December 2002
Intermediate to advanced
576 pages
16h 39m
English
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7.5. Ethernet in the First Mile (EFM)
Figure 7.27 shows the basic concept of EFM [34]. One, two or four phone lines may be coordinated to deliver 10 or 100 Mbps symmetric VDSL service in EFM. Even though “Ethernet” physical-layer copper twisted-pair standards have long been established, they are restricted to a length of 100 meters for 10 Mbps (“10BT”), 100 Mbps (“100BT”) and 1000 Mbps (“1000BT”). Each uses a category-5, 5e, or 6 set of four twisted pairs in synchronous point-to-point transmission. Longer-length transmission fundamentally requires a different physical-layer modulation, while the upper layer “Ethernet/TCP/IP” functionality can be maintained so that the DSL line essentially looks like a “long-range Ethernet.” The current physical-layer ...
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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