The Next Category Cable Is Here

Data transmission rates are burgeoning, and cabling is evolving almost as fast. Cat 6A’s successor, the much anticipated Category 8, is finally here – along with its ability to support 25 and 40GBASE-T networks.

While Cat 8 supports fast networks, it’s not without limitations. The governing TIA, IEEE, and ISO standards set the limit for the Cat 8 two-connector channel cables at 30 meters. At this point, Cat 8 is only applicable for data center access layers – not enterprise or premise networks.

When data centers are ready to move forward with a network that supports a faster (than 10 gig) speed, data center managers will appreciate the advantages of having Cat 8 cabling in place. In addition to significantly increased transmission speeds, they’ll also celebrate Cat 8’s:

  • Compatibility with most network topologies – top of rack (ToR), middle of row (MoR), and end of row (EoR)
  • Universal connector (RJ-45) – the global standard for servers and switches
  • Auto-negotiation capabilities

Data center managers who use a ToR topology can choose between twinaxial cable or Cat 8 for copper infrastructure. The ToR model uses a more simplified design – short intra-rack cable runs with a few uplinks to aggregate switches. If you choose Cat 8 over twinax, you’ll gain the benefit of auto-negotiation, which allows two Ethernet devices to connect and find a common speed that they both support. This feature allows for smooth, staggered upgrades and mixed speeds in the same cabinet.

Fans of MoR and EoR topologies will have their servers cabled back to a single switch. That switch will be dedicated to a row of server racks. This arrangement has just one switch to manage per row, a welcome simplification for data center managers; but it also calls for longer links than the ToR design, which means options for cable runs are either Cat 8 or multimode fiber, eliminating the short-length twinax option. Fiber offers several benefits, but it’s also more expensive.

There's a lot to consider. To learn more details about practical applications for Cat 8 cabling, read our: Practical Applications for Cat 8 tech brief.