Thursday, July 13, 2017

SFP-DD MSA to define 2x 25/56 Gbit/s interface Spec

The SFP-DD Multi-Source Agreement (MSA) Group has announced plans to develop the specification for a high-speed, double-density small form-factor pluggable (SFP-DD) interface.

Under the MSA, participating companies will address the technical challenges of delivering a double-density SFP interface and ensuring mechanical interoperability for module components produced by different manufacturers. New SFP-DD-based networking equipment will be designed to support legacy SFP modules and cables, as well as the new double density products.

Specifically, the MSA group will develop operating parameters, signal transmission speed goals and protocols for the SFP-DD interface, which expands on the existing SFP pluggable form factor electrical interface as widely adopted in data centres and other networking platforms. It was noted that multi-vendor SFP modules and assemblies are available for a range of data rate speeds and reaches for data transmission applications such as hubs, switches, routers and servers.

The current SFP interface single electrical lane operates up to 25 Gbit/s NRZ or 56 Gbit/s PAM4; the new SFP-DD electrical interfaces will be designed to support 2 lanes operating at up to 25 Gbit/s NRZ or 56 Gbit/s PAM4 per lane, thereby enabling solutions with up to 50 or 112 Gbit/s PAM4 aggregate bandwidth.

By doubling the lane density and data speed of SFP transceivers, the SFP-DD specification will help address increased port density and scalability requirements in next-generation applications, with a focus on the server side interconnect. An SFP-DD server port, combined with QSFP-DD switch ports, can enable an overall doubling of the port density in network applications.


  • Founding members of the SFP-DD MSA group include Alibaba, Broadcom, Brocade, Cisco, Dell EMC, Finisar, Hewlett Packard Enterprise (HPE), Huawei, Intel, Juniper Networks, Lumentum, Mellanox Technologies, Molex and TE Connectivity.