Single Mode vs Multimode Transceivers: Choosing by Link
Single-mode and multimode are fibre types, not module brands, and the choice between them is decided by distance, installed fibre and cost rather than by preference. This application page explains the choice using only the figures listed on this site, so that a buyer can see which of the two families fits a link without borrowing figures from a standard or a neighbouring model.
What this page covers
This page is a application page for single-mode against multimode choice. It gathers the models and guidance that belong to this line in one place, and it links to the individual product pages where a model has a listed specification. Lines that have only a title-level mention, with no detailed specification behind them, are described here at category level only and are not given a product page, because a product page without a listed specification would be guessing.
The distinction matters for buying. A category page answers which line a need belongs to and what to ask about; a product page answers the listed figures for one model. If you arrive here looking for a figure for a specific model, follow the link to that model page, and if no model page is linked, the figure is not published on this site and should be asked for in the enquiry rather than inferred from a neighbouring model.
How to specify this line
A usable enquiry for single-mode against multimode choice starts with the rate, the wavelength, the fibre type and the distance, because those four items decide whether a module fits the link at all. The connector and the form factor come next, followed by the operating temperature range and whether digital diagnostics are required. Buyers who send only a rate, or only a model-style name, usually need a second round of questions before a quotation can be confirmed, so including the full set in the first message saves a cycle.
Distance figures deserve special care. A distance quoted for one fibre type does not transfer to another, and a distance quoted for one wavelength does not transfer to a different wavelength. On this site every distance is tied to the fibre and wavelength it was listed with, and where the source pages disagree the conflict is flagged on the page. If a distance matters for your link, name the fibre you will actually install and ask for the figure to be confirmed against that fibre before ordering.
What to confirm before ordering
Before an order is placed, confirm the model, the rate, the wavelength, the distance, the connector and the quantity in writing, and confirm any certification document you need by name. Minimum order quantity and lead time are unavailable at company level on this site, so ask for both per model in the enquiry rather than assuming a company-wide term. Quotations are confirmed per order, and specifications are confirmed per model before payment.
Compatibility is a separate check from the optical figures. A module that matches on rate and wavelength can still fail on a host platform that does not accept it, so name the host platform in the enquiry when compatibility matters. Where this site states a compatibility position, it states the source of that position, and it does not extend a compatibility statement from one model to another. If the platform is not named, compatibility cannot be confirmed from this page alone.
What the listed figures show
On this site, the multimode figure is the 40G module at 850nm, listed at up to 100m on OM3 fibre and up to 150m on OM4 fibre. The single-mode figures are the 1.25G bidirectional module at up to 25km, the 10G module at 10km, the 100G CWDM4 module at up to 2km, and the 400G module at up to 500m. The pattern is clear: multimode serves short in-building links, and single-mode serves everything longer, with the exact single-mode distance depending on the module rather than on the fibre family alone.
The common mistake is to treat single-mode as automatically long-reach in every case. A 500m 400G single-mode module and a 25km bidirectional single-mode module are both single-mode, yet their reaches differ by a factor of fifty, because reach is a property of the module design and not of the fibre family. Always read the distance off the specific product page, and never infer a distance from the words single-mode or multimode alone.
Models on this page
QSFP 40G SR4 Module
40G multimode module at 850nm.
SFP 10G LR Module
10G single-mode SFP compatible module over 10km.
QSFP 100G CWDM4 Module
100G single-mode CWDM4 module over up to 2km.
400GBASE-DR4 QSFP-DD Module
400G single-mode module over up to 500m.
Enquiry checklist
Before sending an enquiry, note the model or the rate you need, the wavelength, the fibre type, the distance, the connector, the quantity and the application. State whether the module must be compatible with a named host platform, and name any certification document you need. Minimum order quantity and lead time are unavailable at company level and are confirmed per model in the enquiry. Quotations are confirmed per order.
Send an enquiry | Sales contact: Ms. Vicky Tian, Sales Manager, +86 19860146913 | Telephone: 86-0755-82552969 | Email: dsale@topsfp.com
Frequently asked questions
How do I get a quotation?
Send an enquiry naming the model, the rate, the wavelength, the distance and the quantity you need, plus the application. Quotations are confirmed per order, and specifications are confirmed per model before payment. This site does not list fixed selling figures, and no price is shown for any model.
What certification documents can you provide?
The company states ISO 9001, CE, FC, 3C and RoHS names. Certificates are available upon request. If a buyer needs a certificate for a specific model, name the model in the enquiry so the correct document can be checked. No certificate numbers are published on this site.
Do the specifications on one page apply to the whole range?
No. Specifications are shown per model and must not be read across the whole range. Where a value is not listed for a model, the page says to confirm per model rather than filling in a generic figure, and where the source pages disagree, the page flags the conflict instead of choosing one value as fact.
What are the minimum order quantity and lead time?
At company level both are unavailable on this site and are confirmed per model in the enquiry. A single-model note, where one exists, is marked as applying to that model only and must not be read as a company-wide term.