The network migration to 100G services has made remarkable technological progress towards meeting new applications and reducing upgrade costs. In our previous blog post 'Optimize your cabling infrastructure for 100G'we outlined the steps to evaluate existing fiber cabling to determine the appropriate transceiver. Missing at that time was a solution for upgrading 40G multi-mode fiber links that span up to 300 meters. A migration path to 100G using this existing fiber installation was not available, until now. The new QSFP28 ESR4 transceiver form factor is the missing link for this 100G upgrade puzzle.
The QSFP28 ESR4 transceiver enables networks to quickly upgrade to a 100G (4x25G) environment without replacing existing fiber or network layouts. The QSFP28 ESR4 accepts a standard MPO12-type connector and will connect 100G fiber links up to 300 meters over OM4.
Updated 100G Short Reach Applications Transceiver Quick Selection Guide
ProLabs offers a complete portfolio of 100G Compatible Optical Transceivers, including CFP, CFP2, CFP4 and QSFP28 transceiver options, including extending distances with 100G Long Reach in an efficient QSFP28 package and a green solution which consumes 30% less power.
Contact us to learn more about how ProLabs solutions can help you simplify and optimize your migration to 100G.
While there are multiple form-factors for 400G bitrates (see our blog article: "400G - Which form factor?"), the QSFP56-DD and OSFP are clearly in competition for all "access" and "data-centre" applications.
QSFP-DD and OSFP Specifications
QSFP56-DD - stands for QSFP56 Double Density - 4x (quad) 50G x2 (double density) = 400G The QSFP56-DD, also called 400G QSFP-DD, is standardised by the QSFP-DD MSA Group (http://www.qsfp-dd.com/). It has a similar size compared to the QSFP transceiver (QSFP+/QSFP28/QSFP56) but it has 8 data lanes instead of 4, reason for the "Double Density" name.
The QSFP-DD port (the cage) is backward compatible with the QSFP transceiver: we will be able to plug a QSFP28 into a QSFP-DD port (if the switch support it).
While there is no direct thermal management mechanism (no integrated heat-sink), the QSFP-DD allows a maximal power consumption of 12 watts (initial spec), challenging the transceiver industry to release a 400G technology not exceeding that. Recently, the QSFP-DD MSA Group has published an application note confirming the 15W feasibility, while the last specification (in its version 4.0) defines a Power Class 7 (up to 14W) and a Power Class 8 (>14Watts).
Juniper - PTX10003, QFX 5220 and QFX10003 supporting QSFP-DD
Nokia - 7750 SR supporting QSFP-DD
* the list is not exhaustive and is likely to change rapidly and frequently.
1U Rack - 32 or 36 ports?
Both QSFP-DD and OSFP remain "compact" for access and data-centre applications. However a 1U rack can handle maximum 32x OSFP ports, while the same rack can handle 36x QSFP-DD ports. More density with QSFP-DD but also more challenges in term of power dissipation.
800G ready?
The 800G bitrate (8x 100Gbps PAM4) will be available on the OSFP form factor as it has been designed for. A QSFP-DD, called QSFP112-DD, will potentially be released for 800G application. It will have the same dimensions as QSFP56-DD but the electrical interface will be optimised to support 112Gbps bitrate (100G PAM4) per lane.
Conclusion
While a trend is clearly visible, it is still too early and dangerous to define a winner. The QSFP-DD has a real advantage of being natively backward compatible with the QSFP form factor, while the OSFP seems to have more robustness (heat dissipation, space for components and 800G ready).
Except for Arista's customers, the network operators will decide the form factor when selecting the switch vendor… and it will be QSFP-DD. Actually, only Arista has released a switch with OSFP ports.
But, the situation can drastically change: the switch vendors are in the early stage of releasing the 400G switches; we have seen only few demos and some announcements but not more. The first half of 2019 will probably be key to observe other announcement, to confirm or infirm the actual trend.
You are an Arista customer and you doubt about going to OSFP or QSFP-DD?
Because the OSFP has more space and less power restriction, the transceiver industry will use this form factor for the first instances of complex technology (more than 2km, DCI application, etc.) but will rapidly support the same technology on a QSFP-DD. The early-adopters might prefer the OSFP for this reason.
If we follow the actual trend, it seems that the switch vendors are going for QSFP-DD, even Arista is coming with a dedicated version… backward compatibility, lowest power consumption and smallest form factors are key drivers for a long-term adoption.
Thanks to the 400G technology, a new QSFP28 100G module type is coming. ProLab's Product Solutions Specialist, Ambroise Thirion, explains more about this new technology
London, 19 November – The road to 200G and 400G is set to become clearer after LINX103 in London today, as Ambroise Thirion, Technology Solutions Specialist at ProLabs presents the company’s roadmap towards achieving 400G.
The past few years has seen ProLabs, industry leader in compatible optical transceivers, support its customers in data centres with bitrates of 25G, 50G and 100G. This trend of expansion to meet consumer demands is set to extend throughout 2019 and early 2020, with the recent development of form factor specific technologies to enable up to 400G.
This need for higher bitrate is being driven by the growing demand for bandwidth, the increased need for density and high-volume capabilities, all while minimising power consumption and power dissipation. With VOD and 5G, the number of connected devices worldwide set to increase markedly by 2020 and this demand is being felt industry wide.
“Upgrading and future-proofing networks can be daunting and costly, which is why it is so important organisations take the time to understand; why they are moving to 200G or 400G, how these bitrates can be achieved using the right technology and when the preferred solution can be expected to hit the market,” said Thirion.
“Some of the larger data centres are putting plans in place to upgrade to 200G as soon as its available, while another scenario we are seeing is that organisations are opting to wait for a more mature technology and looking for a direct and complete deployment with 400G. It is ultimately up to the organisation on which route to take and when to take it. This is where our roadmap to 400G, presented at LINX 103 today, can help,”
200G and 400G are achievable thanks to a number of technologies including; PAM4 modulation, GEARBOX for 400G and a set of new form factors such as QSFP-DD, OSFP and CFP8. As compared to the previous binary mechanism NRZ, PAM4 enabled transceivers offer customers double the transmission bitrate by increasing the levels of transmission of pulse-amplitude modulation.
For 400G specifically, the initial form factors will include eight lanes of 50G PAM4, while other versions will utilise the latest GEARBOX technology to facilitate four lanes of 100G PAM4. The GEARBOX component combines the power of numerous PAM4 modules to achieve the speed desired, in this case, 200G or 400G. Currently under development, ProLabs customers can expect solutions for up to 200G to be available from 2019 and 400G to be available from end of 2019.
Thirion added: “While there is no single best way to combine solutions for the ideal network, ProLabs have products available across a variety of form factors to suit specific applications. We have a proven track record in keeping our customers ahead of the curve, and the impending 200G/400G upgrade is no different. We are already supporting our customers in up to 100G networking and look forward to enabling 400G in the near future,”
The ProLabs team head to LINX103 and launch the 400G roadmap to the EMEA market. ProLabs Product Solutions Specialist presented to the elite membership of LINX and the content was very well received and publicised
