Base T Technologies
In the 1980s, the IEEE 802.3 working group introduced twisted pair network cabling also known as BaseT. The first implementation was 10BaseT for 10 Megabit per second data rates. Since then, the IEEE 802.3 working group has ratified specification changes to support other speed and the latest amendments for BaseT technology were approved in 2016.
The data rates seem attractive but have sadly fallen behind where the industry has headed and adoption is non-existent. Two of the main deterrents to using 10GBaseT are:
- much higher power consumption
- higher implementation costs
The bleak future of BaseT technology has never been more apparent when we look at the potential successors in 25GBaseT and 40GBaseT. The top market players have analyzed 25GBaseT and 40GBaseT. After consulting with customers, analysts, and ecosystem providers, it became clear that there is little or no interest in this technology for the following reasons:
- The need for new Cat8 cable which has no deployment and is an expensive shielded cable
- The cable length restriction of 30 meters versus 100 meters in other BASE-T technologies
- The substantially higher power requirement when compared to SFP28 Direct Attach cable or Optical Modules operating at 25G
It is worth mentioning PoE for BaseT technologies since it has been a benefit for some applications mostly for lower data rate and lower power applications. PoE is power over ethernet, which is simply sending power over the same cable used for data for the sake of powering devices on the network. The technology does come with a penalty where a POE device will consume an extra 1 watt to implement. For end devices that use 10GBaseT and already consume 3 to 4 Watts for only the physical layer chip, one must now account for the added 1 watt for POE and then also account for the strain put on the server room to source POE while also having to process the much higher data rates of 10GBaseT. Most manufacturers realize this and thus very few implement 10GBaseT devices and even fewer implement such devices with POE support.
It is clear that SFP technologies are far more attractive than BaseT technologies and are the path forward for Ethernet speeds 10G and higher. Regardless, devices are most often powered locally since AC power is virtually always available throughout an installation. One alternative is to take a standard SFP cable installation and run a 2 conductor 12 or 16AWG copper cable alongside which provides power and ground. Hybrid cables are also becoming more available now from companies such as Belden and CommScope who are effectively following the market trends. If we implement such an installation that this would provide support for decades to come. This would support Emergent HR, BOLT, Xtreme, and Zenith cameras with respective speeds of 10GigE, 25GigE, 50GigE and 100GigE and cover at least the maximum supported length of 100m for POE BaseT technologies.
Summarizing SFP benefits over BaseT technologies:
- Virtually unlimited speeds
- Virtually unlimited cable lengths
- No large additional power consumption due to BaseT and POE technologies for reduced size and no fans.
- Lower cost due to excellent adoption by major industry players
- And reusable cable infrastructure options for later higher speed system upgrades