Local loop

<h2 id="infrastructure">Infrastructure</h2>
<p>Traditionally, the local loop was an <a href="/facts/Electrical_circuit/zt94kTW0">electrical circuit</a> in the form of a single pair of conductors from the telephone on the customer's premises to the local <a href="/facts/Telephone_exchange/PaRpGm8I">telephone exchange</a>. <a href="/facts/Single-wire_earth_return/5j61avwv">Single-wire earth return</a> lines had been used in some countries until the introduction of electric tramways from the 1900s made them unusable.
</p><p>Historically the first section was often an aerial open-wire line, with several conductors attached to porcelain insulators on cross-arms on "telegraph" poles. Hence <a href="/facts/Party_line_(telephony)/CsRE9v6g">party line</a> service was often given to residential customers to minimise the number of local loops required. Usually all these circuits went into aerial or buried cables with a <a href="/facts/Twisted_pair/L426Jk2C">twisted pair</a> for each local loop nearer the exchange, see <a href="/facts/Outside_plant/p3Y70bUe">outside plant</a>.
</p><p>Modern implementations may include a <a href="/facts/Digital_loop_carrier/RMt3Uzc3">digital loop carrier</a> system segment or <a href="/facts/Fiber_optic/5ruuIFbj">fiber optic</a> transmission system. The local loop may terminate at a circuit switch owned by a <a href="/facts/Competitive_local_exchange_carrier/tzF93Bcj">competitive local exchange carrier</a> and housed in a <a href="/facts/Point_of_presence/GIvoTNvx">point of presence</a> (POP), which typically is an incumbent local exchange carrier telephone exchange. A local loop supports voice and/or data communications applications in the following ways:
</p>
<ul><li>analog voice and signaling used in traditional <a href="/facts/Plain_old_telephone_service/7uEc2wFY">POTS</a></li>
<li><a href="/facts/Integrated_Services_Digital_Network/zcV99rUb">Integrated Services Digital Network</a> (ISDN)</li>
<li>variants of <a href="/facts/Digital_subscriber_line/3pY5osov">digital subscriber line</a> (DSL).</li></ul>
<p>The term "local loop" is sometimes used for any "<a href="/facts/Last_mile_(telecommunications)/8TkkKm8e">last mile</a>" connection to the customer, regardless of technology or intended purpose. Local loop interrelations in this sense include:
</p>
<ul><li>Electric power lines.</li>
<li>Cable connections used with television, internet and telephone.</li>
<li>Wireless signals or local loop (WLL): <a href="/facts/Local_multipoint_distribution_service/FAlYC3Qp">LMDS</a>, <a href="/facts/WiMAX/tz9zpKHU">WiMAX</a>, <a href="/facts/GPRS/c4SJD7ov">GPRS</a>, <a href="/facts/HSDPA/4S6Mz83J">HSDPA</a>, <a href="/facts/DECT/CpPhUAWt">DECT</a></li>
<li>Satellite connections for beamed signal.</li>
<li>Optical or fiber optics services.</li></ul>
<h2 id="see-also">See also</h2>
<ul><li><a href="/facts/Access_network/ybK0Nf5f">Access network</a></li>
<li><a href="/facts/ISDN/zcV99rUb">ISDN</a> (Integrated Services Digital Network)</li>
<li><a href="/facts/Local-loop_unbundling/qwgR077P">Local-loop unbundling</a></li>
<li><a href="/facts/Metallic_path_facilities/QxRaWlfI">Metallic path facilities</a></li>
<li><a href="/facts/Outside_plant/p3Y70bUe">Outside plant</a> (as an instance of a local loop)</li>
<li><a href="/facts/Serving_area_interface/MNm1dDIw">Serving area interface</a></li>
<li><a href="/facts/Telephone_line/YdKUAka9">Telephone line</a></li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>"What is a local loop?". Superior Essex Communications. Retrieved 2022-08-12. <a href="https://superioressexcommunications.com/faqs/what-is-a-local-loop/" target="_blank">https://superioressexcommunications.com/faqs/what-is-a-local-loop/</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>"The corDECT Wireless Local Loop: Capacity Predictions". <a href="https://www.researchgate.net/publication/2888455_The_corDECT_Wireless_Local_Loop_Capacity_Predictions" target="_blank">https://www.researchgate.net/publication/2888455_The_corDECT_Wireless_Local_Loop_Capacity_Predictions</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
</ol>

Local loop open-in-new

Local loop