10 Gbps Link and Camera Drops for a New Production Hall
An industrial company is adding a production hall 450 m from its main building. The hall needs a 10 Gbps link between the core switch and a new access switch, six PoE security cameras, and Wi-Fi coverage in an area with corrugated metal walls. A 300 m reel of OM2 multimode fiber is already in a conduit, but the conduit has tight bends and one flooded section. The vendor proposes 10GBASE-SR SFP+ modules over the existing OM2, Cat6A from the access switch to each camera, and a two-node wireless mesh to cover the hall because pulling cable is expensive. Camera specifications: 802.3at Type 2, 12.5 W typical, 25.5 W peak; each camera is 60-90 m from the access switch. The core switch has spare SFP+ ports and 802.3bt-capable copper ports. Budget is tight, and facilities can schedule one cable pull.
1. Evaluate the 10GBASE-SR over OM2 proposal at 450 m. What media and optics are required, and what installation constraints matter?
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10GBASE-SR over OM2 cannot span 450 m. The standard reach for 10GBASE-SR is about 82 m on OM2 (33 m on OM1, 300 m on OM3, 400 m on OM4). The existing 300 m OM2 reel is also shorter than the 450 m path and sits in a flooded, tight-bend conduit. 10GBASE-LRM improves OM2 reach only to roughly 220 m, so it also fails. The correct choice is single-mode OS2 fiber with 10GBASE-LR (10 km) or 10GBASE-ER (40 km) optics; LR is sufficient and cheaper.
Because the conduit has a flooded section and tight bends, specify outdoor or armored single-mode cable, or install a new innerduct with proper bend radius; do not pull standard indoor fiber through a flooded conduit. The single cable pull should include spare strands. This also future-proofs the hall for 25G or 40G. The vendor SFP+ proposal is therefore not a distance-only issue; it is a media-standard mismatch.
2. For the six cameras, is Cat6A acceptable, and what PoE and distance checks would you require?
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Cat6A is appropriate for the camera drops if the channel stays within 100 m. The 60-90 m distances are close to the limit; the 100 m channel includes patch cords, service loops, and termination, while the permanent link should be limited to 90 m. Measure each path, not just the straight-line distance. Power is the bigger risk: each camera is 802.3at Type 2 with a 25.5 W peak, which is exactly the Type 2 PD limit. After cable loss over 90 m, the camera may see less than it needs at peak. The access switch is 802.3bt-capable, so use Type 3 or Type 4 power and confirm the switch total PoE budget for six cameras; if the budget is tight, use local power at the camera.
Cat6A supports 10GBASE-T and PoE, but for any run over 90 m permanent link, use fiber with local power or a media converter. Do not assume a 90 m run is safe without certifying length and measuring PoE voltage under load.
3. Should the two-node wireless mesh be used for hall coverage? What would you recommend instead?
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A two-node wireless mesh through corrugated metal is a poor bet. Metal walls strongly attenuate 5 GHz and can detune antennas; mesh also reduces throughput per hop and adds latency. Since the project already allows one cable pull, pull fiber to the hall and use wired access points with external antennas. If a cable pull were impossible, use a point-to-point bridge with directional antennas aligned through a window or opening, not a generic mesh node behind metal. Inside the hall, mount APs below the roof line and avoid placing them against metal; use directional or industrial APs rated for the environment. Verify coverage with a site survey after installation, and keep the camera and Wi-Fi networks on separate VLANs. The mesh proposal saves cable but risks failing the coverage requirement and adding an unreliable RF hop.