So they're vertical divisions and this has an impact on how you design the networks on them. You have what are called "RDPs" - remote distribution points - massive network switches in each one of those fire zones. And to get all of these different signals into the cabins you have what are called "cabin switches" - so every pair of cabins will have a cabin switch that does the TV, the VoIP, the water, the lighting - all of those different things.
Cruise ships are divided into vertical "fire zones"
So they go vertically down the ship, so you don't have to make holes going across to carry those cables.
Vertically down these zones are a series of cabin switches, and the cabin switch does the job of handling the VLAN trunking for access to services.