Telephone networks are known as public telephone networks.
They consist of :
- Trunk exchange .
- Local exchange .
- And lines between them .
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| Simplified Trunk Cable Diagram |
1- The Trunk Networks
Lines which are used for trunk traffic only are described as trunk lines . These networks can be designed as :
- Meshed networks
- Star networks
- Or mixed networks
- Transmission medium
- Symmetric copper pair
- Coaxial copper cable
- Optical fiber
- Air (radio )
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| Trunk /network Configuration |
