I- Public Switched Telephone Network (PSTN) yiqoqo lomhlaba wonke lezinxushunxuswe eziklanyelwe ukusekela ukuxhumana kwezwi okuguquguqukayo. I-PSTN inikeza insizakalo yendabuko ye-Plain Old Telephone (POTS) - eyaziwa nangokuthi isevisi yocingo yomhlaba - ezindaweni zokuhlala nezinye izikhungo eziningi. Izingxenye ze-PSTN nazo zisetshenziselwa izinsizakalo zokuxhuma kwi-inthanethi kubandakanya i- Digital Subscriber Line (DSL) ne- Voice Over Internet Protocol (VoIP) .
I-PSTN ingenye yezobuchwepheshe bokusekelwa kocingo lwezokuxhumana nge- telephony . Yize izinhlobo zokuqala ze-telephony ezifaka i-PSTN konke zixhomeke ekubonisweni kwe-analog, ubuchwepheshe be-telephony bwanamuhla busebenzisa ukusayinwa kwe-digital, ukusebenza nedatha yedijithali, futhi kusekela uxhumano lwe-Intanethi. Ukukhishwa kwe-telephony ye-inthanethi kuvumela kokubili izwi kanye nedatha ukuba babelane ngamanethiwekhi afanayo, ukuguqulwa ukuthi imboni yezokuxhumana emhlabeni wonke isondela (ikakhulukazi ngezizathu zezezimali). Inselelo enkulu efonini ye-inthanethi ukufezekisa izinga eliphakeme kakhulu lokuthembeka kanye nezinga eliphezulu ukuthi izinhlelo zocingo zendabuko zitholakale.
Umlando we-PSTN Technology
Amanethiwekhi wocingo akhuliswa emhlabeni wonke phakathi neminyaka ye-1900 njengoba amakholi aqala ukujwayela emakhaya. Amanethiwekhi omakhalekhukhwini asebekhulile asetshenziselwa ukusayina kwe-analog kodwa kancane kancane athuthukiswa ukusebenzisa ingqalasizinda ye-digital. Iningi labantu lihlobanisa i-PSTN ne-wiring yethusi etholakala emakhaya amaningi nakuba ingqalasizinda ye-PSTN yanamuhla isebenzisa izintambo ze-fiber optic futhi ishiya ithusi kuphela okuthiwa "i-mile yokugcina" yocingo phakathi kwekhaya nomhlinzeki wezingcingo zokuxhumana.I-PSTN isebenzisa i- SS7 ukusayina protocol.
Amakholi asekhaya we-PSTN axhunyiwe emadalazini odonga afakwe emakhaya asebenzisa izintambo zocingo nama connectors e-RJ11. Izindawo zokuhlala azihlali zihlala kuzo zonke izindawo ezifanele, kodwa abaninikhaya bangakwazi ukufaka ama-jacks abo ocingweni ngolunye ulwazi oluyisisekelo lwe-wiring kagesi.
Isixhumanisi esisodwa se-PSTN sisekela ama- kilobits angu 64 ngamaminithi (Kbps) we-bandwidth yedatha. Umzila wefoni we-PSTN ungasetshenziswa namamodeli wenethiwekhi yendabuko yokudida-up yokuxhuma ikhompyutha ku-intanethi. Ezinsukwini zakuqala zeWorld Wide Web (WWW) , lokhu kwakuyiyona ndlela eyinhloko yokufinyeleleka kwe-intanethi ekhaya kodwa yenziwe ingasebenzi ngamasevisi e-intanethi e- broadband . Ukuxhumeka kwe-inthanethi ye-Dial-up kusekelwe ku-56 Kbps.
I-PSTN vs. ISDN
I-Network Integrated Services Network (ISDN) yasungulwa njengenye indlela eya ku-PSTN enikezela kokubili isevisi yocingo kanye nokwesekwa kwedatha yedijithali. I-ISDN yathola ukuthandwa kwamabhizinisi amakhulu ngoba ikhono layo lokusekela izinombolo ezinkulu zamafoni ngezindleko zokufaka phansi. Yanikezwa nabathengi njengendlela ehlukile yokufinyelela kwe-Inthanethi esekela i-128 Kbps.
I-PSTN vs. VoIP
I-Voice Over Protocol Protocol (VoIP) , ngezinye izikhathi futhi ebizwa ngokuthi i- IP telephony , yenzelwe ukufaka insizakalo yocingo yokushintshanisa isifundazwe kokubili i-PSTN ne-ISDN ngepakethe ishintshi uhlelo olusekelwe ku- Inthanethi Protocol (IP) . Izizukulwane zokuqala zezinsizakalo zeVoIP zibhekene nokuthembeka nezinkinga zekhwalithi ezizwakalayo kodwa kancane kancane zithuthukisiwe ngokuhamba kwesikhathi.