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<p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">综合布线标准是和万兆以太网的网络技术标准同步进行的，<span lang="EN-US">IEEE(</span>国际电子与电气工程师协会<span lang="EN-US">)</span>负责制定万兆以太网网络物理层技术标准，<span lang="EN-US">TIA(</span>美国通信工业委员会<span lang="EN-US">)</span>以及<span lang="EN-US">ISO(</span>国际标准化委员会<span lang="EN-US">)</span>分别负责制定北美以及国际的万兆以太网布线铜缆技术标准。<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">早在<span lang="EN-US">2002</span>年<span lang="EN-US">6</span>月，<span lang="EN-US">IEEE802.3ae</span>任务小组就颁布了一系列基于光纤的万兆以太网的标准<span lang="EN-US">,</span>能够支持万兆传输的距离在<span lang="EN-US">300m(10GBase-SR,OM3</span>多模光纤<span lang="EN-US">)</span>到<span lang="EN-US">40Km(10GBase-EW</span>，<span lang="EN-US">OS1</span>单模光纤<span lang="EN-US">)</span>之间<span lang="EN-US">,</span>该技术适用于距离较远的园区主干或数据传输速率要求较高的楼内垂直主干以及数据中心服务器集群。然而，万兆以太网光纤解决方案不论从网络设备成本、安装成本还是维护成本各个方面都远远高于采用双绞线传输万兆的解决方案。<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">对于双绞线传输万兆的标准，<span lang="EN-US">TIA/EIA TR-42.7</span>子委员会及其与<span lang="EN-US">IEEE</span>协调委员会是于<chsdate wst="on" isrocdate="False" islunardate="False" day="28" month="7" year="2007"><span lang="EN-US">2007</span>年<span lang="EN-US">7</span>月<span lang="EN-US">28</span>日</chsdate>发布了<span lang="EN-US">TIA/EIA 568B.2-10</span>最新的第五份草案，作为附录<span lang="EN-US">10</span>放入<span lang="EN-US">TIA/EIA568B.2</span>标准。该草案针对<span lang="EN-US">IEEE802.3an 10Gbase-T</span>的<chmetcnv wst="on" tcsc="0" numbertype="1" negative="False" hasspace="False" sourcevalue="100" unitname="米"><span lang="EN-US">100</span>米</chmetcnv>传输距离及<span lang="EN-US">500MHZ</span>带宽要求定义了一套全新的增强型六类<span lang="EN-US">(Cat<chmetcnv wst="on" tcsc="0" numbertype="1" negative="False" hasspace="False" sourcevalue="6" unitname="a">6A</chmetcnv>)</span>布线系统包括连接器件、线缆、跳线技术性能标准以及现场测试<span lang="EN-US">ANEXT</span>的方法，其中关于测试插头回波损耗、非平衡直流电阻等技术参数有待进一步确定。<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">经过又一轮的认真论证和投票，<span lang="EN-US">TIA TR42</span>工程委员会终于于<chsdate wst="on" isrocdate="False" islunardate="False" day="8" month="2" year="2008"><span lang="EN-US">2008</span>年<span lang="EN-US">2</span>月<span lang="EN-US">8</span>日</chsdate>批准颁布<span lang="EN-US">TIA <chmetcnv wst="on" tcsc="0" numbertype="1" negative="False" hasspace="False" sourcevalue="6" unitname="a">6A</chmetcnv></span>标准（<span lang="EN-US">TIA 568 B.2-10</span>） ，其代表了<span lang="EN-US">500MHz</span>定义下网络电缆要求的高级设置。<chmetcnv wst="on" tcsc="0" numbertype="1" negative="False" hasspace="False" sourcevalue="6" unitname="a"><span lang="EN-US">6A</span></chmetcnv>标准与先前的标准完全兼容，包括<span lang="EN-US">Category 6, Category 5e </span>和<span lang="EN-US">Category 5.<p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">随着<span lang="EN-US">TIA <chmetcnv wst="on" tcsc="0" numbertype="1" negative="False" hasspace="False" sourcevalue="6" unitname="a">6A</chmetcnv></span>标准（<span lang="EN-US">TIA 568 B.2-10</span>）的正式颁布，对于用户来说真正关注的是：最新的万兆以太网布线铜缆技术标准到底有什么新的亮点，它对布线用户有什么意义，以前的测试方法是否会为此改变，在安装上又要注意什么呢？<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span style="FONT-SIZE: 12pt; COLOR: blue; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">带着这些问题，综合布线工作组组织了一些有关<span lang="EN-US">6A</span>标准的问题进行讨论，希望通过这些讨论能够抛砖引玉，请大家共同来探讨、分析。<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-line-height-rule: exactly;"><b style="mso-bidi-font-weight: normal;"><span lang="EN-US" style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">1</span></b><b style="mso-bidi-font-weight: normal;"><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">．<span lang="EN-US">TIA/EIA568-B.2-10</span>标准制定的意义？<span lang="EN-US"><p></p></span></span></b></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span lang="EN-US" style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">568-B.2-10</span><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">的目标是定义一个新的“扩展六类”标准，包含布线部件和系统的规格指标和测试程序，以支持<chmetcnv wst="on" tcsc="0" numbertype="1" negative="False" hasspace="False" sourcevalue="100" unitname="米"><span lang="EN-US">100</span>米</chmetcnv><span lang="EN-US">4</span>个连接点的<span lang="EN-US">10GBASE-T</span>平衡双绞线传输。此标准同样把带宽定义在<span lang="EN-US">500MHz</span>但是与<span lang="EN-US">TSB-155</span>相比，提出了更高的性能要求，如外部串扰和插入损耗余量等。此标准预计会先于<span lang="EN-US">IEEE802.3an<span style="mso-spacerun: yes;"> </span>10GBASE-T</span>标准发布。<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-line-height-rule: exactly;"><b style="mso-bidi-font-weight: normal;"><span lang="EN-US" style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">2</span></b><b style="mso-bidi-font-weight: normal;"><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">．在面向<chmetcnv wst="on" tcsc="0" numbertype="1" negative="False" hasspace="False" sourcevalue="10" unitname="g"><span lang="EN-US">10G</span></chmetcnv>的<chmetcnv wst="on" tcsc="0" numbertype="1" negative="False" hasspace="False" sourcevalue="6" unitname="a"><span lang="EN-US">6A</span></chmetcnv>解决方案中，屏蔽产品有何优势？<span lang="EN-US"><p></p></span></span></b></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">大家都知道在高带宽应用如<span lang="EN-US">10GBASE-T</span>的场合中，由于平衡绞和线对结构的双绞线而带来外部串扰是影响系统性能的新课题。非屏蔽的布线系统虽然可以抵御一定的外界干扰，但工程中同一线槽内的双绞线一般均为同厂家产品，这些线缆完全一样，在传输高速网络信号时，相邻的线缆间会产生信号的相互耦合，尤其是相同颜色的线对由于绞距与方向完全一样，耦合的干扰无法依靠平衡结构抵消。<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">屏蔽双绞线铝箔内的线对也是精密的双绞结构，但它们已经不承担抵抗干扰的主要作用，接地的铝箔对电磁信号具有非常优异反射、吸收、隔离的性能，它使传输数据的双绞导线与外界的电磁环境完全隔离。屏蔽布线的屏蔽结构使得它对降低线缆间的相互干扰有先天的优势，不仅可以屏蔽外界的电磁信号，铝箔也同时阻断了线缆本身的电磁泄露，不会发射干扰信号影响其它线缆的工作。紧密线槽内部的各个线缆同时运行万兆以太网，相互间没有影响。<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">一般采用耦合衰减来衡量线缆抵抗干扰的能力。屏蔽系统一般比同级别非屏蔽系统至少高<span lang="EN-US">20dB</span>左右。<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">屏蔽系统具有比非屏蔽系统更大的可用带宽，一般传输万兆以太网的最低要求布线系统至少具有<span lang="EN-US">15.9Gb/s</span>（过去为<span lang="EN-US">18Gb/s</span>）的物理层信道传输能力，非屏蔽的万兆布线系统物理层的传输能力为<span lang="EN-US">17</span>～<span lang="EN-US">20GBps</span>，余量不是很大，屏蔽的万兆布线系统则可以达到<span lang="EN-US">35GBps</span>以上的传输能力。<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-line-height-rule: exactly;"><b style="mso-bidi-font-weight: normal;"><span lang="EN-US" style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">3</span></b><b style="mso-bidi-font-weight: normal;"><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">．为什么<span lang="EN-US">TIA</span>把支持<span lang="EN-US">10GBASE-T</span>的<chmetcnv wst="on" tcsc="0" numbertype="1" negative="False" hasspace="False" sourcevalue="6" unitname="a"><span lang="EN-US">6A</span></chmetcnv>标准从<span lang="EN-US">625MHz</span>降低到<span lang="EN-US">500MHz</span>？<span lang="EN-US"><p></p></span></span></b></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span lang="EN-US" style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">IEEE802.3an</span><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">工作组最早对<span lang="EN-US">10GBASE-T</span>物理层的脉冲振幅调制编码方式定义沿用了<span lang="EN-US">1000GABSE-T</span>的<span lang="EN-US">PAM5</span>编码。<span lang="EN-US">PAM5</span>采用<span lang="EN-US">5</span>种不同的信号电平编码来代替简单的二进制编码，可以达到很好的带宽利用。基本<span lang="EN-US">PAM5</span>的<span lang="EN-US">10GBASE-T</span>对布线带宽的需求是<span lang="EN-US">625MHz</span>。<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span lang="EN-US" style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">2004</span><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">年<span lang="EN-US">6</span>月召开的<span lang="EN-US">IEEE802.3an</span>工作组会议上，为了提高系统的噪声免疫力和减少收发器的复杂程度，把编码方式修改为<span lang="EN-US">PAM8</span>，支持<span lang="EN-US">833Mbaud</span>波特率和<span lang="EN-US">400MHz</span>带宽，对布线系统的带宽要求也相应地修改为<span lang="EN-US">500MHz</span>，采用<span lang="EN-US">LDPC</span>编码所需的夏农信道容量也下降到<span lang="EN-US">15.9Gb/s</span>。<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt 0.1pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-line-height-rule: exactly; mso-para-margin-left: .1pt;"><b style="mso-bidi-font-weight: normal;"><span lang="EN-US" style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">4</span></b><b style="mso-bidi-font-weight: normal;"><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">．外部串扰参数如何测试？<span lang="EN-US"><p></p></span></span></b></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">目前测试仪厂商正在研究现场测试安装系统<span lang="EN-US">ANEXT</span>的方法。但是在实验室里已经可以实现线缆的外部串扰性能测试，最差情况是<span lang="EN-US">6</span>根<span lang="EN-US">4</span>对线缆包裹一根被测<span lang="EN-US">4</span>对线缆，典型情况可以测试两根相邻<span lang="EN-US">4</span>对线缆的外部串扰，此方法也可以用于链路或信道的测试。<span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;">虽然现场无法测试链路或信道的外部串扰性能，但是线缆和连接硬件在设计上已经最大化的考虑了<span lang="EN-US">ANEXT</span>的余量，如配线架和工作区插座安装时的间隔空间等，而且在敷设线缆的过程中的随意性和线缆捆绑的新法则也避免了过量串扰的引入。同时，<span lang="EN-US">10G</span>设备厂商们也在考虑把<span lang="EN-US">ANEXT</span>评估能力加入他们的设计中。</span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;"><span lang="EN-US"><p></p></span></span></p><p class="MsoNormal" align="left" style="BACKGROUND: white; MARGIN: 7.8pt 0cm 0pt; TEXT-INDENT: 20.5pt; LINE-HEIGHT: 20pt; TEXT-ALIGN: left; mso-pagination: widow-orphan; mso-margin-bottom-alt: auto; mso-para-margin-top: .5gd; mso-char-indent-count: 1.71; mso-line-height-rule: exactly;"><span style="FONT-SIZE: 12pt; COLOR: #474747; FONT-FAMILY: 宋体; mso-font-kerning: 0pt; mso-bidi-font-family: Arial;"><span lang="EN-US"><p>更多内容请见：<a href="http://blog.sina.com.cn/cablingsystem">http://blog.sina.com.cn/cablingsystem</a></p></span></span></p> |
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