Rosenberger Optical Solutions & Infrastructure (Rosenberger OSI), a manufacturer of fiber-optic network cabling infrastructure, has now disclosed the outstanding innovation of its new PreCONNECT SEDECIM cabling system, after the system's market launch in mid-March.
"The special feature of PreCONNECT SEDECIM is that the ferrule endfaces of the MTP/MPO 16 fiber multimode connector are 8° APC angularly polished. Due to this angled polish, the return loss could be significantly improved," stated Harald Jungbäck, product manager for data center cabling systems at Rosenberger OSI.
In developing the PreCONNECT SEDECIM, which is optimized for the 400GBASE-SR8 transmission technology, the cabling specialist uses a technology that has already proven itself in singlemode applications. The APC 8° angled polish has always been used for singlemode MTP/MPO ferrule endfaces to achieve reliable return loss. In contrast to this, only the PC 0° straight polish was previously used for multimode MTP/MPO ferrule endfaces.
As pointed out by Rosenberger OSI, due to their PC 0° straight polish design, multimode MTP/MPO connectors were previously particularly susceptible to performance problems caused by dirt particles, which in the past often led to unreliable return loss values. In recent years, this problem has become increasingly severe due to the sharp rise in application data rates, notes the company. The introduction of reflection-sensitive PAM4 coding at 400GBASE-SR8 and other multimode applications with serial lane speeds of 50 Gbit/s has shown its full extent.
"When 400GBASE-SR8 was introduced to one of the world's largest hyperscalers in 2019, these problems were so severe that research results on the APC 8° angled polish on multimode MTP/MPO ferrule endfaces from Rosenberger OSI were used, which were already collected in 2012," added Rosenberger OSI's Jungbäck.
He continued, "The measurements prove that multimode MTP/MPO connectors with APC 8° angled polish, in contrast to those with PC 0° straight polish, guarantee a reliably high return loss in the application. Due to the clear facts of these tests, the hyperscaler, also in close cooperation with the MTP inventor and manufacturer US Conec, decided to specify the multimode MTP/MPO 16 ferrule endfaces APC 8°. This decision not only affected the cabling infrastructure but also the 400GBASE-SR8 Tranceiver Media Dependent Interface (MDI). There was also no discussion on this subject regarding our PreCONNECT SEDECIM. The research results clearly speak for themselves."
Thus 400GBASE-SR8 transceivers can now have both an MTP/MPO 16 PC 0° and an MTP/MPO 16 APC 8° as Media Dependent Interface. The distinguishing feature of the innovative MTP/MPO multimode connector system from Rosenberger OSI, with 16 fibers in a row and APC 8° angled polish, is a white bend protection boot on the black connector.