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wilsonchtam

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Is the signal within a LAN all digital

I have a discucssion with my friend about digital or analog signal. I know that from a modem will translate (or modulate)  the digital signal from the computer or router to an analog signal and send to the network. Does it means that all the signal within a simple home LAN is digital ? I can transfer almost 0.5 GBit/s with my LANs. What is the signal format in that cat6 cable. Is it really digital ? Or the digital signal is actually embedded inside some analog signal ?
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eeRoot

Yes, it is a digital signal.  The spec is defined under IEEE 802.3
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Hi eeRoot,
Thanks for your quick respond. Does 802.3 specify the physical layer needs to be a square wave with 1 or 0 ?
My next question is 'What is the frequency in the cat6 cable' ? Can the frequency transfer 1Gbit/s without any modulation or multiplexing ?

Thanks
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Patmac951
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Yes, 802.3 defines the signal as a square wave, with different specs for the different types of cabling and transmission speeds.

The spec for Cat6 calls for 200 - 250 MHz.  And a 1 Gbps connection does require modulation.

I don't *think* there is any multiplexing in a standard 1 Gbps Cat6 connection, although there may be some proprietary/unique setups that do.
Thanks eeRoot.
I just checked the link your provided. 1000BASE/T (Gig E) uses all four pairs. Each pair sends data bi-directionally. Signals are variations of sine waves; the peak voltage of each "wave" is 5 levels.
That's why it can provide the 1Gbps with a 200Mhz.
The next question make the answer complete