
Tx Data 2 ----------------------------- 3
|
|
||||||
Rx Data 3 ----------------------------- 2
|
|
||||||
RTS 4 ----------------------------- 5
|
|
||||||
CTS 5 ----------------------------- 4
|
|
||||||
Ground 7 ----------------------------- 7
|
|
||||||
DTR 20 -\--------------------------- 8
|
|
||||||
DSR 6 -/
|
|
||||||
RLSD/DCD 8 ---------------------------/- 20
|
|
||||||
\- 6
|
|
||||||
</screen>
|
|
||||||
</para>
|
|
||||||
|
|
||||||
Parallel port cable (PLIP cable)
|
|
||||||
|
|
||||||
<para>
|
|
||||||
If you intend to use the PLIP protocol between two machines then this
|
|
||||||
cable will work for you irrespective of what sort of parallel ports you
|
|
||||||
have installed.
|
|
||||||
</para>
|
|
||||||
|
|
||||||
<para>
|
|
||||||
<screen>
|
|
||||||
Pin Name pin pin
|
|
||||||
STROBE 1*
|
|
||||||
D0->ERROR 2 ----------- 15
|
|
||||||
D1->SLCT 3 ----------- 13
|
|
||||||
D2->PAPOUT 4 ----------- 12
|
|
||||||
D3->ACK 5 ----------- 10
|
|
||||||
D4->BUSY 6 ----------- 11
|
|
||||||
D5 7*
|
|
||||||
D6 8*
|
|
||||||
D7 9*
|
|
||||||
ACK->D3 10 ----------- 5
|
|
||||||
BUSY->D4 11 ----------- 6
|
|
||||||
PAPOUT->D2 12 ----------- 4
|
|
||||||
SLCT->D1 13 ----------- 3
|
|
||||||
FEED 14*
|
|
||||||
ERROR->D0 15 ----------- 2
|
|
||||||
INIT 16*
|
|
||||||
SLCTIN 17*
|
|
||||||
GROUND 25 ----------- 25
|
|
||||||
</screen>
|
|
||||||
</para>
|
|
||||||
|
|
||||||
Notes:
|
|
||||||
|
|
||||||
· Do not connect the pins marked with an asterisk `*'.
|
|
||||||
· Extra grounds are 18,19,20,21,22,23 and 24.
|
|
||||||
· If the cable you are using has a metallic shield, it should be
|
|
||||||
connected to the metallic DB-25 shell at one end only.
|
|
||||||
|
|
||||||
<para>
|
|
||||||
Warning: A miswired PLIP cable can destroy your controller card. Be very
|
|
||||||
careful and double check every connection to ensure you don't cause yourself
|
|
||||||
any unnecessary work or heartache.
|
|
||||||
</para>
|
|
||||||
|
|
||||||
<para>
|
|
||||||
While you may be able to run PLIP cables for long distances, you should avoid
|
|
||||||
it if you can. The specifications for the cable allow for a cable length of
|
|
||||||
about 1 metre or so. Please be very careful when running long plip cables as
|
|
||||||
sources of strong electromagnetic fields such as lightning, power lines and
|
|
||||||
radio transmitters can interfere with and sometimes even damage your controller.
|
|
||||||
If you really want to connect two of your computers over a large distance you
|
|
||||||
really should be looking at alternatives such as obtaining a pair of thin-net
|
|
||||||
ethernet cards and running some coaxial cable.
|
|
||||||
</para>
|
|
||||||
|
|
||||||
</sect1>
|
</sect1>
|
||||||
|
|
Loading…
Reference in New Issue