D
United Kingdom
If I remember correctly, 100BaseT uses two of the four pairs in UTP cable, whereas Gigabit uses all 4 pairs (4 x 250Mb/s). So if they're running power down one of the pairs then that pair is no longer available for Gigabit. And since there isn't a standard for 750BaseT using three pairs, you're back to 100BaseT.
Probably
D
dm15644
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AW: HDBaseT
Hm... comparing with Power over Ethernet I think it's fair to assume that all pairs are used for both power and data. But still:
(i) How do they think they get 100W though? For comparison, Power over Ethernet is limited to <13 Watts, and if they want to increase this to 100W but still use the same cables, the only option I see is to increase the voltage, say roughly, by a factor of 9... this would be >400 Volts then. I don't know the specs of RJ45 but I dare to say that this will be impossible. On top RJ45 is not touch safe, and in many european countries this means the voltage has to be <60 or even <48 Volts.
(ii) CAT5 supports 1 Gbps. How do they increase the bandwidth by a factor of 20? I'm not so much into compression algorithms, but maybe they reserve 1/10 for Ethernet and 9/10 for AV. That would leave an effective max of say 650 Mbps (very optimistic) to AV - is this enough to claim they have an uncompressed thoughput of >20 Gbps? It a factor of 30 something.
I really think the idea of using low cost standard wiring for AV is great, but I get a bit the impression that the marketing department of that initiative is too optimistic, which will once again make customers feel disapointed and may hinder the success of a great idea.
/jayrock
Hm... comparing with Power over Ethernet I think it's fair to assume that all pairs are used for both power and data. But still:
(i) How do they think they get 100W though? For comparison, Power over Ethernet is limited to <13 Watts, and if they want to increase this to 100W but still use the same cables, the only option I see is to increase the voltage, say roughly, by a factor of 9... this would be >400 Volts then. I don't know the specs of RJ45 but I dare to say that this will be impossible. On top RJ45 is not touch safe, and in many european countries this means the voltage has to be <60 or even <48 Volts.
(ii) CAT5 supports 1 Gbps. How do they increase the bandwidth by a factor of 20? I'm not so much into compression algorithms, but maybe they reserve 1/10 for Ethernet and 9/10 for AV. That would leave an effective max of say 650 Mbps (very optimistic) to AV - is this enough to claim they have an uncompressed thoughput of >20 Gbps? It a factor of 30 something.
I really think the idea of using low cost standard wiring for AV is great, but I get a bit the impression that the marketing department of that initiative is too optimistic, which will once again make customers feel disapointed and may hinder the success of a great idea.
/jayrock