{"id":586,"date":"2010-03-05T17:35:30","date_gmt":"2010-03-05T16:35:30","guid":{"rendered":"http:\/\/ccievoice.ksiazek.be\/?p=586"},"modified":"2025-01-11T18:28:04","modified_gmt":"2025-01-11T17:28:04","slug":"isdn-bripri","status":"publish","type":"post","link":"https:\/\/collaboration.ksiazek.be\/?p=586","title":{"rendered":"ISDN (BRI\/PRI)"},"content":{"rendered":"<p>ISDN is a digital transport service that can support both Data and Voice over existing telephone wires. There are 2 types of ISDN:<\/p>\n<blockquote>\n<ul>\n<li>Basic Rate ISDN &#8211; BRI : This provides 2 x 64 Kbps bearer channels and a 16 Kbps signaling channel. It represents then (2B+1D) channels , so 144Kbps<\/li>\n<li>Primary Rate ISDN &#8211; PRI : this provides 23 or 30 x 64 Kbps beare channels depending on whether it is delivered as a T1 or an E1. It represents then (23B+1D) channels for a T1 and (30B+1D) for an E1<\/li>\n<\/ul>\n<\/blockquote>\n<p>At Layer2, ISDN signaling is provided by the Link Access Procedure on the D channel (LAPD) which is relying on Q920\/921 messages.<\/p>\n<p>At Layer3, ISDN call control signaling and access to service are specified by the Q931\/932 messages suchg as Setup, Alerting, Connect ,&#8230;<\/p>\n<p>Now as the network is not end-to-end all the time, you can encounter that you don&#8217;t receive anymore busy tone after the destination is busy. It is normal as once the ISDN network has sent the busy tone to the IP Phone, it iniatiates a normal call clearing so a disconnect, then you can fix this on the your side by setting the following command <span style=\"color: #ff0000;\"><strong><em>voice call convert-discpi-to-prog<\/em><\/strong><\/span> to force the gateway to send the busy tone on the IP end even if the ISDN side is torn down<\/p>\n","protected":false},"excerpt":{"rendered":"<p>ISDN is a digital transport service that can support both Data and Voice over existing telephone wires. There are 2 types of ISDN: Basic Rate ISDN &#8211; BRI : This provides 2 x 64 Kbps bearer channels and a 16 Kbps signaling channel. It represents then (2B+1D) channels , so 144Kbps Primary Rate ISDN &#8211; [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[1,24,33],"tags":[53,59,196,54,197,198],"class_list":["post-586","post","type-post","status-publish","format-standard","hentry","category-non-classe","category-uncategorized","category-written-theory","tag-bri","tag-ccie-voice-written","tag-isdn","tag-pri","tag-q921","tag-q931"],"_links":{"self":[{"href":"https:\/\/collaboration.ksiazek.be\/index.php?rest_route=\/wp\/v2\/posts\/586","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/collaboration.ksiazek.be\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/collaboration.ksiazek.be\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/collaboration.ksiazek.be\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/collaboration.ksiazek.be\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=586"}],"version-history":[{"count":1,"href":"https:\/\/collaboration.ksiazek.be\/index.php?rest_route=\/wp\/v2\/posts\/586\/revisions"}],"predecessor-version":[{"id":4416,"href":"https:\/\/collaboration.ksiazek.be\/index.php?rest_route=\/wp\/v2\/posts\/586\/revisions\/4416"}],"wp:attachment":[{"href":"https:\/\/collaboration.ksiazek.be\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=586"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/collaboration.ksiazek.be\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=586"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/collaboration.ksiazek.be\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=586"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}