<?xml version="1.0" encoding="UTF-8"?><rss version="2.0"
	xmlns:content="http://purl.org/rss/1.0/modules/content/"
	xmlns:wfw="http://wellformedweb.org/CommentAPI/"
	xmlns:dc="http://purl.org/dc/elements/1.1/"
	xmlns:atom="http://www.w3.org/2005/Atom"
	xmlns:sy="http://purl.org/rss/1.0/modules/syndication/"
	xmlns:slash="http://purl.org/rss/1.0/modules/slash/"
	>

<channel>
	<title>路由協議 彙整 - 碼蟻創研工坊 - CODEANT STUDIOS</title>
	<atom:link href="http://codeant.cc/archives/tag/%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0/feed" rel="self" type="application/rss+xml" />
	<link>http://codeant.cc/archives/tag/路由協議</link>
	<description></description>
	<lastBuildDate>Mon, 15 Jul 2013 18:12:37 +0000</lastBuildDate>
	<language>zh-TW</language>
	<sy:updatePeriod>
	hourly	</sy:updatePeriod>
	<sy:updateFrequency>
	1	</sy:updateFrequency>
	<generator>https://wordpress.org/?v=6.7.2</generator>

<image>
	<url>http://codeant.cc/wp-content/uploads/2020/10/cropped-Code-Ant-Logo-2-32x32.png</url>
	<title>路由協議 彙整 - 碼蟻創研工坊 - CODEANT STUDIOS</title>
	<link>http://codeant.cc/archives/tag/路由協議</link>
	<width>32</width>
	<height>32</height>
</image> 
	<item>
		<title>影響網狀路由協議(Mesh Routing Protocol)效能的可能因素</title>
		<link>http://codeant.cc/archives/47</link>
		
		<dc:creator><![CDATA[codeant]]></dc:creator>
		<pubDate>Mon, 15 Jul 2013 18:12:37 +0000</pubDate>
				<category><![CDATA[Netowrk]]></category>
		<category><![CDATA[表頭耗損]]></category>
		<category><![CDATA[路徑選擇]]></category>
		<category><![CDATA[路由協議]]></category>
		<guid isPermaLink="false">http://codeant.cc/2013/07/16/mesh-routing-protocol-impact/</guid>

					<description><![CDATA[<p>網狀路由協議是一個可運行於無線隨意網路（MANETs）與無線網狀網路（WMNs）的路由協議，最主要的功能是提供 [&#8230;]</p>
<p>這篇文章 <a href="http://codeant.cc/archives/47">影響網狀路由協議(Mesh Routing Protocol)效能的可能因素</a> 最早出現於 <a href="http://codeant.cc">碼蟻創研工坊 - CODEANT STUDIOS</a>。</p>
]]></description>
										<content:encoded><![CDATA[<p style="text-align: left;"><span style="font-size: 16px; line-height: 26px;">網狀路由協議是一個可運行於無線隨意網路（MANETs）與無線網狀網路（WMNs）的路由協議，最主要的功能是提供一個資料傳遞的路徑。由於MANETs或是WMNs的網路拓撲是動態具有變化性也支援移動性，能否正確的選擇傳輸路徑與快速的反應當下的網路環境，將是一個影響系統效能表現的重要關鍵。<br /></span></p>
<p>  <span id="more-47"></span>  </p>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">但是不同的路由協議分別由不同的開發團隊實作，也有著不同的運行機制，下面是已知影響整體效能的可能因素：</span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">1. 額外作業時間</span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">2. 表頭耗損</span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">3. 路徑選擇的效能</span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">各網狀路由協議在多路徑的環境下時其路徑選擇的表現與差異是巨大的，探討路徑選擇對網狀路由協議的效能會產生多大的影響需要專業的知識與專門的測試環境與流程，分析額外作業時間與表頭耗損則是相對簡單。</span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">表頭耗損與Header的設計息息相關，盡可能降低表頭耗損而又滿足所需的功能式設計上的主要考量，也是一大挑戰。</span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">額外作業時間則與實作有關，包含Coding的方式，程式的設計邏輯，以及作業系統本身的條件，都是影響的因素之一。</span></div>
<div style="text-align: center;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">&nbsp;<img fetchpriority="high" decoding="async" class=" size-full wp-image-46" src="http://codeant.cc/wp-content/uploads/2013/07/images_phocagallery_Network_mesh-tx-flow.jpg" alt="mesh-tx-flow" width="558" height="331" srcset="http://codeant.cc/wp-content/uploads/2013/07/images_phocagallery_Network_mesh-tx-flow.jpg 558w, http://codeant.cc/wp-content/uploads/2013/07/images_phocagallery_Network_mesh-tx-flow-300x178.jpg 300w" sizes="(max-width: 558px) 100vw, 558px" /></span></div>
<div style="text-align: center;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">路徑選擇的效能從表面上來看，就是選則正確的路徑，也可說是最佳路徑，那麼，怎樣才是最佳路徑呢? 要考慮因素也不少，如跳數(Hop Count)、連線品質、訊號干擾、QoS等等，都可以列入計算，但脫離不了一個大原則，就是對當下現實環境的有效偵測與掌握，這是最難的。</span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">距離向量法的路由方式，由於並不需要掌握完整的網路拓撲，因此在資料傳遞的過程中，比起採用連結狀態法的路由方式，會有跳躍數過多的問題發生，這是距離向量路由法的一個特性。</span> </p>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">另外，若有一節點同時身為其他節點的最佳下一跳，其所處理的資料量與本身頻寬的負荷將會提高。這就是缺乏QoS或是負載平衡（Load Balancing）的機制，這樣的問題也會造成整體系統效能的影響。</span></div>
</p></div>
<p><a class="a2a_button_facebook" href="https://www.addtoany.com/add_to/facebook?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F47&amp;linkname=%E5%BD%B1%E9%9F%BF%E7%B6%B2%E7%8B%80%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%28Mesh%20Routing%20Protocol%29%E6%95%88%E8%83%BD%E7%9A%84%E5%8F%AF%E8%83%BD%E5%9B%A0%E7%B4%A0" title="Facebook" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_line" href="https://www.addtoany.com/add_to/line?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F47&amp;linkname=%E5%BD%B1%E9%9F%BF%E7%B6%B2%E7%8B%80%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%28Mesh%20Routing%20Protocol%29%E6%95%88%E8%83%BD%E7%9A%84%E5%8F%AF%E8%83%BD%E5%9B%A0%E7%B4%A0" title="Line" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_wechat" href="https://www.addtoany.com/add_to/wechat?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F47&amp;linkname=%E5%BD%B1%E9%9F%BF%E7%B6%B2%E7%8B%80%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%28Mesh%20Routing%20Protocol%29%E6%95%88%E8%83%BD%E7%9A%84%E5%8F%AF%E8%83%BD%E5%9B%A0%E7%B4%A0" title="WeChat" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_sina_weibo" href="https://www.addtoany.com/add_to/sina_weibo?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F47&amp;linkname=%E5%BD%B1%E9%9F%BF%E7%B6%B2%E7%8B%80%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%28Mesh%20Routing%20Protocol%29%E6%95%88%E8%83%BD%E7%9A%84%E5%8F%AF%E8%83%BD%E5%9B%A0%E7%B4%A0" title="Sina Weibo" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_qzone" href="https://www.addtoany.com/add_to/qzone?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F47&amp;linkname=%E5%BD%B1%E9%9F%BF%E7%B6%B2%E7%8B%80%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%28Mesh%20Routing%20Protocol%29%E6%95%88%E8%83%BD%E7%9A%84%E5%8F%AF%E8%83%BD%E5%9B%A0%E7%B4%A0" title="Qzone" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_linkedin" href="https://www.addtoany.com/add_to/linkedin?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F47&amp;linkname=%E5%BD%B1%E9%9F%BF%E7%B6%B2%E7%8B%80%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%28Mesh%20Routing%20Protocol%29%E6%95%88%E8%83%BD%E7%9A%84%E5%8F%AF%E8%83%BD%E5%9B%A0%E7%B4%A0" title="LinkedIn" rel="nofollow noopener" target="_blank"></a><a class="a2a_dd addtoany_share_save addtoany_share" href="https://www.addtoany.com/share#url=http%3A%2F%2Fcodeant.cc%2Farchives%2F47&#038;title=%E5%BD%B1%E9%9F%BF%E7%B6%B2%E7%8B%80%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%28Mesh%20Routing%20Protocol%29%E6%95%88%E8%83%BD%E7%9A%84%E5%8F%AF%E8%83%BD%E5%9B%A0%E7%B4%A0" data-a2a-url="http://codeant.cc/archives/47" data-a2a-title="影響網狀路由協議(Mesh Routing Protocol)效能的可能因素"></a></p><p>這篇文章 <a href="http://codeant.cc/archives/47">影響網狀路由協議(Mesh Routing Protocol)效能的可能因素</a> 最早出現於 <a href="http://codeant.cc">碼蟻創研工坊 - CODEANT STUDIOS</a>。</p>
]]></content:encoded>
					
		
		
			</item>
		<item>
		<title>網狀路由協議 &#8211; OLSR Routing Protocol</title>
		<link>http://codeant.cc/archives/43</link>
		
		<dc:creator><![CDATA[codeant]]></dc:creator>
		<pubDate>Sun, 14 Jul 2013 01:01:47 +0000</pubDate>
				<category><![CDATA[Netowrk]]></category>
		<category><![CDATA[Mesh]]></category>
		<category><![CDATA[OLSR]]></category>
		<category><![CDATA[路由協議]]></category>
		<guid isPermaLink="false">http://codeant.cc/2013/07/14/olsr-routing-protocol/</guid>

					<description><![CDATA[<p>OLSR是一個運行於OSI第三層的網狀路由協議，以UDP的方式進行路由訊息封包的資料交換，所使用的連線端口（P [&#8230;]</p>
<p>這篇文章 <a href="http://codeant.cc/archives/43">網狀路由協議 &#8211; OLSR Routing Protocol</a> 最早出現於 <a href="http://codeant.cc">碼蟻創研工坊 - CODEANT STUDIOS</a>。</p>
]]></description>
										<content:encoded><![CDATA[<p style="text-indent: 24pt; line-height: 150%; text-align: left;"><span style="font-size: 16px; line-height: 26px;">OLSR是一個運行於OSI第三層的網狀路由協議，以UDP的方式進行路由訊息封包的資料交換，所使用的連線端口（Port）為698；OLSR是目前使用最為廣泛的網狀路由協議，是屬於主動式的路由協議。</span></p>
<p>  <span id="more-43"></span>  </p>
<p style="text-indent: 24pt; line-height: 150%; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">該協議採用評估連結狀態（Link Status）的方式進行路由計算，因為採用連結狀態的路由方法，各節點必須取得完整的網路拓撲及每個節點間的路徑品質，為了避免因進行資料更新所造成的洪泛（flooding）現象，OLSR採用一種稱為Multi-Point Relay（MPR）的方式來降低系統負擔。</span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;">&nbsp;</p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">OLSR使用二種封包進行路由資訊的建立與交換，為Hello Message（HM）與Topology Control（TC）。HM封包的主要功能為連結狀態感測（link sensing）、鄰近節點偵測（neighbor detection）、選擇MPR節點的信令（MPR selection signaling），在OLSR路由協議中，每個節點都會週期性的廣播HM封包，而且HM封包不能進行再廣播；而TC封包用於傳送目前的網路拓撲狀況，它只由MPR節點進行發送或再廣播，所以可以降低因為過多的廣播封包而產生的洪泛現象。</span></p>
<p><a class="a2a_button_facebook" href="https://www.addtoany.com/add_to/facebook?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F43&amp;linkname=%E7%B6%B2%E7%8B%80%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%20%E2%80%93%20OLSR%20Routing%20Protocol" title="Facebook" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_line" href="https://www.addtoany.com/add_to/line?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F43&amp;linkname=%E7%B6%B2%E7%8B%80%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%20%E2%80%93%20OLSR%20Routing%20Protocol" title="Line" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_wechat" href="https://www.addtoany.com/add_to/wechat?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F43&amp;linkname=%E7%B6%B2%E7%8B%80%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%20%E2%80%93%20OLSR%20Routing%20Protocol" title="WeChat" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_sina_weibo" href="https://www.addtoany.com/add_to/sina_weibo?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F43&amp;linkname=%E7%B6%B2%E7%8B%80%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%20%E2%80%93%20OLSR%20Routing%20Protocol" title="Sina Weibo" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_qzone" href="https://www.addtoany.com/add_to/qzone?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F43&amp;linkname=%E7%B6%B2%E7%8B%80%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%20%E2%80%93%20OLSR%20Routing%20Protocol" title="Qzone" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_linkedin" href="https://www.addtoany.com/add_to/linkedin?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F43&amp;linkname=%E7%B6%B2%E7%8B%80%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%20%E2%80%93%20OLSR%20Routing%20Protocol" title="LinkedIn" rel="nofollow noopener" target="_blank"></a><a class="a2a_dd addtoany_share_save addtoany_share" href="https://www.addtoany.com/share#url=http%3A%2F%2Fcodeant.cc%2Farchives%2F43&#038;title=%E7%B6%B2%E7%8B%80%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%20%E2%80%93%20OLSR%20Routing%20Protocol" data-a2a-url="http://codeant.cc/archives/43" data-a2a-title="網狀路由協議 – OLSR Routing Protocol"></a></p><p>這篇文章 <a href="http://codeant.cc/archives/43">網狀路由協議 &#8211; OLSR Routing Protocol</a> 最早出現於 <a href="http://codeant.cc">碼蟻創研工坊 - CODEANT STUDIOS</a>。</p>
]]></content:encoded>
					
		
		
			</item>
		<item>
		<title>802.11s RMAODV 被動式路由協議(Mesh Routing Protocol)</title>
		<link>http://codeant.cc/archives/29</link>
		
		<dc:creator><![CDATA[codeant]]></dc:creator>
		<pubDate>Thu, 11 Jul 2013 01:02:52 +0000</pubDate>
				<category><![CDATA[Netowrk]]></category>
		<category><![CDATA[802.11s]]></category>
		<category><![CDATA[Mesh]]></category>
		<category><![CDATA[RMAODV]]></category>
		<category><![CDATA[路由協議]]></category>
		<guid isPermaLink="false">http://codeant.cc/2013/07/11/80211s-rmaodv-mesh-routing-protocol/</guid>

					<description><![CDATA[<p>802.11s RMAODV全名為Radio Metric Ad hoc On-Demand Distance [&#8230;]</p>
<p>這篇文章 <a href="http://codeant.cc/archives/29">802.11s RMAODV 被動式路由協議(Mesh Routing Protocol)</a> 最早出現於 <a href="http://codeant.cc">碼蟻創研工坊 - CODEANT STUDIOS</a>。</p>
]]></description>
										<content:encoded><![CDATA[<p style="text-indent: 24pt; line-height: 150%; text-align: left;"><span style="font-size: 16px; line-height: 26px;">802.11s RMAODV全名為Radio Metric Ad hoc On-Demand Distance Vector Radio，是一個運行在OSI第二層的網狀路由協議，屬於被動式的路由協議，採用距離向量的路由方法，是由目前使用率最高的被動式路由協議Ad hoc On-Demand Distance Vector（AODV）演化而來。</span></p>
<p>  <span id="more-29"></span>  </p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">不同的是在802.11s中PREQ封包有Target Only（TO）的旗標（flag）設定，所以在RMAODV協議中可以透過TO旗標設定成只有目的地可以回傳PREP，這是為了減少路由資訊封包在交換過程中所帶來的系統負擔，而AODV路由協議則是只要知道目的地的路徑的中間節點都可回傳PREP。</span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">802.11s其系統組成主要由下列三個裝置組成，其組成架構如圖:</span></p>
<p style="text-indent: 24pt; line-height: 150%; text-align: left;"><span style="font-size: 12pt; font-family: 'comic sans ms', sans-serif;">&nbsp;<img decoding="async" class=" size-full wp-image-26" src="http://codeant.cc/wp-content/uploads/2013/07/images_phocagallery_Network_80211s-network-arch.jpg" alt="80211s-network-arch" width="491" height="382" style="display: block; margin-left: auto; margin-right: auto;" srcset="http://codeant.cc/wp-content/uploads/2013/07/images_phocagallery_Network_80211s-network-arch.jpg 491w, http://codeant.cc/wp-content/uploads/2013/07/images_phocagallery_Network_80211s-network-arch-300x233.jpg 300w" sizes="(max-width: 491px) 100vw, 491px" /></span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">1.<span style="line-height: normal;">&nbsp; &nbsp; &nbsp;</span><strong>Mesh Portal Point</strong><strong>（</strong><strong>MPP</strong><strong>）</strong>：具有網路閘道（Gateway）的功能，負責與外部網路連結，如網際網路（Internet）。</span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">2.<span style="line-height: normal;">&nbsp; &nbsp;&nbsp;</span><strong>Mesh Point</strong><strong>（</strong><strong>MP</strong><strong>）</strong>：此裝置負責了路由及資料轉發的功能，在同一個網狀網路基本服務組（Mesh Basic Service Set，簡稱MBSS）下，MP之間可以直接通信。</span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">3.<span style="line-height: normal;">&nbsp; &nbsp;&nbsp;</span><strong>Mesh Access Point</strong><strong>（</strong><strong>MAP</strong><strong>）</strong>：MAP負責與傳統的網路設備連接，並將資料轉送到MP，扮演MBSS與一般基本服務組（Basis Service Set，簡稱BSS）的中介橋梁。</span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">802.11s RMAODV路由協議使用了三種路由訊息封包，分別為路徑要求（Path Request，簡稱PREQ）、路徑回覆（Path Reply，簡稱PREP）、路徑錯誤（Path Error，簡稱PERR）[10][12]。</span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">其路由建立的步驟如下圖：</span></p>
<p style="text-indent: 24pt; line-height: 150%; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></p>
<p style="text-indent: 24pt; line-height: 150%; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">&nbsp;<img decoding="async" class=" size-full wp-image-27" src="http://codeant.cc/wp-content/uploads/2013/07/images_phocagallery_Network_80211s-rmaodv-step.jpg" alt="80211s-rmaodv-step" width="549" height="395" style="display: block; margin-left: auto; margin-right: auto;" srcset="http://codeant.cc/wp-content/uploads/2013/07/images_phocagallery_Network_80211s-rmaodv-step.jpg 549w, http://codeant.cc/wp-content/uploads/2013/07/images_phocagallery_Network_80211s-rmaodv-step-300x216.jpg 300w" sizes="(max-width: 549px) 100vw, 549px" /></span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">1. &nbsp; &nbsp;當發送端（Source）需要傳送資料時，以廣播的方式送出PREQ封包。</span><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">2.<span style="line-height: normal;">&nbsp; &nbsp;&nbsp;</span>鄰近節點收到發送端的PREQ封包後，進行再廣播（Re-Broadcast），藉此傳遞PREQ封包到達目的端（Destination）。</span><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">3.<span style="line-height: normal;">&nbsp; &nbsp;&nbsp;</span>目的端收到PREQ封包後，以單點直播（Unicast）的方式回覆PREP封包。</span><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">4.<span style="line-height: normal;">&nbsp; &nbsp;&nbsp;</span>PREP封包傳遞過程中，每一個節點都會選擇最佳的下一跳節點進行轉發，而收到PREP封包的節點會選擇將PREP封包傳送過來的節點作為到達目的端的路徑。</span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">5.<span style="line-height: normal;">&nbsp; &nbsp;&nbsp;</span>當發送端收到PREP封包後，路由資訊即建立完成，這樣由目的端往來源端方向確認路由的方式，也稱為反向路由（Reverse routing）。</span><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">6.<span style="line-height: normal;">&nbsp; &nbsp;&nbsp;</span>當發送端發現路由出現錯誤時，會以廣播的方式送出PERR封包，鄰近節點進行再廣播，通知各節點刪除現有的路由資訊，並回到第1步驟重新建立路由。</span><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;"></span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">&nbsp; &nbsp; &nbsp; &nbsp;</span></p>
<p style="font-size: 16px; line-height: 26px; text-align: left; text-indent: 24pt;"><span style="font-family: 'comic sans ms', sans-serif; font-size: 12pt;">&nbsp; &nbsp; &nbsp; &nbsp;802.11s RMAODV透過下面算式進行路徑選擇，其中Ca為連線品質，O為額外時間，Bt為訊框長度，r為傳輸速率（transmission rate），ef為訊框（frame）傳輸的錯誤率。Ca值越小代表路徑品質越好，算式中r與ef，反應了節點間的無線訊號品質，當訊號品質下降，會導致ef值上升及r值下降。</span></p>
<p style="margin-left: 24.1pt; text-indent: -24.1pt; line-height: 150%; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif;"><span style="font-size: 12pt;"></span></span></p>
<p style="margin-left: 24.1pt; text-indent: -24.1pt; line-height: 150%; text-align: center;"><span style="font-family: 標楷體;"><span style="font-size: 12pt; font-family: 標楷體;"><img loading="lazy" decoding="async" class=" size-full wp-image-28" src="http://codeant.cc/wp-content/uploads/2013/07/images_phocagallery_Network_80211s-cost.jpg" alt="80211s-cost" width="140" height="63" /></span></span></p>
<p style="text-align: justify; text-indent: 24pt; line-height: 150%;"><span style="font-family: 標楷體;"></span></p>
<p style="text-align: justify; text-indent: 24pt; line-height: 150%;"><span style="font-size: 12pt; font-family: 標楷體;"></span></p>
<p><a class="a2a_button_facebook" href="https://www.addtoany.com/add_to/facebook?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F29&amp;linkname=802.11s%20RMAODV%20%E8%A2%AB%E5%8B%95%E5%BC%8F%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%28Mesh%20Routing%20Protocol%29" title="Facebook" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_line" href="https://www.addtoany.com/add_to/line?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F29&amp;linkname=802.11s%20RMAODV%20%E8%A2%AB%E5%8B%95%E5%BC%8F%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%28Mesh%20Routing%20Protocol%29" title="Line" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_wechat" href="https://www.addtoany.com/add_to/wechat?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F29&amp;linkname=802.11s%20RMAODV%20%E8%A2%AB%E5%8B%95%E5%BC%8F%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%28Mesh%20Routing%20Protocol%29" title="WeChat" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_sina_weibo" href="https://www.addtoany.com/add_to/sina_weibo?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F29&amp;linkname=802.11s%20RMAODV%20%E8%A2%AB%E5%8B%95%E5%BC%8F%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%28Mesh%20Routing%20Protocol%29" title="Sina Weibo" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_qzone" href="https://www.addtoany.com/add_to/qzone?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F29&amp;linkname=802.11s%20RMAODV%20%E8%A2%AB%E5%8B%95%E5%BC%8F%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%28Mesh%20Routing%20Protocol%29" title="Qzone" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_linkedin" href="https://www.addtoany.com/add_to/linkedin?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F29&amp;linkname=802.11s%20RMAODV%20%E8%A2%AB%E5%8B%95%E5%BC%8F%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%28Mesh%20Routing%20Protocol%29" title="LinkedIn" rel="nofollow noopener" target="_blank"></a><a class="a2a_dd addtoany_share_save addtoany_share" href="https://www.addtoany.com/share#url=http%3A%2F%2Fcodeant.cc%2Farchives%2F29&#038;title=802.11s%20RMAODV%20%E8%A2%AB%E5%8B%95%E5%BC%8F%E8%B7%AF%E7%94%B1%E5%8D%94%E8%AD%B0%28Mesh%20Routing%20Protocol%29" data-a2a-url="http://codeant.cc/archives/29" data-a2a-title="802.11s RMAODV 被動式路由協議(Mesh Routing Protocol)"></a></p><p>這篇文章 <a href="http://codeant.cc/archives/29">802.11s RMAODV 被動式路由協議(Mesh Routing Protocol)</a> 最早出現於 <a href="http://codeant.cc">碼蟻創研工坊 - CODEANT STUDIOS</a>。</p>
]]></content:encoded>
					
		
		
			</item>
		<item>
		<title>淺談無線自組網的效能關鍵 &#8211; 路徑選擇(Path Selection)</title>
		<link>http://codeant.cc/archives/23</link>
		
		<dc:creator><![CDATA[codeant]]></dc:creator>
		<pubDate>Wed, 10 Jul 2013 21:49:46 +0000</pubDate>
				<category><![CDATA[Netowrk]]></category>
		<category><![CDATA[無線]]></category>
		<category><![CDATA[自組網]]></category>
		<category><![CDATA[路徑選擇]]></category>
		<category><![CDATA[路由協議]]></category>
		<guid isPermaLink="false">http://codeant.cc/2013/07/11/mesh-routing-path-selection/</guid>

					<description><![CDATA[<p>&#160; &#160; 在無線自組網(WMNs或是MANETs)中，有許多因素可以牽動網狀路由協議的效能表 [&#8230;]</p>
<p>這篇文章 <a href="http://codeant.cc/archives/23">淺談無線自組網的效能關鍵 &#8211; 路徑選擇(Path Selection)</a> 最早出現於 <a href="http://codeant.cc">碼蟻創研工坊 - CODEANT STUDIOS</a>。</p>
]]></description>
										<content:encoded><![CDATA[<p style="text-align: left;"><span style="font-size: 16px; line-height: 26px;"><span style="font-size: 12pt;">&nbsp; &nbsp; 在無線自組網(</span><span style="font-size: 12pt;">WMNs</span><span style="font-size: 12pt;">或是</span><span style="font-size: 12pt;">MANETs)</span><span style="font-size: 12pt;">中，有許多因素可以牽動網狀路由協議的效能表現，而路徑選擇的正確與否，是影響最後效能表現的重要因素。</span></span></p>
<p>  <span id="more-23"></span>  </p>
<div style="font-size: 16px; line-height: 26px; text-align: left;">
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-family: 'comic sans ms', sans-serif;"><span style="font-size: 12pt;">&nbsp; &nbsp; 路徑選擇是網狀路由協議的一個評價指標，在</span><span style="font-size: 12pt;">無線自組網</span><span style="font-size: 12pt;">的架構下，傳輸路徑必須跟隨當前環境做出適當的變化，一個優秀的網狀路由協議必須可以發現更好的路徑並且採用，也能避免誤用較差的路徑。</span></span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-size: 12pt; font-family: 'comic sans ms', sans-serif;"></span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-size: 12pt; font-family: 'comic sans ms', sans-serif;">&nbsp; &nbsp; 針對路徑選擇的效能評價，可以二個項目為主：</span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-size: 12pt; font-family: 'comic sans ms', sans-serif;">一是出現更好路徑後，更正到較佳路徑的反應時間；</span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-size: 12pt; font-family: 'comic sans ms', sans-serif;">二是路徑選擇的正確率，也就是受測的路由協議能否選定最佳路徑。</span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-size: 12pt; font-family: 'comic sans ms', sans-serif;"></span></div>
<div style="font-size: 16px; line-height: 26px; text-align: left;"><span style="font-size: 12pt; font-family: 'comic sans ms', sans-serif;">&nbsp; &nbsp; 至於如何搭建一個多路徑的測試環境用以量測網狀路由協議在路徑選擇上的效能，並進行分析與比較。我想，那就是另外一個議題了。</span></div>
</p></div>
<p><a class="a2a_button_facebook" href="https://www.addtoany.com/add_to/facebook?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F23&amp;linkname=%E6%B7%BA%E8%AB%87%E7%84%A1%E7%B7%9A%E8%87%AA%E7%B5%84%E7%B6%B2%E7%9A%84%E6%95%88%E8%83%BD%E9%97%9C%E9%8D%B5%20%E2%80%93%20%E8%B7%AF%E5%BE%91%E9%81%B8%E6%93%87%28Path%20Selection%29" title="Facebook" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_line" href="https://www.addtoany.com/add_to/line?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F23&amp;linkname=%E6%B7%BA%E8%AB%87%E7%84%A1%E7%B7%9A%E8%87%AA%E7%B5%84%E7%B6%B2%E7%9A%84%E6%95%88%E8%83%BD%E9%97%9C%E9%8D%B5%20%E2%80%93%20%E8%B7%AF%E5%BE%91%E9%81%B8%E6%93%87%28Path%20Selection%29" title="Line" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_wechat" href="https://www.addtoany.com/add_to/wechat?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F23&amp;linkname=%E6%B7%BA%E8%AB%87%E7%84%A1%E7%B7%9A%E8%87%AA%E7%B5%84%E7%B6%B2%E7%9A%84%E6%95%88%E8%83%BD%E9%97%9C%E9%8D%B5%20%E2%80%93%20%E8%B7%AF%E5%BE%91%E9%81%B8%E6%93%87%28Path%20Selection%29" title="WeChat" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_sina_weibo" href="https://www.addtoany.com/add_to/sina_weibo?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F23&amp;linkname=%E6%B7%BA%E8%AB%87%E7%84%A1%E7%B7%9A%E8%87%AA%E7%B5%84%E7%B6%B2%E7%9A%84%E6%95%88%E8%83%BD%E9%97%9C%E9%8D%B5%20%E2%80%93%20%E8%B7%AF%E5%BE%91%E9%81%B8%E6%93%87%28Path%20Selection%29" title="Sina Weibo" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_qzone" href="https://www.addtoany.com/add_to/qzone?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F23&amp;linkname=%E6%B7%BA%E8%AB%87%E7%84%A1%E7%B7%9A%E8%87%AA%E7%B5%84%E7%B6%B2%E7%9A%84%E6%95%88%E8%83%BD%E9%97%9C%E9%8D%B5%20%E2%80%93%20%E8%B7%AF%E5%BE%91%E9%81%B8%E6%93%87%28Path%20Selection%29" title="Qzone" rel="nofollow noopener" target="_blank"></a><a class="a2a_button_linkedin" href="https://www.addtoany.com/add_to/linkedin?linkurl=http%3A%2F%2Fcodeant.cc%2Farchives%2F23&amp;linkname=%E6%B7%BA%E8%AB%87%E7%84%A1%E7%B7%9A%E8%87%AA%E7%B5%84%E7%B6%B2%E7%9A%84%E6%95%88%E8%83%BD%E9%97%9C%E9%8D%B5%20%E2%80%93%20%E8%B7%AF%E5%BE%91%E9%81%B8%E6%93%87%28Path%20Selection%29" title="LinkedIn" rel="nofollow noopener" target="_blank"></a><a class="a2a_dd addtoany_share_save addtoany_share" href="https://www.addtoany.com/share#url=http%3A%2F%2Fcodeant.cc%2Farchives%2F23&#038;title=%E6%B7%BA%E8%AB%87%E7%84%A1%E7%B7%9A%E8%87%AA%E7%B5%84%E7%B6%B2%E7%9A%84%E6%95%88%E8%83%BD%E9%97%9C%E9%8D%B5%20%E2%80%93%20%E8%B7%AF%E5%BE%91%E9%81%B8%E6%93%87%28Path%20Selection%29" data-a2a-url="http://codeant.cc/archives/23" data-a2a-title="淺談無線自組網的效能關鍵 – 路徑選擇(Path Selection)"></a></p><p>這篇文章 <a href="http://codeant.cc/archives/23">淺談無線自組網的效能關鍵 &#8211; 路徑選擇(Path Selection)</a> 最早出現於 <a href="http://codeant.cc">碼蟻創研工坊 - CODEANT STUDIOS</a>。</p>
]]></content:encoded>
					
		
		
			</item>
	</channel>
</rss>
