标题: 电信英语翻译，请指正 [打印本页] 作者: swtrunk 时间: 2004-9-30 13:35 标题: 电信英语翻译，请指正 100Base-T100 Mbps, Baseband, Twisted pair. In sort, 100Base-T is a 100 Mbps LAN (Local Area Network) standard known by the generic name of Fast Ethernet, and running over UTP (Unshielded Twisted Pair) copper cable. There are three basic implementations of Fast Ethernet — 100Base-FX, 100Base-T and 100Base-T4. Each specification is identical except for its interface circuitry, which determines on what type of cabled medium it runs. As a result, the technologies currently aren't interchangeable; each must be connected to its own type of hub. For example, a 100Base-T4 NIC must be connected to a 100Base-T4 interface; likewise, a TX NIC must be connected to a TX interface at the other end. 100Base-T is the most popular and cost-effective high-speed LAN technology because it is designed to integrate with existing Ethernets with minimal disruption, as all are based on the conventional Ethernet MAC (Media Access Control) standard. Essentially an extension of 10Base-T, 100Base-T achieves increased throughput by decreasing the latency period between bits, which effectively increases the packet speed by a factor of 10. The standard adheres to the 802.3u MAC specification, which builds on the 802.3 Ethernet standard to ensure compatibility with existing 10Base-T installations. As a result, an upgrade from 10Base-T to 100base-T is invisible to users, the NOS and current network management applications. 100Base-T uses the 4B5B Manchester encoding scheme for purposes of Clock/Data Recovery (CDR).
My own experience with upgrading to 100Base-T was not 100% overwhelmingly positive. First, we tried upgrading our Macintosh network to 100 Mbps (i.e., Fast Ethernet), but found zero improvement in the speed of transferring a file from the server to a Mac. Problem? Allegedly, the Macintosh network operating system simply won't work that fast. Then we started to upgrade some of our PC workstations to 100 Mbps, but found it made more sense to break our big PC LAN apart into smaller LANs, each run by an Ethernet switch and then have each Ethernet switch join to each other by 100 Mbps over fiber running 100Base-FX. That has worked wonderfully. The point of all this? Designing networks is not trivial. The speed of the individual links — 10 Mbps or 100 Mbps — may not be the gating factor. Check before you spend the money. See 4B5B, 100Base-FX, 100Base-T4, 100Base-FX, and CDR.
100Mbps，基带，双绞线。由快速以太网的常用名可知，100Base-T是100MbpsLAN（局域网）标准，运行于UTP（无屏蔽双绞线电缆）铜线电缆。共有三种基本快速以太网应用，分别是100Base-FX, 100Base-T and 100Base-T4。除了接口电路，每一种的技术规定都是相同的。主要是由网络采用何种类型的电缆介质所决定的。因此，目前各种技术标准不能相互转换。每一种必须与自己的集线器相连接。例如，100Base-T4 NIC(网络接口卡）必须与100Base-T4接口相连接；同样，TX NIC必须与另一端TX接口相连接。100Base-T是一种低成本高效率局域网技术，非常受欢迎。因为它结合现有的以太网，采用最小中断，并且所有网络技术都是建立在常规以太网MAC（介质访问控制）标准的基础上的。实际上，通过降低比特间的等待时间，以及对10Base-T和100Base-T进行扩展，从而提高了效率，成功地将分组速度提高了10倍。100Base-T标准服从802.3u MAC协议，建立在802.3以太网标准之上，从而确保与现有的10Base-T相兼容。因此，用户、NOS（Network Operating System）和目前的网络管理应用感觉不到从10Base-T到100Base-T的升级。为了实现时钟/数据恢复（CDR），100Base-T采用4B5B曼彻斯特编码。
我个人认为升级到100Base-T并不是完全正确的。首先，我们试图将麦金托什机网络升级为100Mbps（即快速以太网），但是发现文件从服务器传送到麦金托什机网络的速度并没有提高。为什么呢？据说是因为麦金托什机网络操作系统速度不够快。然后，我们开始将个人电脑工作平台的速度提高到100Mbps，但是发现将大PC机局域网拆分层一个个小局域网将更有意义，每一个小局域网通过以太网交换机彼此相连，这种解决方式非常有效。所有的设计理念就是这个吗？网络设计非常重要，无论是10Mbps还是100Mbps，单个链路的速度不是首要因素。在你准备安装以前先思考一下你需要什么。参见4B5B, 100Base-FX, 100Base-T4, 100Base-FX,以及 CDR