The QSFP-DD (Quad Small Form Factor Double Density) and OSFP (Octal Small Form Factor Pluggable) cable systems mean that not one, but two Leoni product families have made the leap to 400G transmission over copper. Both solutions are based on the company's thin and efficient ParaLink 25s bulk cable. This high-performance cable also provides the required high signal integrity along with a low packing density as a 16-pair version. For QSFP-DD, Leoni uses its ParaLink 25s with a maximum gauge of 28 AWG and a maximum length of 3 meters; for OSFP, simulations even showed that a maximum of 4 meters is possible with a gauge of 26 AWG.
As a member of the Multi Source Agreement (MSA) Groups for QSFP-DD and OSFP, Leoni is aligned with standardization efforts to electromagnetically simulate the development of cable systems using its own components and to test the feasibility of active and passive copper solutions for these standards. Initial prototypes have confirmed the findings of these simulations. For example, OSFP and QSFP-DD cable systems passively transfer 8 x 25 Gbit/s at 25 GHz without interference (corresponding to 200 G with NRZ transmission) or up to 8 x 50 Gbit/s actively (corresponding to 400 G with PAM4 modulation). In the simulation, active OSFP or QSFP-DD cable systems can also overcome longer lengths with full signal integrity when transferring 400 G of data thanks to an integrated PAM4 amplifier.
Along with several active and passive end-to-end solutions, as well as notable versions such as QSFP-DD based on 8 x SFP56, OSFP on 8 x SFP56, QSFP-DD on 2 x QSFP56, and OSFP on 2 x QSFP56, Leoni will soon offer a starter cable that transmits between QSFP-DD and OSFP. This solution will establish full compatibility between the two standards and backward-compatible systems.
