{"id":823,"date":"2018-02-15T12:55:20","date_gmt":"2018-02-15T11:55:20","guid":{"rendered":"http:\/\/www.quisted.net\/?p=823"},"modified":"2018-02-15T12:55:20","modified_gmt":"2018-02-15T11:55:20","slug":"quality-of-service-qos","status":"publish","type":"post","link":"https:\/\/www.quisted.net\/index.php\/2018\/02\/15\/quality-of-service-qos\/","title":{"rendered":"Quality of Service I ( QoS, Models, Methods )"},"content":{"rendered":"<p><a href=\"http:\/\/vps.quisted.net\/wp-content\/uploads\/2018\/02\/QoS-Airtame-1.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-861\" src=\"http:\/\/vps.quisted.net\/wp-content\/uploads\/2018\/02\/QoS-Airtame-1.png\" alt=\"\" width=\"763\" height=\"180\" srcset=\"https:\/\/www.quisted.net\/wp-content\/uploads\/2018\/02\/QoS-Airtame-1.png 852w, https:\/\/www.quisted.net\/wp-content\/uploads\/2018\/02\/QoS-Airtame-1-300x71.png 300w, https:\/\/www.quisted.net\/wp-content\/uploads\/2018\/02\/QoS-Airtame-1-768x181.png 768w\" sizes=\"auto, (max-width: 763px) 100vw, 763px\" \/><\/a><\/p>\n<p><span style=\"color: #993366;\"><strong>What is QoS?<\/strong><\/span><\/p>\n<ul>\n<li><a href=\"http:\/\/docwiki.cisco.com\/wiki\/Quality_of_Service_Networking\" target=\"_blank\" rel=\"noopener\">http:\/\/docwiki.cisco.com\/wiki\/Quality_of_Service_Networking<\/a><\/li>\n<li>Quality of life insurance<\/li>\n<li><span style=\"color: #993366;\"><strong>The ability to dictate traffic treatment<br \/>\n<\/strong><\/span><\/p>\n<ul>\n<li>Prioritization.\n<ul>\n<li>Only happens with congestion.<\/li>\n<\/ul>\n<\/li>\n<li>Shaping \/ Policing.\n<ul>\n<li><em>Shaping: Mold the traffic down to a specific speed.<\/em><\/li>\n<li><em>Policing: &#8216;evil&#8217; traffic types ( p2p \/ video ).<\/em><\/li>\n<\/ul>\n<\/li>\n<li>Advanced Strategies ( <em>WRED &#8211; Weighted random early detection<\/em>)\n<ul>\n<li>Drop selective TCP streams so it won&#8217;t hit max.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<li><span style=\"color: #993366;\"><strong>Strategies to fight the enemy<\/strong><\/span>\n<ul>\n<li><em><strong>Delay<\/strong> ( how long it takes for a <span style=\"color: #3366ff;\">Packet A<\/span> to get to the other side).<br \/>\n<\/em><\/li>\n<li><em><strong>Jitter<\/strong> ( Delay variation, Times between <span style=\"color: #3366ff;\">Packets A<\/span>,<span style=\"color: #339966;\">Packet B,<\/span>and <span style=\"color: #ff0000;\">Packet C<\/span> taking to get to the other side)<br \/>\n<\/em><\/li>\n<li><em><strong>Packetloss<\/strong><br \/>\n<\/em><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n<table id=\"tablepress-10\" class=\"tablepress tablepress-id-10\">\n<thead>\n<tr class=\"row-1\">\n\t<td class=\"column-1\"><\/td><th class=\"column-2\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.quisted.net\/wp-content\/uploads\/2018\/02\/phone.png\" alt=\"\" width=\"50\" height=\"43\" class=\"alignnone size-full wp-image-866\" \/> Audio Requirements<\/th><th class=\"column-3\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.quisted.net\/wp-content\/uploads\/2018\/02\/video.png\" alt=\"\" width=\"51\" height=\"41\" class=\"alignnone size-full wp-image-865\" \/> Video Requirements<\/th>\n<\/tr>\n<\/thead>\n<tbody class=\"row-striping row-hover\">\n<tr class=\"row-2\">\n\t<td class=\"column-1\">Jitter<\/td><td class=\"column-2\">< 30ms<\/td><td class=\"column-3\">< 30ms<\/td>\n<\/tr>\n<tr class=\"row-3\">\n\t<td class=\"column-1\">Delay<\/td><td class=\"column-2\">< 150ms<\/td><td class=\"column-3\">< 150ms<\/td>\n<\/tr>\n<tr class=\"row-4\">\n\t<td class=\"column-1\">Loss <\/td><td class=\"column-2\">< 1%<\/td><td class=\"column-3\">< 1%<\/td>\n<\/tr>\n<tr class=\"row-5\">\n\t<td class=\"column-1\">QoS:<\/td><td class=\"column-2\">DSCP EF<\/td><td class=\"column-3\">DSCP AF41<\/td>\n<\/tr>\n<tr class=\"row-6\">\n\t<td class=\"column-1\">Bandwith<\/td><td class=\"column-2\">Low<\/td><td class=\"column-3\">High<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<!-- #tablepress-10 from cache -->\n<ul>\n<li><a href=\"https:\/\/www.cisco.com\/c\/en\/us\/td\/docs\/switches\/datacenter\/nexus1000\/sw\/4_0\/qos\/configuration\/guide\/nexus1000v_qos\/qos_6dscp_val.pdf\" target=\"_blank\" rel=\"noopener\">https:\/\/www.cisco.com\/c\/en\/us\/td\/docs\/switches\/datacenter\/nexus1000\/sw\/4_0\/qos\/configuration\/guide\/nexus1000v_qos\/qos_6dscp_val.pdf<\/a><\/li>\n<\/ul>\n<p><!--more--><\/p>\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_80 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.quisted.net\/index.php\/2018\/02\/15\/quality-of-service-qos\/#QoS_Models\" >QoS Models<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.quisted.net\/index.php\/2018\/02\/15\/quality-of-service-qos\/#QoS_Methods\" >QoS Methods<\/a><\/li><\/ul><\/nav><\/div>\n<h3><span class=\"ez-toc-section\" id=\"QoS_Models\"><\/span><span style=\"color: #993366;\"><strong>QoS Models<\/strong><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><strong>Best Effort<\/strong><\/p>\n<p><strong>Integrated Services<\/strong> ( <span style=\"color: #ff0000;\"><strong>IntServ<\/strong><\/span> ).<\/p>\n<ul>\n<li>A private courier for packets.<\/li>\n<li>Best with guaranteed bandwith ( VoIP | Video ).<\/li>\n<li><span class=\"_Tgc _s8w\"><span style=\"color: #339966;\">Tool of the trade<\/span>: Resource Reservation Protocol ( <strong>RSVP<\/strong> ).<\/span>\n<ul>\n<li><a href=\"https:\/\/www.cisco.com\/c\/dam\/en_us\/solutions\/industries\/docs\/gov\/SecuringQOSwp_072508.pdf\" target=\"_blank\" rel=\"noopener\">https:\/\/www.cisco.com\/c\/dam\/en_us\/solutions\/industries\/docs\/gov\/SecuringQOSwp_072508.pdf<\/a><\/li>\n<\/ul>\n<\/li>\n<li>It doesnt scale because it takes chunks from your bandwidth.<\/li>\n<\/ul>\n<p><strong>Differentiated Services<\/strong> ( <span style=\"color: #ff0000;\"><strong>DiffServ<\/strong><\/span> ).<\/p>\n<ul>\n<li>A lot more scaleable in comparison to IntServ.<\/li>\n<li>Prioritized delivery service for packets.<\/li>\n<li><span style=\"color: #339966;\">Tool of the trade<\/span>: Per Hop Behavior ( <strong>PHB<\/strong> ).\n<ul>\n<li><a href=\"https:\/\/en.wikipedia.org\/wiki\/Per-hop_behaviour\" target=\"_blank\" rel=\"noopener\">https:\/\/en.wikipedia.org\/wiki\/Per-hop_behaviour<\/a><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3><span class=\"ez-toc-section\" id=\"QoS_Methods\"><\/span><span style=\"color: #993366;\"><strong>QoS Methods<\/strong><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><strong>Classification<\/strong><\/p>\n<ul>\n<li>Can be done with access-list to capture certain traffic.<\/li>\n<li>\u00a0NBAR.\n<ul>\n<li>Deep packet inspection (If an aplication uses a well known port 80).<\/li>\n<li>Looks beyond the portnumber.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><strong>Marking<\/strong><\/p>\n<ul>\n<li>Labels the traffic<\/li>\n<li>Layer 2 : Class of Service ( <strong>CoS<\/strong> ) bits<\/li>\n<li>Later 3 : Type of Service ( <strong>ToS<\/strong> )\n<ul>\n<li><span class=\"st\"><em>differentiated services code point ( <\/em><\/span><strong>DSCP<\/strong> ) bits<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><strong>Queueing ( Congestion Management )<\/strong><\/p>\n<ul>\n<li><span style=\"color: #3366ff;\">Weighted Fair Queuing<\/span> ( <strong>WFQ<\/strong> )\n<ul>\n<li>Low traffic senders get priority over high traffic senders<\/li>\n<\/ul>\n<\/li>\n<li><span style=\"color: #3366ff;\">Class Based WFQ\u00a0<\/span>\n<ul>\n<li>Devides Bandwidth among classes that you define<\/li>\n<\/ul>\n<\/li>\n<li><span style=\"color: #3366ff;\">Low Latency Queuing<\/span> ( <strong>LLQ<\/strong> )\n<ul>\n<li>Combo of CB-WFQ, but adds a strict priority element.<\/li>\n<li>Used to be called <span style=\"color: #3366ff;\">Priority Queuing<\/span> <strong>PQ-CBWFQ<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><strong>Congestion Avoidance<\/strong><\/p>\n<ul>\n<li><a href=\"https:\/\/www.cisco.com\/c\/en\/us\/td\/docs\/ios\/12_2\/qos\/configuration\/guide\/fqos_c\/qcfconav.pdf\" target=\"_blank\" rel=\"noopener\">https:\/\/www.cisco.com\/c\/en\/us\/td\/docs\/ios\/12_2\/qos\/configuration\/guide\/fqos_c\/qcfconav.pdf<\/a><\/li>\n<li><a href=\"https:\/\/en.wikipedia.org\/wiki\/TCP_congestion_control\" target=\"_blank\" rel=\"noopener\">https:\/\/en.wikipedia.org\/wiki\/TCP_congestion_control<\/a><\/li>\n<\/ul>\n<p><strong>Link Efficiency<\/strong><\/p>\n<ul>\n<li><strong>Techniques used on low bandwidth connections<\/strong><\/li>\n<li><span style=\"color: #993366;\"><strong>Payload Compression<\/strong><\/span> ( Squishing the data ).\n<ul>\n<li>Trades CPU processing power for bandwidth.<\/li>\n<li>Your CPU compresses the data and decompresses the data on the other end.<\/li>\n<\/ul>\n<\/li>\n<li><strong><span style=\"color: #993366;\">Header Compression<\/span><\/strong> ( Squishing the header ( key for RTP ).\n<ul>\n<li>Very little data but a big header.<\/li>\n<li>When enabled on both ends it strips off the redundant header information.<\/li>\n<\/ul>\n<\/li>\n<li><strong><span style=\"color: #993366;\">Link Fragmentation and Interleaving<\/span><\/strong> &#8211; Blow up the big packets.\n<ul>\n<li>Always used on low bandwidth.<\/li>\n<li>Hardware Queue, it takes 214ms to put 1500 byte on a 56kbps line.\n<ul>\n<li>1500 byte gets fragmented into smaller packets<\/li>\n<li>Leaves openings for other packets like VoIP.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><strong>Where can you apply QoS methods?<\/strong><\/p>\n<p><a href=\"http:\/\/vps.quisted.net\/wp-content\/uploads\/2018\/02\/QoS.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-883\" src=\"http:\/\/vps.quisted.net\/wp-content\/uploads\/2018\/02\/QoS.png\" alt=\"\" width=\"358\" height=\"206\" srcset=\"https:\/\/www.quisted.net\/wp-content\/uploads\/2018\/02\/QoS.png 358w, https:\/\/www.quisted.net\/wp-content\/uploads\/2018\/02\/QoS-300x173.png 300w\" sizes=\"auto, (max-width: 358px) 100vw, 358px\" \/><\/a><\/p>\n<p><strong>MQC:<\/strong><\/p>\n<ol>\n<li>Classify (class-map)<\/li>\n<li>Policy ( policy-map)<\/li>\n<li>Apply<\/li>\n<\/ol>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>What is QoS? http:\/\/docwiki.cisco.com\/wiki\/Quality_of_Service_Networking Quality of life insurance The ability to dictate traffic treatment Prioritization. Only happens with congestion. Shaping \/ Policing. Shaping: Mold the traffic down to a specific speed. Policing: &#8216;evil&#8217; traffic types ( p2p \/ video ). Advanced Strategies ( WRED &#8211; Weighted random early detection) Drop selective TCP streams so it [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"footnotes":""},"categories":[2,7],"tags":[28,35,37,38,51,56,59,75,77,84,93,105,108],"class_list":["post-823","post","type-post","status-publish","format-standard","hentry","category-arc","category-qos","tag-cos","tag-delay","tag-diffserv","tag-dscp","tag-intserv","tag-jitter","tag-llq","tag-phb","tag-qos","tag-rsvp","tag-tos","tag-wfq","tag-wred"],"_links":{"self":[{"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/posts\/823","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/comments?post=823"}],"version-history":[{"count":0,"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/posts\/823\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/media?parent=823"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/categories?post=823"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.quisted.net\/index.php\/wp-json\/wp\/v2\/tags?post=823"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}