{"id":68622,"date":"2021-08-06T04:10:04","date_gmt":"2021-08-06T08:10:04","guid":{"rendered":"http:\/\/bangla.salearningschool.com\/recent-posts\/office-phone-systems-70\/"},"modified":"2021-08-06T04:10:04","modified_gmt":"2021-08-06T08:10:04","slug":"office-phone-systems-70","status":"publish","type":"post","link":"http:\/\/bangla.sitestree.com\/?p=68622","title":{"rendered":"Office Phone Systems #70"},"content":{"rendered":"<ul>\n<li> PSTN carries Voice<\/li>\n<li> Internet Carries Data &#8211; data network<\/li>\n<li> Recently, PSTNs are customized to carry data<\/li>\n<li> You can also carry voice over the data network like the Internet &#8211; called IP Telephony or VOIP.<\/li>\n<\/ul>\n<p><b>How to connect to the Voice Network &#8211; PSTN<\/b><br \/>Just connect to the phone line &#8211; applies to one user only<\/p>\n<p><b>How multiple users can connect to the Voice Network &#8211; PSTN<\/b><\/p>\n<ul>\n<li>Key System-Most basic multiuser support &#8211; good for very small offices<\/li>\n<li>PBX<\/li>\n<li>centrax<\/li>\n<\/ul>\n<p><b>Key System<\/b><\/p>\n<ul>\n<li> Uses a few trunk lines to connect to the LE or CO-central Office<\/li>\n<li> When users call, one of the free lines is used<\/li>\n<li> Each trunk line is associated with a number<\/li>\n<li> Incoming calls come to a central phone that  can be forwarded to others<\/li>\n<li> Individual users can also pick the phone<\/li>\n<li> Good only when &lt; 50 users are involved<\/li>\n<li> Recent Key Systems come with features like: Caller ID, Voice Mail, Conference Calls<\/li>\n<li> Not much scalable<\/li>\n<li> Push button to select a line<\/li>\n<\/ul>\n<p><b>PBX<\/b><\/p>\n<ul>\n<li> Works like a telephone exchange<\/li>\n<li> Has more outgoing trunk lines<\/li>\n<li> Users can call outside or inside independently<\/li>\n<li> Users can press 9 or a special key to make calls to outside<\/li>\n<li> Internal calls never leaves the internal network, hence, PBX provides security<\/li>\n<li> More scalable than the Keysystem<\/li>\n<li> Can associate a number with a particular phone<\/li>\n<li> Have features like analog extensions, digital extensions<\/li>\n<\/ul>\n<p><b>Centrex System<\/b><\/p>\n<ul>\n<li> Similar to the PBX but the telephone company handles the Centrex equipments<\/li>\n<li> The Centrex equipments do not have to be in the same building like PBX, hence Centrex is more popular withing big enterprises<\/li>\n<li> Less setup cost, more running cost<\/li>\n<li> Each phone set has a public phone number associated<\/li>\n<li> Scalable<\/li>\n<li> Can connect multiple sites without PSTN. Hence, providing IP telephony through Centrex system is easier and practical<\/li>\n<li> Installation cheaper<\/li>\n<\/ul>\n<ul>  <\/ul>\n<\/p>\n<p> From: http:\/\/sitestree.com\/?p=5027<br \/> Categories:70<br \/>Tags:<br \/> Post Data:2012-03-04 19:04:09<\/p>\n<p>\t\tShop Online: <a href='https:\/\/www.ShopForSoul.com\/' target='new' rel=\"noopener\">https:\/\/www.ShopForSoul.com\/<\/a><br \/>\n\t\t(Big Data, Cloud, Security, Machine Learning): Courses: <a href='http:\/\/Training.SitesTree.com' target='new' rel=\"noopener\"> http:\/\/Training.SitesTree.com<\/a><br \/>\n\t\tIn Bengali: <a href='http:\/\/Bangla.SaLearningSchool.com' target='new' rel=\"noopener\">http:\/\/Bangla.SaLearningSchool.com<\/a><br \/>\n\t\t<a href='http:\/\/SitesTree.com' target='new' rel=\"noopener\">http:\/\/SitesTree.com<\/a><br \/>\n\t\t8112223 Canada Inc.\/JustEtc: <a href='http:\/\/JustEtc.net' target='new' rel=\"noopener\">http:\/\/JustEtc.net (Software\/Web\/Mobile\/Big-Data\/Machine Learning) <\/a><br \/>\n\t\tShop Online: <a href='https:\/\/www.ShopForSoul.com'> https:\/\/www.ShopForSoul.com\/<\/a><br \/>\n\t\tMedium: <a href='https:\/\/medium.com\/@SayedAhmedCanada' target='new' rel=\"noopener\"> https:\/\/medium.com\/@SayedAhmedCanada <\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>PSTN carries Voice Internet Carries Data &#8211; data network Recently, PSTNs are customized to carry data You can also carry voice over the data network like the Internet &#8211; called IP Telephony or VOIP. How to connect to the Voice Network &#8211; PSTNJust connect to the phone line &#8211; applies to one user only How &hellip; <\/p>\n<p><a class=\"more-link btn\" href=\"http:\/\/bangla.sitestree.com\/?p=68622\">Continue reading<\/a><\/p>\n","protected":false},"author":8,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[1917],"tags":[],"class_list":["post-68622","post","type-post","status-publish","format-standard","hentry","category-fromsitestree-com","item-wrap"],"jetpack_sharing_enabled":true,"jetpack-related-posts":[{"id":78816,"url":"http:\/\/bangla.sitestree.com\/?p=78816","url_meta":{"origin":68622,"position":0},"title":"How Do Cell Phones Become Part of Computer Networks?","author":"Sayed","date":"September 9, 2026","format":false,"excerpt":"How Do Cell Phones Become Part of Computer Networks? 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