Hi Nick, Thanks for your reply. I don't have anything more concrete to add to the general concerns I wrote about regarding the latest generation very high density electronics being installed in street cabinets for a decade or more.
There are low-noise, low distortion GHz amplifiers in metal boxes underground and strung on wires for the HFC (Hybrid Fibre Coaxial = cable TV/Internet) systems. Some of these contain electro-optical conversion - so they also have lasers, photodiodes etc. and more amplifiers. They also have microcontroller-based management systems. These are powered from the coaxial cable itself, which has an AC voltage - 50 to 90 volts I recall - imposed on it from mains power supplies and perhaps battery-backed up inverters. These amplifiers (an amplifier in each direction, with filters, for two different frequency ranges) and electro-optical converters are totally sealed against water and dust and are passively cooled via their aluminium enclosures. However, an HFC amplifier is not at all as complex or power-hungry as a hundred or so VDSL transceivers and a cabinet, with all the fancy gigabit switching and management circuitry, power supplies, battery backup in the box etc. which is required for Fibre to the Curb (the Coalition's preferred plan instead of the NBN's Passive Optical Network fibre to the premises plan). I am concerned about dust, moisture, fungus, insects and spiders, flood, extreme high temperatures and daily temperature cycling. These cabinets would need to be well protected from vehicles running into them, since they would be expensive to replace and would take many days to install, wire up to the remaining cables etc. Without wanting to sound too paranoid, there could also be a theft problem with the backup batteries and perhaps even the gold and copper scrap value. Plain fibre has no scrap value at all. - Robin On 2013-04-23 11:17 AM, Nick Ross wrote: > Hi Robin, > > Did anyone follow up on this? It's a very interesting point. I've asked the > question of some FTTN cabinet specialists. > > I've heard enough about datacenters to know that some flavours of the newer > ones are designed to run very hot indeed - the electronics can cope with it. > > However, I asked about cooling i cabinets before and was told that they > have several fans in them. But that's surely not going to cut it in an > Australian summer? Or any perma-hot parts of Australia??? > > What other hot countries have FTTN (at least in their hot parts)? > > N _______________________________________________ Link mailing list [email protected] http://mailman.anu.edu.au/mailman/listinfo/link
