06-03-2013, 04:11 PM
Cabling and Connectors
Cabling and Connectors.pdf (Size: 182.67 KB / Downloads: 266)
• General media considerations
– Broadband versus baseband
• Baseband transmissions use digital signaling and Time
Division Multiplexing (TDM)
• Broadband transmissions use analog and Frequency Division
Multiplexing(FDM)
– Dialog modes: Simplex, half duplex and full duplex
– Media interference
• Electromagnetic interference (EMI) and cross talk
• Network media vary in their resistance to the effect of EMC.
– UTP is susceptible and fiber is resistant
Network Media
• Carry signals between computers: Cable-based media and
wireless networking.
• Cable-based media
– Coaxial
• Copper wire to conduct the signals electronically
• Was the choice for LAN for many years.
• Retiring
– Twisted pair
• Copper wire to conduct too
• More popular than coaxial
– Fiber-optic
• Uses glass or plastic conductor and transmits the signals as light
• High Cost. Restricted to where segment length and higher
speeds are needed.
– Server room, backbone
Thick coax
• The chance you will encounter a network using
thick coaxial cable is slim
• Thick coax, RG-8 is more robust and harder to
damage
• More resistant to attenuation, crosstalk and EMI,
found popularity to as a network backbone. Faster
fiber-optic media has all and taken over in this
role.
• Need vampire tap, a special connector that pierces
the thick cable to copper core, and a drop cable to
connect a LAN device.
Fiber-optic cable
• Use light transmissions
• EMI, crosstalk and attenuation become no issue.
• Well suited for data, video and voice
transmissions
• Most secure of all cable media
• Installation and maintenance procedures require
skills
• Cost of cable
• Cost of retrofitting of existing network equipment
because incompatible with most electronic
network equipment
Wireless media
• Three types:
– Radio wave
– Infrared
– Microwave
• Speeds of wireless solutions don’t keep pace with
cable solutions
• Installation and maintenance are far more
complicated and costly.
• Some solutions require line-of-sight, such as
infrared and microwave.