Although the newly built data center has been directly connected to 25G and 100G, there are still many 40G QSFP+ modules and ports in the existing network. Once used, 40G can continue to undertake aggregation and disconnection access. This article explains three things clearly: 40G module type classification, wire removal and connection methods, and route judgment for upgrading to 100G.

Let's first understand the common types of 40G

40G is divided into two categories: parallel and wavelength division: SR4 uses MPO multi-mode parallelism, typically at the 100-meter level; LR4 uses two-core single-mode four-wavelength division to reach 10 kilometers; ER4 is used for longer distances. On the network card side, the Intel XL710 series is mature, such as dual-portPCI-EX8 40G dual optical port fiber optic network card (Intel XL710 chip). Just choose the right port according to the distance. There is no need to fit the new 100G solution back to the old 40G port.

Removal of sutures: one mouth becomes four

The 40G QSFP+ port can be split into 4 10G channels through breakout cables: for short distance use in the cabinet40G to 10G DAC high speed cable, used across cabinets or when bending of cables is required40G to 10G AOC active optical cable. Pay attention to three points: the switch side must first manually turn on the disconnection mode; the lengths of the four branches should be as consistent as possible to avoid the remaining wires from being coiled to block heat dissipation; do not mix different brands of branch network cards.

Upgrade route to 100G

  • After the switch is replaced with a QSFP28 port model, most of the QSFP28 ports in the direct connection segment are compatible with 40G modules. During the transition period, they will be mixed and then replaced segment by segment, subject to the compatibility list;
  • It is not recommended to purchase a 40G network card for server access. The unit bandwidth cost of switching to 25G dual-port is more reasonable;
  • The loss of the LR4 long-distance optical fiber link is retested before replacing it with 100G. In most scenarios, the optical fiber can continue to be used;
  • The existing 40G modules can be converted into a spare parts pool, eliminating the need to clear the inventory at once.

40G is positioned as a stock rather than a main force: old ports and disconnected access allow it to continue to work. New projects are directly planned according to 25G access and 100G aggregation. For stock transformation plans, please call 0755-83179002 to check the equipment compatibility list with EB-LINK technical support.