Choosing a 10GBASE-SR SFP Module

Start with the installed fibre

The first step is to identify the multimode fibre grade already installed on the link, because the grade decides the maximum distance for any SR module on that link. The grade is usually recorded in the installation documentation, and it is also marked on the fibre itself; where neither is available, the grade can be established by inspection or by planning for the shorter reach. Skipping this step and ordering on a distance figure alone is the most common cause of SR links that fail at installation, because the distance figure belongs to a grade that may not be the installed one.

Older buildings deserve extra care here. An installation that predates current fibre grades may carry a lower grade than the buyer assumes, and a module ordered against a modern grade figure will not reach on that older fibre. Where the building age or the installation date suggests older fibre, state that in the enquiry and ask for the reach to be confirmed against each candidate grade, so the order can be placed once the grade is confirmed rather than after a failed installation.

Then the distance, honestly measured

The second step is the actual link length, measured along the installed route including patch cords and any intermediate distribution frames, not the straight-line distance between the two endpoints. Patch cords, slack loops and routing around obstacles add length that a straight-line estimate misses, and a link that looks short on a floor plan can be materially longer once installed. Measure the route, add the patch cords, and compare the total against the reach for the installed grade.

Where the measured length is close to the reach limit for the installed grade, the margin matters. A link at the edge of the listed reach leaves no room for additional connectors, for future re-routing or for measurement error, and a small change in the route can push it outside specification. In that case the safer choice is either a higher-grade fibre run or a single-mode module, and the decision should be made before ordering rather than after the link is installed and tested.

Then the host platform

The third step is the host platform, because host acceptance is tested per module and a module that matches optically can still be rejected by a host that does not accept it. Name the switch, router or server card model in the enquiry when compatibility matters, and ask for compatibility to be confirmed for that combination. Do not assume that a module listed for one platform works on another, and do not assume that a module in the same form factor family is accepted by the same host.

Compatibility is also where the distinction between original and compatible modules matters. A compatible module is built to work in a named host platform without being the original product of that platform's brand owner, and the two are different purchases even when the optical figures look similar. State in the enquiry whether an original product or a compatible module is required, because the answer changes the product and the price, and an order placed without that distinction may deliver the wrong one.

What a complete SR SFP enquiry contains

A complete enquiry names the rate, the installed fibre grade, the measured distance including patch cords, the connector, the host platform, the quantity and the environment. Each item removes a round of questions, and together they usually allow a quotation and a compatibility confirmation without further correspondence. An enquiry that names only the rate, or only a module-style name, will need at least one further round, because none of the other items can be inferred from the rate alone.

Environment is the item most often omitted and most often regretted. The listed temperature range for a module covers ordinary indoor conditions, and links in unconditioned spaces, in roof voids or in outdoor enclosures fall outside that range. State the environment when it is not an ordinary indoor data center or wiring closet, so the temperature grade can be confirmed as part of the order rather than discovered as a failure in summer or winter.

Why this article ends in an enquiry

This article ends in an enquiry because no SR SFP module with a listed specification is published on this site. Short-reach titles appear in the source material at title level only, and title figures are not specifications: a title does not state the fibre grade, the connector, the temperature range or the host compatibility, and ordering against a title figure is ordering against an incomplete specification. The enquiry route is not a delaying tactic; it is the route by which the missing figures are confirmed per model before an order is placed.

That discipline is applied consistently across this site. Lines with a listed specification have product pages, and lines without one have category or guide pages that explain the line and route the buyer to an enquiry. A buyer who understands that boundary will never be misled by a title figure, and will always know which figures are published and which figures still need confirming.

Before you send the enquiry

A good enquiry for any topic in this article names the rate, the wavelength, the fibre type, the distance, the connector, the quantity and the application, plus the host platform when compatibility matters and any certification document needed by name. Each item removes a round of questions, and together they usually allow a quotation and a compatibility confirmation without further correspondence. An enquiry that names only a rate, or only a module-style name, will need at least one further round, because none of the other items can be inferred from the rate alone.

Environment and quantity also belong in the first message. Quantity affects the quotation and the delivery schedule, and environment matters because the listed temperature range for a module covers ordinary indoor conditions; links in unconditioned spaces, in roof voids or in outdoor enclosures fall outside that range and should be raised explicitly. Stating the environment when it is not an ordinary indoor data center or wiring closet lets the temperature grade be confirmed as part of the order rather than discovered as a failure in summer or winter.

Finally, check whether the line you need has a product page on this site or only a guide page. A product page carries a listed specification for a specific model, and an enquiry against it can confirm price, stock and compatibility for that model. A guide page explains the line and routes you to an enquiry, because no listed specification exists for that line here. Knowing which of the two you are reading prevents the most common buying mistake on this site, which is treating a guide figure, a title figure or a standard figure as if it were a specification for a specific module.

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.