Ethernet Networks - Design, Implementation, Operation, Management (Fourth Edition)

Although advances in communications technology continue to occur at a rapid pace, that paraphrase continues to be valid. Within the past decade, the bandwidth of 10 Mbps Ethernet was advanced by a factor of one thousandwith the introduction of a series of enhancements to the original Ethernet specification. First, Fast Ethernet resulted in the bandwidth of Ethernet increasing by a factor of 10 to 100 Mbps. The introduction of Gigabit Ethernet resulted in another order of magnitude increase in bandwidth to 1 Gbps. Although many persons felt that a transmission capacity of 1 Gbps would be more than sufficient for the foreseeable future, another adage states that many applications will grow to use all available bandwidth. While most organizations may be hard pressed to use 1 Gbps of bandwidth, other organizations, including Internet Service Providers and corporations and universities with large backbone LANs, were able to literally fill the 1 Gbps pipe, resulting in the development of 10 Gbps Ethernet. Thus, over the past decade Ethernet’s 10 Mbps operation has increased by a factor of 1000 to 10 Gbps.

This new edition provides a significant amount of additional material to most of the chapters of this book’s previous edition. New information added includes coverage of the transmission of Gigabit over copper conductors, the evolution of cabling standards that facilitate support of higher Ethernet operating rates, and the manner by which LAN switches operate on Ethernet frames transporting information at higher layers in the Open System Interconnection Reference Model.

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Apples' ban on Flash Explained.

Steve Jobs has used an open letter to defend Apple's decision not to allow Flash on many of the firm's products.

Neither the iPod, iPhone nor iPad can run the software despite the widespread use of Flash technology on websites for video and animations.

Mr Jobs said Flash was made for an era of "PCs and mice" and performed poorly when translated to run on touchscreen smartphones and handheld devices.

He also criticised the technology for being only under the control of Adobe.
Crashing Macs

The letter comes soon after Flash creator Adobe announced it was ending its efforts to make tools that translate Flash code into programs that can run on Apple gadgets.



Adobe's announcement followed a change to the terms and conditions of the license that software developers must sign when writing code to run on Apple products.

That change banned developers from using the automatic translation tools Adobe had been developing.

Mr Jobs' lengthy open letter explains some of Apple's thinking behind the effective ban on the use of Adobe tools and translating Flash.

He said it was bad for the smartphone era because it did not support multi-touch systems and helped drain battery power unnecessarily.

The Apple boss added that it fell short on security and was "the number one reason Macs crash".

He also pointed out that there were now alternatives to flash technology, particualry for web video.

Mr Jobs also wrote about the tools that software developers use when creating applications.

The reason Apple did not want people to use Adobe's automatic translation tools, he said, was because experience had told it that it results in "sub-standard apps".

Adobe has yet to issue any response to Mr Jobs comments.

The letter provoked an avalanche of comments online, with many saying Apple's restrictions on what can be done with its software go far beyond those on Flash.

Source BBC NEWS

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