Submarine Cable Systems
Submarine Cable Systems — 3 vendors and operators, each broken down by layer L1 to L7: what they sell at that layer, and which layer is their home turf.
SubCom
Home turf: L1 / L2
L1 Physical
This is this domain's star layer and the centre of gravity for the whole category. A submarine cable system at this layer divides into two parts: the wet plant is what sits in the sea — the cable itself, repeaters and branching units; the dry plant is the equipment in landing stations (see L2). The wet plant has three key components.
L2 Data Link
This is this domain's second star layer, covering the dry plant — the Submarine Line Terminal Equipment (SLTE) in landing stations, the equipment turning customer data into optical signals transmissible over the cable and back again.
L3 Network
This layer is explicitly empty — no product or service. A submarine cable system is transmission infrastructure: its responsibility ends at delivering optical signals reliably to the other side of an ocean, and it makes no routing decisions and does not understand the IP packets crossing it.
L4 Transport
This layer is explicitly empty — no product or service. A submarine cable system does not terminate, proxy or optimise transport-layer connections, and TCP and UDP traffic crossing it is entirely transparent payload.
L5 Session
This layer is explicitly empty — no product or service. This domain delivers physical transmission systems and engineering services, and no session-layer product exists.
L6 Presentation
This layer is explicitly empty — no product or service. This domain has no encryption capability as a standalone product line. One reality deserves stating honestly here: submarine cables have long been regarded as a subject of interest for communications interception, and a submarine cable system does not itself encrypt the data it carries — so confidential…
L7 Application
This layer is the submarine system's operational interface, limited in content but real. At its core is system network management: monitoring optical power and error rates across sections, collecting repeater status, and on failure estimating the fault location (using optical time-domain reflectometry and similar methods to determine roughly which stretch ha…
NEC Submarine Network
Home turf: L1 / L2
L1 Physical
The wet plant's composition (depth-segmented cable armouring, repeaters running unrepaired for something on the order of twenty-five years, high-voltage DC remote power feeding) and the fact that cable faults overwhelmingly occur in shallow water are explained fully at L1 of this site's SubCom domain; the mechanics are generic and are not repeated here.
L2 Data Link
This is this domain's second star layer and where its real strength lies. The role of terminal equipment (SLTE), coherent optical modulation and forward error correction, and the full mechanics of the open cable industry shift are explained at L2 of this site's SubCom domain and are not repeated here.
L3 Network
This layer is explicitly empty — no product or service. The reason matches L3 of this site's SubCom domain: a submarine system is transmission infrastructure whose job ends at delivering optical signals reliably to the other side of an ocean, making no routing decisions and not understanding the IP packets crossing it.
L4 Transport
This layer is explicitly empty — no product or service. A submarine system does not terminate, proxy or optimise transport-layer connections, and traffic crossing it is transparent payload (reasoning at L4 of this site's SubCom domain).
L5 Session
This layer is explicitly empty — no product or service. This domain delivers physical transmission systems and equipment, and no session-layer product exists.
L6 Presentation
This layer is explicitly empty — no product or service. This domain has no encryption capability as a standalone product line. A submarine system does not itself encrypt the data it carries, and confidentiality rests with whoever uses the capacity (full treatment at L6 of this site's SubCom domain).
L7 Application
Network management's functions (monitoring optical power and error rates, collecting repeater status, estimating break locations on failure) and why maintenance agreements predict recovery speed better than technical specifications are explained fully at L7 of this site's SubCom domain and are not repeated here.
ASN (Alcatel Submarine Networks)
Home turf: L1 / L7
L1 Physical
The wet plant's composition and engineering constraints (depth-segmented armouring, repeaters running unrepaired for something on the order of twenty-five years, high-voltage DC remote power feeding, faults overwhelmingly occurring in shallow water) are explained fully at L1 of this site's SubCom domain; the mechanics are generic and are not repeated here.
L2 Data Link
The role of terminal equipment (SLTE), coherent optical modulation and forward error correction, and the full mechanics of the open cable industry shift are explained at L2 of this site's SubCom domain and are not repeated here.
L3 Network
This layer is explicitly empty — no product or service. The reason matches L3 of this site's SubCom domain: a submarine system is transmission infrastructure whose job ends at delivering optical signals reliably to the other side of an ocean, making no routing decisions and not understanding the IP packets crossing it.
L4 Transport
This layer is explicitly empty — no product or service. A submarine system does not terminate, proxy or optimise transport-layer connections, and traffic crossing it is transparent payload (reasoning at L4 of this site's SubCom domain).
L5 Session
This layer is explicitly empty — no product or service. This domain delivers physical transmission systems and engineering services, and no session-layer product exists.
L6 Presentation
This layer is explicitly empty — no product or service. This domain has no encryption capability as a standalone product line. A submarine system does not itself encrypt the data it carries, and confidentiality rests with whoever uses the capacity (full treatment at L6 of this site's SubCom domain).
L7 Application
This is this domain's second star layer, because it carries a fact found nowhere else on this site. Network management and maintenance agreement mechanics are at L7 of this site's SubCom domain and are not repeated.