Altronix eBridge Examined
While Ethernet over Coax (EoC) adapters have allowed existing analog camera cables to be reused for some time, they have seen limited adoption. The biggest hindrance to their widespread use is price, with most units costing as much as, or more than, pulling new UTP cables. However, Altronix, best known for their line of power supplies, has released the eBridge EoC adapter at a price point much lower than existing entries. In this update, we will look at the eBridge product, its capabilities, and compare it to other EoC providers, such as Veracity and NVT.
The Altronix eBridge is a coax Ethernet adapter, capable of 100Mbps Fast Ethernet speeds. The eBridge supports distances of up to 1,500' over RG-59, though data rates are reduced at greater distances, falling to 25Mbps at 1,500' according to specifications.
The eBridge, unlike many recent releases from competitors, does not support PoE up the coax, requiring 12VDC/24VAC power at the camera end. In many cases this is not an issue, as existing power supplies from the analog camera system may be used. An increasing amount of manufacturers are opting to make their camera PoE-powered only. Altronix does offer the NetWay1, a 24VAC-powered PoE injector, which may be used in these cases, but this adds installation complexity and material cost.
The eBridge is available now, and sells online for around $200.
Composite Video Transmission
One feature of the eBridge which we have not seen in other offerings is its composite video signal support. This feature allows IP cameras equipped with analog outputs to transmit video over the coax, in addition to data. At the head end, this anlaog video is output from the eBridge receiver, for connection to monitors or matrix switchers for viewing. This may be useful for small installs who would like to watch a camera or two without using a PC client. It may also be useful for large systems with existing matrix switchers who wish to use the existing matrix/monitors for live viewing, while recording a full-resolution megapixel stream. This is similar in function to Sony's Hybrid Camera series.
The eBridge is so far the lowest-cost EoC converter we have seen from a reputable manufacturer. Offerings from Veracity, NVT, Comnet, and others are typically in the range of $400-450 per pair, about twice the price of the eBridge.
While each of these products has slightly differeing featureset, the main feature seen in them, not included in the eBridge, is PoE up the coax. eBridge users requiring PoE will need to use the Altronix NetWay1, which adds approximately $40 to each camera. This is potentially an issue when using low-cost IP cameras (such as ACTi's latest additions, or the Sony X Series) which are only capable of PoE power, not 12VDC/24VAC. Even with this added cost of the injector, the eBridge is still well below the price of competitors.
Other options may support higher data rates at increased distances. Veracity's HighWire PowerStar, for instance, is specified to support full bandwidth at distances up to 1,600'. However, we estimate that most cameras are in the range of 500' or less, with average being below 200'. At these distances, throughput should not be an issue.
For analog camera users looking to migrate to IP, the cost of recabling is often one of the hurdles to making this decision. The eBridge's pricing is very close to the average price of a new UTP cable, generally in the range of $150-200. At these prices, only a small increase per camera over new cables, EoC becomes a much more attractive choice, especially when considering the reductions in installation labor and disruption to the facility.
Additionally, Altronix has far better brand recognition in the security industry than competitive EoC products. As one of the most widely-used power supply lines in the industry, we suspect their reputation would drive some integrators to propose using the eBridge, where they have shied away from other EoC lines, whose names are not as well-recognized.