Cabling pinouts
Turn the RJ-45 Connector over so that the spring clip is facing towards the ground. Pin1 is the first conductor on the left.
Wiring is typically 22 or 24AWG. When crimping there should not be more than 0.5in of untwisted cable.  Patch cables should be made of stranded wire for flexibility.

Straight-Through
Wires used for data:
Only 2 pairs of the 4 are used.
Send - 1, 2
Receive - 3, 6

EIA/TIA T568A
Pin1 - Green&White
Pin2 - Green
Pin3 - Orange&White
Pin4 - Blue
Pin5 - Blue&White
Pin6 - Orange
Pin7 - Brown&White
Pin8 - Brown


EIA/TIA T568B (Accepted industry standard since 2001)
Pin1 - Orange&White
Pin2 - Orange
Pin3 - Green&White
Pin4 - Blue
Pin5 - Blue&White
Pin6 - Green
Pin7 - Brown&White
Pin8 - Brown



Loopback Plug

Crossover
1 -> 3
2 -> 6
3 -> 1
6 -> 2

EIA/TIA T568A
EndA
Pin1 - Green&White
Pin2 - Green
Pin3 - Orange&White
Pin4 - Blue
Pin5 - Blue&White
Pin6 - Orange
Pin7 - Brown&White
Pin8 - Brown

EndB
Pin1 - Orange&White
Pin2 - Orange
Pin3 - Green &White
Pin4 - Blue
Pin5 - Blue&White
Pin6 - Green
Pin7 - Brown&White
Pin8 - Brown

EIA/TIA T568B
EndA
Pin1 - Orange&White
Pin2 - Orange
Pin3 - Green&White
Pin4 - Blue
Pin5 - Blue&White
Pin6 - Green
Pin7 - Brown&White
Pin8 - Brown

EndB
Pin1 - Green&White
Pin2 - Green
Pin3 - Orange&White
Pin4 - Blue
Pin5 - Blue&White
Pin6 - Orange
Pin7 - Brown&White
Pin8 - Brown



Max distance per segment
802.11b (Wireless LAN)                                         100m
802.15.1 (Bluetooth)                                                10m (approx?)
10Base2 (Thinnet)  HalfDuplex                             185m
10Base5 (Thicknet) HalfDuplex                            500m
10BaseFL (Fiber)                                                     2000m (multimode) 5000m (singlemode)
10BaseT/100BaseT (UTP, STP)                           100m
100BaseFX (Fiber)                                                   412m (half-duplex MM) 2000m (full-duplex MM) 15000m (SM)
1000BaseT                                                                100m
1000BaseZX (SM Fiber)                                         100km
1000BaseLX (Fiber)
10GBaseLR (Fiber)

Minimum distance between nodes
10Base2 (Thinnet)                                                   0.5m
10Base5 (Thicknet)                                                 2.5m

1 meter = 3 feet

Types of cabling
Coax:
RG-8 (50 Ohms): Thick Ethernet
RG-58 (50 Ohms): Thin Ethernet
RG-59/RG-6 (75 Ohms): CATV, Broadband
RG-62 (93 Ohms): ARCNET

Twisted-Pair:
Cat1 = Regular analog phone line
Cat2 = 4Mbps
Cat3 = 10Mbps
Cat4 = 20Mbps
Cat5 = 100Mbps

100BaseTX requires Cat5 (uses 2 pairs)
100BaseT4 requires Cat3 (uses all 4 pairs)

Fiber:
Mulitimode - LED
Singlemode - Laser
Connectors - SC, ST, MT-RJ, LC

Racks
1(R)U = 1.75 inches
Typical rack is about 42U
Racks must be stacked with the heaviest items at the bottom to the lightest near the top.