A quick look at the capabilities of SFTP CAT7 Cable might make you wonder what all the fuss is about because at least on paper, it has everything you could possibly want in an Ethernet cable. Originally ratified as a standard in 2002, Cat7 was the first Ethernet cable type to offer speeds of up to 10 Gbps over copper cables up to 100 meters long. Under ideal conditions, it can operate at frequencies up to 600 MHz. This is significantly higher than the Cat6 cable, although it is very close to the capabilities of Cat6A, which was developed a few years later.
Cat7 cables do have stricter standards for crosstalk than Cat6, roughly equivalent to Cat6A. It usually does this by incorporating tighter internal wire stranding, although shielding of individual wires and entire cables is also a common option.
What is Cat7? similar but not the same
While Cat7 cables sound great on paper—especially considering how long ago they were originally released—there are a few reasons why the standard isn't as useful or feasible as equivalents like Cat6A.
One of the most important reasons is that the Cat7 specification is a proprietary standard developed by a group of companies. It is not an IEEE standard, nor is it approved by the TIA/EIA. Cat7 cables do not use traditional RJ-45 Ethernet headers (technically known as 8P8C connectors). The GG45 connector used is a proprietary connector. Although it is backward compatible with RJ45, these connectors are difficult to come by. Cat7 cables are also compatible with TERA connectors, although this is also rarely used in the industry. (see below)
Inconsistencies with previous cable standards resulted in Cat7 becoming an extremely unpopular cable category and eventually spurred the development of Cat6A cable in 2008. While the standard proved to be more popular, it also added confusion. Marketing comparable Cat6A cables is difficult when Cat7 sounds better and newer with its higher number category. This has led some sellers to use Cat7 as a way of selling their Cat6A cables. So be sure to check the specs of any Cat7 cable you're interested in buying before entering your card details.
Cat7 is not supported
While connector preferences drive some people and companies away from Cat7, arguably the most important factor in its low popularity is its lack of official seals of approval from the Institute of Electrical and Electronics Engineers (IEEE) and the Electronic Industries Alliance (EIA). This doesn't preclude anyone from using Cat7 cables, but it does mean that many are less inclined to do so.
The lack of approval and the use of alternative connectors meant that networking hardware developers focused their support on 10Gb Ethernet over the RJ-45 connector, leaving GG45 and TERA connectivity options untapped. This only exacerbates the problems Cat7 faces in increasing its adoption.
What about Cat7A?
Like Cat6 and Cat6A, Cat7A is a further development of the Cat7 standard. Cat7A is designed to support the future 40G Ethernet connection standard at frequencies up to 1,000MHz, and it is powerful. Under the right circumstances, it can support 40Gb connections up to 50 meters and 100Gb connections up to 15 meters.
Unfortunately, this deviates further from the plans of the IEEE, which approved in 2016 (six years after Cat7A was ratified) that Ethernet cables officially supporting 40 Gbps speeds need to support up to 2,000MHz, meaning Cat8 cables are the only ones officially supported Cables support such speeds.
This resulted in little to no development work for a Cat7A-compliant product, rendering it almost useless despite its impressive capabilities.