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Simulate DSLAM with Switch/Ethernet trasceiver Edit

DSLAM functionality can be simulated by connecting an Ethernet extender from http://www.versatek.com/products/ethernet_extender.htm to a layer-2 or 3 switch.

Connect a layer-2 switch to a Lxt971Aphy transceiver which converts the three volt levels of the Ethernet physical layer to binary two as explained at FreeSpaceOptics. The two voltage levels is pulsed down a two wire system using OFDM modulation at -48 volts for an Ethernet over copper solution to a distance of 4km or 600m at increased bandwidth(100Meg) using DSP or FpGa. VDSL physical layer protocol will be used.

Due to the internal resistance of copper wire the signal will be attentuated at 600m. Physically on a scope the square voltage pulsed becomes rounded. A buffer/http://en.wikipedia.org/wiki/Schmidt_trigger spaced every 600m repeats the -48volts , forming any number of hops like a fiber switch. Fiber only allows on/off light pulses, by using OFDM DSP based modulation on copperm, fiber like on/off functionality is emulated, achieving the same type of unlimited repeater nodes.

Thus a 100Meg Ethernet signal can be extended for over 10km-100km over a single twisted pair copper using repeaters every 600meters. The eight wires used in Ethernet is according to the PHY layer specification , intended for use over short distances creating three voltage levels. But computers work on 0/1 or 0/5volt binary logic only.

Normal 100Meg copper based switches allows only four daisy chained connections because each switch has to convert from three level voltage at PHY layer to MAC and data layer which takes time measured as latency.

Lay cabling on the residential walls forming a mini-WAN between all the houses in a block. Split the cabling at multiple intervals so that only a section could be stolen and not the entire cable on a residential walls linked removed.

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