ActiveEthernet

1、Brief introduction POE (Power Over Ethernet) refers to the existing Ethernet cabling infrastructure Cat.5 do not make any changes to the case, for a number of IP-based terminals (such as IP telephones, wireless LAN access point AP, network cameras etc.) to transmit data signals at the same time , bu

2、t also to provide DC power supply such equipment technology . POE technology to ensure the normal operation of the existing network to ensure the safety of the existing structured cabling while minimizing costs+. PoE is also known as LAN-based power supply system (PoL, Power over LAN) or Active Ethe

3、rnet (Active Ethernet), sometimes referred to as Power over Ethernet , which is using the existing transmission standard Ethernet cable to simultaneously transmit data and the latest standard specification of electric power , and to maintain compatibility with existing Ethernet system and user . IEE

4、E 802.3af standard is based on the new standard Ethernet POE power supply system , which increases the relevant standard power supply via the network cable directly on the basis of IEEE 802.3 , the expansion of the existing Ethernet standards , is the first international on power distribution standa

5、rds.+ + work process+ When PSE supply terminal device arranged in a network , POE Power over Ethernet working process is as follows. +1. Detection A beginning , PSE equipment in the port output low voltage cable terminal until it detects a connection to a support IEEE 802.3af standard powered end de

6、vices.+ 2. PD Premises Equipment Category When the receiving end device detects the PD , PSE device may be classified as a PD , and PD devices needed to assess this power loss.+ 3. Start Power In a configurable time ( generally less than 15s) start period , PSE equipment starting from a low voltage

7、power supply to the PD device , providing up to 48V DC power supply. +4. Power Supply To provide a stable and reliable 48V DC to PD device , the device does not meet the PD across 15.4W power consumption. +5. off If the PD device is disconnected from the network , PSE will quickly ( generally within

8、 300 400ms of ) stopping power for the PD device , and repeat the detection process to detect the cable terminal is connected PD devices.+ + Leveraging the ubiquity of standard Ethernet and IP technologies, an active Ethernet network installs the associated network electronics at the subscriber netw

9、ork edge instead of the CO or head-end. Such devices can be configured to be deployed on a pole, vault, fiber strand or even in an MTU/MDU basement. While the cost per subscriber in a PON-based network becomes more economical with more subscribers, a standard OLT (optical line terminal) can only sup

10、port up to 32 subscribers in a serving area. This means that to serve one more customer, a carrier has to bear the expense of another OLT. Alternatively, an active network can run over longer distances and can be built out on a pay-as-you-grow basis by providing each subscriber with 100 Mbps to 1 Gb

11、ps of dedicated bandwidth.+ +PON and Active Ethernet AdvantagesPON is more flexible+Optical network can be point-to-point or split in the field+Outside plant architecture can be active or passive+Standard supports legacy services : RF video and TDM+Can be deployed in areas with limited fiber cable o

12、r conduit+Consumes much less CO space and 1/3 as much power at the CO +Supports TDM based T1s required for delay and latency sensitive servicesAE is better suited to business+Fiber network is dedicated point-to-point+Better suited for very high bit rate service (100mbs+) to medium and large business

13、es , ultra broadband residential+Optical reach 40 km and beyond+Layer 2 only model favored by businesses+ubiquity+n. 普遍存在；到處存在+If experiments show the road is short and easy then it would be a strong argument for the ubiquity of life in space. +如果實(shí)驗(yàn)表明這是很容易簡便的，它將成為“宇宙中生命是普遍存在的”最有力的證據(jù)。+Today, confront

14、ed with the ubiquity of the internet, we need a whole new set of skills to navigate the information-laden environment we inhabit. +今天，面對著無處不在的互聯(lián)網(wǎng)，我們需要一整套新的技術(shù)為我們在我們所棲居的這個(gè)滿載信息的環(huán)境中導(dǎo)航。+vault +n. 拱頂；撐竿跳；地下室+vi. 跳躍；成穹狀彎曲+vt. 做成圓拱形；撐竿跳過+pole vault 撐竿跳高 ; 撐桿跳高 ; 撐桿跳 ; 撐桿跳高+But a year later, at the world cha

15、mpionships in Australia, she won a gold medal on the vault and signaled her dominance of the apparatus. +然而一年以后的澳大利亞世錦賽上，程菲在跳馬項(xiàng)目上摘取了金牌，并開始宣稱自己在該項(xiàng)目上的統(tǒng)治地位。+Extrapolating current trends, some forecasters predict that Chinas economy will vault ahead of Americas in 15 years. +一些預(yù)言家根據(jù)目前的趨勢推斷，中國經(jīng)濟(jì)將在未來的15年來跳躍到美國的前面去。+str