Cisco S-Class Optics vs. Non-S-Class Optics

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Cisco announced the S-class optics in December last year. What’s the detailed information about the new S-Class Optics?

This new set of optics does not have unnecessary features for these applications, leading to a more attractive price.

S-class optics are available only in the most common reaches needed in enterprise and data center applications. The following Table shows 10G and 40G S-class PIDs.

S-Class Optics

Data Rate Protocol Media Reach Temp. Range S-Class PID
10G Ethernet MMF (duplex) 300m Commercial SFP-10G-SR-S
10G Ethernet SMF (duplex) 10km Commercial SFP-10G-LR-S
10G Ethernet SMF (duplex) 40km Commercial SFP-10G-ER-S
10G Ethernet SMF (duplex) 80km Commercial SFP-10G-ZR-S
40G Ethernet MMF (ribbon) 100m Commercial QSFP-40G-SR4-S
40G Ethernet SMF (duplex) 10km Commercial QSFP-40G-LR4-S

From the data sheet of Cisco S-Class Optics, we cannot tell the main differences between the S-class and Non-S-class optics. But from some users’ feedback and experiences, we can find out some difference between the S-class and the Non-S-class…

S-class is Ethernet only, no OTN (Optical Transport Network) or WAN-PHY (Wide Area Network Physics). In addition, it is no TAA compliance for S-class. Moreover, S-class and non-S-class optics are with different temperature ranges. Thus, if you are an enterprise or datacenter environment that doesn’t need any special long distance, temperature tolerances, or other special features, S-Class optics are cheaper and should be just fine for you. But there is no doubt that the differences are not the main concerns of Cisco when they introduced the S-class. The low price is the main selling point, and the compatibility is no problem.

There are some questions that are related to Cisco S-Class Optics asked by users, which may help you know the S-Class Optics and Non-S-Class Optics more.

Q1: Is S-Class SFP+ compatible with “normal” SFP+? We have some new “S-Class” SFP+ LR transceivers. Part Number: SFP-10G-LR-S=

But we need to connect these SFPs with “normal” X2 LR transceivers. Part Number: X2-10GB-LR=. Anyone have experience or knows if “S-Class” transceivers are fully compatible with “normal” transceivers?”

…From the data sheet we can know that the “10GBASE-LR 1310nm SMF” matches the standard of the X2-10GB-LR= transceivers, so they should work fine.

SFP-10G-LR-S=—Features and Benefits

Main features of Cisco 10GBASE SFP+ modules include:

  1. Smallest 10G form factor
  2. Commercial temperature (0 to 70°C) only
  3. Supports 10GBASE Ethernet only
  4. Hot-swappable input/output device that plugs in to an Ethernet SFP+ port of Cisco platforms
  5. Provides flexibility of interface choice
  6. Supports digital optical monitoring capability
  7. Cisco quality identification (ID) feature that enables a Cisco platform to identify – optics supported by Cisco technology
  8. Optical interoperability with 10GBASE XENPAK, 10GBASE X2, and 10GBASE XFP interfaces on the same link

SFP-10G-LR=—Features and Benefits

  • Industry’s smallest 10G form factor for greatest density per chassis
  • Hot-swappable input/output device that plugs into an Ethernet SFP+ port of a Cisco switch (no need to power down if installing or replacing)
  • Supports “pay-as-you-populate” model for investment protection and ease of technology migration
  • Digital optical monitoring capability for strong diagnostic capabilities
  • Optical interoperability with 10GBASE XENPAK, 10GBASE X2, and 10GBASE XFP interfaces on the same link (the same feature as the SFP-10G-LR-S=’s)
  • Cisco quality identification (ID) feature enables a Cisco platform to identify whether the module is certified and tested by Cisco (the same feature as the SFP-10G-LR-S=’s)

SFP-10G-LR-S= and X2-10GB-LR= are compatible as they have same specifications.

Cisco SFP+ Wavelength (nm) Cable Type Core Size (Microns) Modal Bandwidth (MHz*km)*** Cable Distance*
Cisco SFP-10G-LR-S 1310 SMF G.652 10km
Cisco X2-10GB-LR 1310 SMF G.652 10 km


Q2: SFP-10G-LR-S vs. SFP-10G-LR. What is (are) the difference(s) between the two optics?In particular what are the “unnecessary features” of the SFP-10G-LR-S? Can they be used in UA to Core deployment?

…The table below shows the key feature differences for the 10 Gbps S-class vs. C-class.

For UA to core campus applications, S-class is quite suitable.

C-Class S-Class
Multi-rate vs. Single-rate Multi-rate optics:

  • Ethernet
  • OTN
Single-rate optics:

  • Ethernet only
Operating temperature range
  • Commercial (0C to 70C)
  • Extended (-5C to 85C)
  • Industrial (-40C to 85C)
  • Commercial (0C to 70C) only

What’s your experience of using this Cisco S-class Optics and Non-S-Class Optics? Any sharing here will be appreciated…

More Related…

Cisco 10GBASE SFP+ Modules Overview

Cisco XFP vs. SFP vs. SFP+

About Transceiver & Cisco Transceiver Modules

The Questions about the Cisco 10GBASE X2 Module & SFP Compatibility

Cisco OneX Converter Module: the CVR-X2-SFP10G & CVR-X2-SFP10G=

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