【正文】 制造商協(xié)會(huì)額定 的范圍內(nèi)，那么什么都不需要變的。這部分歸結(jié)于制造商的可觀的營(yíng)銷炒作。 總結(jié) 高規(guī)格的 銅布線在數(shù)據(jù)網(wǎng)絡(luò)（ 6或 7類）中所提供的好處很可能是有限的，短暫的。 網(wǎng)絡(luò)的單調(diào)上升 1980年以來(lái)的數(shù)據(jù)傳輸速率，當(dāng)網(wǎng)絡(luò)速度被由（ clunkety 彈響電傳打字機(jī)）機(jī)械轉(zhuǎn)速機(jī)制決定時(shí)，網(wǎng)絡(luò)已經(jīng)看到了數(shù)據(jù)傳輸速率的單調(diào)上升。 這種建筑物局部區(qū)域網(wǎng)絡(luò)（ LAN）是關(guān)鍵業(yè)務(wù)的一部分 ，但是幸運(yùn)地，它是相對(duì)地容易對(duì)它做變動(dòng)的。當(dāng)使用 50/125μ m 光纖時(shí)，可以增加至約 500米。 水平局域網(wǎng) 當(dāng)考慮建筑物內(nèi)的“水平”分布時(shí)，正如“摩爾定律”預(yù)測(cè)的那樣，我們看到了在數(shù) 據(jù)傳輸速率上同樣的增長(zhǎng)，顯示出了近期的加速趨勢(shì)，但還是落后垂直數(shù)據(jù)速率 5年。不同于建筑物的垂直局域網(wǎng) ,水平網(wǎng)絡(luò)的升級(jí)是非常昂貴。提供電源、音頻 /數(shù)據(jù)線纜所采取的處理必須控制在足夠并且美觀程度上。這將允許在建筑物內(nèi)使用現(xiàn)有的、低等級(jí)的 3類電話線纜。事實(shí)上 ,有人說(shuō)，在鐵絲網(wǎng)上，你接收和發(fā)送數(shù)據(jù)的速率在誤差率接受的范圍內(nèi)可以達(dá)到吉比特位 /秒。 相對(duì)較大的外部串?dāng)_影響著弱信號(hào) ,尤其是在線纜末端附近。在連接器上 ,相對(duì)高功率的信號(hào) 被 發(fā)射 進(jìn) 非?？拷?到 接收的電纜 ,沿著電纜長(zhǎng)度輻射損失已經(jīng)開(kāi)始減弱。 現(xiàn)在已經(jīng)開(kāi)始開(kāi)發(fā) 6類線纜，以便解決其中一些問(wèn)題，但是，目前，還沒(méi)有批準(zhǔn)任何標(biāo)準(zhǔn)。 這個(gè)暫緩的過(guò)程很有可能是短的。 這必將是一個(gè)非常殘酷的限制。擴(kuò)展帶寬多模光纖和VCSEL 激光器的發(fā)展已經(jīng)促使光學(xué)技術(shù)改進(jìn)。擴(kuò)展帶寬多模光纖，已經(jīng)制定了一個(gè)改進(jìn)的折射率分布。這可能發(fā)生在 Gbs 速率。通過(guò)對(duì)比的方式， PC 機(jī)的壽命約為 2 3年，而以太交換機(jī) 3 5年。 對(duì)于 1 Gbs 工作，銅 5e 類電纜是必需的。如果因?yàn)槟壳暗某杀締?wèn)題，在任何給定的項(xiàng)目并不實(shí)際安裝光纖，但至少，在布線內(nèi)容中應(yīng)該預(yù)留光纖的空間，以適應(yīng)未來(lái)的應(yīng)用。這具有下列優(yōu)點(diǎn)： 對(duì)裝修有最小的干擾； 對(duì)大廈的員工正常工作模式有最小的干擾。它是由預(yù)安裝管道保護(hù)的免受損壞。 輸送管道是小的，并且 可以通過(guò)傳統(tǒng)的線纜包含進(jìn)行運(yùn)載 。 外文原文： The Future of Structured Cabling The JHMI Premise Distribution Plan will be consistent with standards specified by the ATamp。T type D unshielded twisted pairs shall be used. Each voice/data wall station will receive four type D cables. Each 4pair D cable will be terminated in an standard RJ45 (8position) jack so that each wallplate will need to house four RJ45 jacks. Vertical Distribution Wire amp。s when work speeds were dictated by the rotor speed of mechanical mechanisms (clunketyclunk teletypes), the works have seen a monotonous rise in data rates. The rise has followed Moore39。 it is just a matter of time before we start receiving demands for gigabit working at the desktop. High bandwidth/critical bit rate applications such as VOIP, video streaming, video conferencing and puter aided design (CAD), are being mon. Unlike the building39。s properties to fluctuations in increasing loss of signal strength at high data rates due to its radiation from the cable. The relatively large effects of external interference on weak signals, particularly near the ends of the cable. This is especially important where data cables share adjacent cable containment with mains wiring. The increased signal coupling between pairs of conductors in the same cable (crosstalk). This situation is exacerbated at the ends of the cable where it is attached to the hardware. At the connector, relatively high power transmit signals are launched into the cable in very close proximity to the receive signals that have already been attenuated by radiation loss along the cable39。s staff. The extra bandwidth that fibre offers can be provided on a piecemeal basis and in parallel with existing wiring when need or budget permits. It allows expenditure to be deferred. Blown fibre is raw fibre (about diameter). It is protected from damage by the preinstalled conduits. It is cheaper than traditional fibre cable where fibres are encased in the familiar plastic sheath. The grade of fibre can be changed if circumstances change or if damage occurs. Old fibres can be quickly and easily withdrawn and replaced by different ones. Conduits are small and can be carried by traditional cable containment. Damaged conduit can be repaired by cutting out and the damaged section and replacing it with new tube. As fibre has all the advantages of proven technology, far superior immunity to electrical noise, intrinsic electrical safety, superior bandwidth capability, a high degree of data security and the ability to carry signals over long distances permitting the use of collapsed backbone topologies, its use or potential use ought to be seriously considered for all new cable installations. If history teaches us anything, it39。D to be worthwhile. Worst case predictions for category 7 at 10gigabit speeds imply a length restriction of about 25m. This would be a severe limitation. Any improvement will be at the expense of costlier transceivers. In any event, these distance constraints at higher data rates are onerous for UTP cabling. Category 7 then, must be at least a fibre solution? O