Video surveillance systems depend on IP networking equipment. In this guide, we explain the key pieces of equipment and features, explaining where and why they are typically used. The topics covered include:
- Fast / Gigabit / 10 Gigabit Ethernet
- Actual vs. Rated Throughput
- Ethernet Switches
- PoE vs non-PoE Switches
- Managed vs. Unmanaged Switches
- Routers / Default Gateways
- Media Converters - Fiber and Coax
- Ethernet over UTP Extenders
- Ethernet Network Distance
- Network Interface Cards
- Multiple NICs
- Customer Premise Equipment
- Racks and Shelves
The vast majority of network gear is rated for either 100 Mb/s (Fast Ethernet) or 1,000 Mb/s (Gigabit Ethernet/GbE). These ratings describe throughput capacity, i.e., how much data each port may handle. Other variants, such as 10 or 40 Gigabit Ethernet, are available though generally not used in surveillance.
There are three common speed classes in use in networks today:
- Fast Ethernet: 100 Mb/second
- Gigabit Ethernet: 1,000 Mb/s
- Higher speeds: 10 Gb, 40 Gb, 100 Gb/s
Fast Ethernet (100 Mb/sec) is used for connections to field devices, such as cameras, encoders, and I/O modules. Rarely do these devices support gigabit speeds. Despite multi-megapixel and 4K cameras becoming common (with some including gigabit ports), camera streams are typically 15 Mb/s and below, simply not large enough to warrant the use of Gigabit Ethernet for the bulk of the network.
By contrast, Gigabit Ethernet (GbE) devices are rated to handle 10X more data per second than Fast Ethernet devices. GbE devices are generally moderately more expensive (20-30%) than their equivalent Fast Ethernet counterparts. In surveillance, GbE is typically used to connect switches together, as Fast Ethernet is typically not fast enough for these backbones. Additionally, it may be used to connect servers to storage devices (NAS/SAN).