What's the difference between managed and unmanaged switches for surveillance?
Managed switches offer VLANs, QoS, port mirroring, and SNMP monitoring—critical for multi-camera, multi-vendor, or compliance-heavy installs. Unmanaged switches simply forward frames with no intelligence; they're plug-and-play but broadcast all traffic, creating security and bandwidth waste. Any deployment over 8 cameras should use managed.
How do I calculate PoE budget for my cameras?
Add the maximum power draw (watts) of every connected device, then add 20–30% safety margin. For example: 12 cameras × 10W + 2 access readers × 3W = 126W total; choose a PoE++ (95W) + PoE+ (30W) combo, or two PoE++ switches. See PoE budget planning guide for detailed examples.
Can I use an unmanaged switch to connect managed switches together?
Yes, as a passive bridge, but it won't carry VLAN or priority tags reliably over longer distances. For multi-switch sites, use managed-to-managed connections via 802.1Q trunk ports and fiber uplinks to isolate broadcast traffic and prevent core collapse.
What's the benefit of industrial-rated switches for outdoor cameras?
Industrial switches are rated for wide temperature ranges (−40–70°C), conformal coating for moisture/corrosion, fanless designs, and redundant power inputs. Standard commercial switches fail within months in direct sun, unheated vaults, or salt-spray environments. Always use industrial for outdoor or vehicle-mounted gear.
Do I need 10GbE uplinks for my switch?
1GbE (1,000 Mbps) uplinks support ~80–100 Mbps of camera bitrate (conservative rule: 1/10th link speed). For 20+ 4K cameras or high-motion HD streams, upgrade to 2.5GbE or 10GbE to prevent NVR throughput bottlenecks. Fiber optics are preferred over copper for long runs (>100m).
What's Spanning Tree Protocol (STP) and when do I need it?
STP prevents broadcast loops in redundant (ring or mesh) topologies by disabling backup links until primary fails. Rapid STP (RSTP) converges in <1 second—essential for critical facilities. Simple linear or star topologies don't need STP, but any dual-uplink or ring design must enable it to avoid network failure during incidents.
