/. Terabit Ethernet is Dead, for Now
joelja at bogus.com
Sun Sep 30 21:58:21 UTC 2012
On 9/30/12 12:05 PM, Jimmy Hess wrote:
> On 9/29/12, Masataka Ohta <mohta at necom830.hpcl.titech.ac.jp> wrote:
>> Jared Mauch wrote:
>> The problem is that physical layer of 100GE (with 10*10G) and
>> 10*10GE are identical (if same plug and cable are used both for
>> 100GE and 10*10GE).
> Interesting. Well, I would say if there are no technical
> improvements that will significantly improve performance over the best
> possible carrier Ethernet bonding implementation and no cost savings
> at the physical layer over picking the higher data rate physical
> layer standard, _after_ considering the increased hardware costs
> due to newly manufactured components for a standard that is just
There is a real-estate problem. 10 sfp+ connectors takes a lot more
space than one qsfp+. mtp/mpo connectors and the associated trunk ribbon
cables are a lot more compact than the equivalent 10Gbe footprint
terminated as LC. When you add cwdm as 40Gb/s lr4 does the fiber count
drops by a lot.
> E.g. If no fewer transceivers and fewer strands of fiber required,
> or shorter wavelength required, so it doesn't enable you to achieve
> greater throughput over the same amount of light spectrum on your
> cabling, and therefore lower cost at sufficient density, then: in
> that case, there will probably be fairly little point in having the
> higher rate standard exist in the first place, as long as the
> bonding mechanisms available are good for the previous standard.
> Just keep bonding together more and more data links at basic units of
> 10GE, until the required throughput capacity has been achieved.
> It's not as if a newer 1 Tbit standard, will make the bits you send
> get read at the other end faster than the speed of light. Newer
> standard does not necessarily mean more reliable, technically better,
> or more efficient, so it is prudent to consider what is actually
> achieved that would benefit networks considered to be potential
> candidates for implementation of the new standard, before actually
> making it a standard...
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