Sub-comms Cabinet - Components

There are a few ways this might  be done. There will be at least a pair of fibres  in optic cable, uplink and downlink, but quite likely more pairs will be run in parallel to create a 'wider'  bandwidth pipe and also to avoid single point failure. Compared to the cost of downtime, the effort of running a spare fibre and leaving it 'dark' as a fall-back is common,


The pairs of fibre  will probably terminate in a hub that has a socket for one or more  fibre optic transceivers.Nowadays these are replaceable modules, each contains a small laser for the transmitting side and a photo-diode for the receiver the smallest of these  transceivers are  commonly in 10gigabit units. For those with a bit more data to shift 16 and 32gig units exist, and  for those with very deep pockets, up to 400gig, though these are really 4 lasers and 4 receivers of different wavelengths (like colours of light)  and interface in effect much like 4 fibres in parallel, and can indeed be set up as independent or combined networks.


Then there are several variations depending on the laser wavelengths and the type of fibre that is used (single mode fibres have less dispersion over long distances but they are pricier and so are the transceivers, multi-mode fibres are more tolerant of alignment errors and so on, and the transceivers are a bit cheaper, but the range is hundreds of metres rather than km.)


The hub will take in the fibre optic interface or interfaces and redistribute data to a number of wired Ethernet ports, which will go either directly or via further hubs to split the signals further  to the outbound lines or groups of lines.

The hubs are quite likely to be programmable so they are more like 'data switches' and  can use routing rules that improve security and efficient use of the system - for example a common requirement is to  avoid data that is intended to pass between machines on the same floor to be sent and down to other floors when it does not need to be.


Mike,

There are a few ways this might  be done. There will be at least a pair of fibres  in optic cable, uplink and downlink, but quite likely more pairs will be run in parallel to create a 'wider'  bandwidth pipe and also to avoid single point failure. Compared to the cost of downtime, the effort of running a spare fibre and leaving it 'dark' as a fall-back is common,


The pairs of fibre  will probably terminate in a hub that has a socket for one or more  fibre optic transceivers.Nowadays these are replaceable modules, each contains a small laser for the transmitting side and a photo-diode for the receiver the smallest of these  transceivers are  commonly in 10gigabit units. For those with a bit more data to shift 16 and 32gig units exist, and  for those with very deep pockets, up to 400gig, though these are really 4 lasers and 4 receivers of different wavelengths (like colours of light)  and interface in effect much like 4 fibres in parallel, and can indeed be set up as independent or combined networks.


Then there are several variations depending on the laser wavelengths and the type of fibre that is used (single mode fibres have less dispersion over long distances but they are pricier and so are the transceivers, multi-mode fibres are more tolerant of alignment errors and so on, and the transceivers are a bit cheaper, but the range is hundreds of metres rather than km.)


The hub will take in the fibre optic interface or interfaces and redistribute data to a number of wired Ethernet ports, which will go either directly or via further hubs to split the signals further  to the outbound lines or groups of lines.

The hubs are quite likely to be programmable so they are more like 'data switches' and  can use routing rules that improve security and efficient use of the system - for example a common requirement is to  avoid data that is intended to pass between machines on the same floor to be sent and down to other floors when it does not need to be.


Mike,