Node-to-node data transfer

In <a href="/facts/Telecommunications/vxoj1cxR">telecommunications</a>, node-to-node data transfer is the movement of data from one <a href="/facts/Node_(networking)/LBp2vNcJ">node</a> of a <a href="/facts/Telecommunications_network/NFCX0STS">network</a> to the next. In the <a href="/facts/OSI_model/oxN9Xhjz">OSI model</a> it is handled by the lowest two layers, the <a href="/facts/Data_link_layer/K9yPufbt">data link layer</a> and the <a href="/facts/Physical_layer/WuATCrVw">physical layer</a>.
In most communication systems, the transmitting point applies <a href="/facts/Source_coding/gMFuY4FT">source coding</a>, followed by <a href="/facts/Channel_coding/cLUTUJrA">channel coding</a>, and lastly, <a href="/facts/Line_coding/x9IuaYNL">line coding</a>. This produces the <a href="/facts/Baseband/yC0jJwbL">baseband</a> signal. The presence of filters may perform <a href="/facts/Pulse_shaping/GrhYVMUJ">pulse shaping</a>. Some systems then use <a href="/facts/Modulation/aAXPjINv">modulation</a> to multiplex many baseband signals into a <a href="/facts/Broadband/nEn3A95N">broadband</a> signal. The receiver un-does these transformations in reverse order: demodulation, trellis decoding, error detection and correction, decompression.
Some communication systems omit one or more of these steps, or use techniques that combine several of these steps together. For example, a <a href="/facts/Morse_code/GXwCl1HV">Morse code</a> transmitter combines source coding, channel coding, and line coding into one step, typically followed by an <a href="/facts/Amplitude_modulation/3sTxsXk6">amplitude modulation</a> step. <a href="/facts/Barcode/Mkh4cCTp">Barcodes</a>, on the other hand, add a checksum digit during channel coding, then translate each digit into a barcode symbol during line coding, omitting modulation.

Node-to-node data transfer open-in-new

Node-to-node data transfer