manly girl
Member
- Joined
- Aug 9, 2002
- Messages
- 48
My Notes: Transmission Media
This is from my IT background, but I found it very usefull in telecommunications. If you want me to expand on any dot point, just ask.
:: PHYSICAL CONNECTIONS
Called Transmission Media
Used to Join the components of a LAN.
Can be cable or wireless.
:: TWISTED PAIR CABLE
(TP) consists of two copper insulated wires entwined around each other.
Can be UTP or STP (see below)
Known as signal and return paths.
Analog or digital
Twsiting the cables reduces crosstalk (Electromagnetic interference between the two)
Range is limited to 100's of metres.
UNSHIELDED TWISTED PAIR CABLE (UTP)
Consists of a pair of twisted wires with a simple plastic encasement.
Widely used in telephone systems.
Inexpensive and widely avaliable.
Easy to install.
Can support data rates of up to 100Mbps @ 100m, however most common rate is 10Mbps.
High attenuation rate
Very susceptable to EMI (Electromagnetic Interference)
Not very secure
SHIELDED TWISTED PAIR CABLE (STP)
Metal foil insulator wrapped around twisted cables.
More expensive than UTP.
Easy to install with preconfigured cables
Supports up to 155Mbps, but most common is 16Mbps. (Speeds up to 500Mbps @ 100m)
High attenuation rate.
Some EMI
Not very secure.
:: COAXIAL CABLE
A hollow outer shielding that surrounds a single inner wire core.
Core carries signal, shielding acts as the return path
Low speed digital uses 50ohm cable
High speed digital/analog uses 75ohm cable
Thin cable costs less than STP
Thick cable costs more than STP
Both cost more than UTP
Simple Installation
Transmit 10Mbps (digital) and 400Mhz (analog)
High attenuation rate.
Effective range 2km.
Quite secure.
:: FIBRE OPTIC CABLE
Signals are converted into light and sent.
Fibre Optic consists of core (carries light), cladding (surrounds core) and coating (protects cladding).
Core and claddign are both glass.
Expensive
Difficult to install
Up to 2Gbps up to 25km.
Low attenuation.
Immune to EMI
Very secure
Digital and analog.
:: WIRELESS LAN
Low installation costs, even though equipment is still expensive
Easy to install
Portable
A wirless connection can be made to an existing LAN.
Uses transcievers (transmitter / reciever)
This is from my IT background, but I found it very usefull in telecommunications. If you want me to expand on any dot point, just ask.
:: PHYSICAL CONNECTIONS
Called Transmission Media
Used to Join the components of a LAN.
Can be cable or wireless.
:: TWISTED PAIR CABLE
(TP) consists of two copper insulated wires entwined around each other.
Can be UTP or STP (see below)
Known as signal and return paths.
Analog or digital
Twsiting the cables reduces crosstalk (Electromagnetic interference between the two)
Range is limited to 100's of metres.
UNSHIELDED TWISTED PAIR CABLE (UTP)
Consists of a pair of twisted wires with a simple plastic encasement.
Widely used in telephone systems.
Inexpensive and widely avaliable.
Easy to install.
Can support data rates of up to 100Mbps @ 100m, however most common rate is 10Mbps.
High attenuation rate
Very susceptable to EMI (Electromagnetic Interference)
Not very secure
SHIELDED TWISTED PAIR CABLE (STP)
Metal foil insulator wrapped around twisted cables.
More expensive than UTP.
Easy to install with preconfigured cables
Supports up to 155Mbps, but most common is 16Mbps. (Speeds up to 500Mbps @ 100m)
High attenuation rate.
Some EMI
Not very secure.
:: COAXIAL CABLE
A hollow outer shielding that surrounds a single inner wire core.
Core carries signal, shielding acts as the return path
Low speed digital uses 50ohm cable
High speed digital/analog uses 75ohm cable
Thin cable costs less than STP
Thick cable costs more than STP
Both cost more than UTP
Simple Installation
Transmit 10Mbps (digital) and 400Mhz (analog)
High attenuation rate.
Effective range 2km.
Quite secure.
:: FIBRE OPTIC CABLE
Signals are converted into light and sent.
Fibre Optic consists of core (carries light), cladding (surrounds core) and coating (protects cladding).
Core and claddign are both glass.
Expensive
Difficult to install
Up to 2Gbps up to 25km.
Low attenuation.
Immune to EMI
Very secure
Digital and analog.
:: WIRELESS LAN
Low installation costs, even though equipment is still expensive
Easy to install
Portable
A wirless connection can be made to an existing LAN.
Uses transcievers (transmitter / reciever)