Fiber SFP Modules



  • I am reviewing some information on SFP modules and connections. I am not a guru when it comes to fiber modules and their protocols.

    But I wanted to see if someone could explain to me the use behind a CWDM module and a Standard Base modules? I noticed that CWDM modules have multiple wave lengths, but I am not 100% sure what the use would be for 16-18 wave lengths.

    Would a CWDM module be used for basic setup of fiber between two buildings?

    Thanks for the insight.



  • You do not need CWDM SFP modules for basic networking.

    What this really comes down to is what you need.

    For example, Ubiquiti sells a basic SFP and SFP+ module on the 850nm wavelength. But they are only rated for 550m and 300m respectively.

    The CWDM varieties are all 1Gbps and on specific wavelengths. So you just need to make sure you have the same model on each end.

    0_1540929644469_d5ef2647-1548-4125-bf3e-fd2c4aa3ad47-image.png

    To keep things simple, you basically always want to buy in pairs, no matter your application.



  • CWDM are using several different light wavelengths at the same time to get higher throughput. Basically like having several different fiber transmissions going on in the same fiber at the same time.

    It's not really needed anymore for 1 or 10 Gigabit.

    There are two types of fiber - multi-mode fiber (MMF) and single-mode fiber (SMF). Single mode fiber is the better one and the one you should install today.

    With single mode fiber you can transfer 10 Gigabit just using two 10GBASE-LR SFP+ modules for a distance of up to 10 kilometers, 6 miles. The same fiber can also be used for gigabit as well as faster rates like 100 Gigabit.



  • @Pete-S

    Great info thanks! So does Single Mode only use a BiDi connector or can it use a Duplex? Same for Multi-Mode?
    Duplex does the transmission TX and RX go in their own respective lines of fiber?



  • @Pete-S said in Fiber SFP Modules:

    CWDM are using several different light wavelengths at the same time to get higher throughput. Basically like having several different fiber transmissions going on in the same fiber at the same time.

    It's not really needed anymore for 1 or 10 Gigabit.

    There are two types of fiber - multi-mode fiber (MMF) and single-mode fiber (SMF). Single mode fiber is the better one and the one you should install today.

    With single mode fiber you can transfer 10 Gigabit just using two 10GBASE-LR SFP+ modules for a distance of up to 10 kilometers, 6 miles. The same fiber can also be used for gigabit as well as faster rates like 100 Gigabit.

    I had no idea you could get 10 Gig that far on Single Mode.

    Do you know what the distances are for Multimode?



  • @dafyre said in Fiber SFP Modules:

    @Pete-S said in Fiber SFP Modules:

    CWDM are using several different light wavelengths at the same time to get higher throughput. Basically like having several different fiber transmissions going on in the same fiber at the same time.

    It's not really needed anymore for 1 or 10 Gigabit.

    There are two types of fiber - multi-mode fiber (MMF) and single-mode fiber (SMF). Single mode fiber is the better one and the one you should install today.

    With single mode fiber you can transfer 10 Gigabit just using two 10GBASE-LR SFP+ modules for a distance of up to 10 kilometers, 6 miles. The same fiber can also be used for gigabit as well as faster rates like 100 Gigabit.

    I had no idea you could get 10 Gig that far on Single Mode.

    Do you know what the distances are for Multimode?

    I think it depends on the fiber and transceivers used and the speed but from 100ft to 1000ft.

    Multimode used to be what everybody was installing but haven't seen it used in anything new the last 5 years or so. I'm not familiar with prices but they tell me that the price of the complete installation with either fiber type will be virtually the same. In the past single mode was a lot more expensive.

    PS. You can do 100 Gigabit as well over the same distance (10km/6 miles) with single mode.



  • @TX1TGUY said in Fiber SFP Modules:

    @Pete-S

    Great info thanks! So does Single Mode only use a BiDi connector or can it use a Duplex? Same for Multi-Mode?
    Duplex does the transmission TX and RX go in their own respective lines of fiber?

    Have a look at this to see what is commonly available: https://www.fs.com/c/fiber-optic-transceivers-9

    Most single mode installations I've seen are using duplex, one fiber for transmitting and one for receiving. So a pair of fibers are used for each transmission line.



  • @Pete-S said in Fiber SFP Modules:

    @dafyre said in Fiber SFP Modules:

    @Pete-S said in Fiber SFP Modules:

    CWDM are using several different light wavelengths at the same time to get higher throughput. Basically like having several different fiber transmissions going on in the same fiber at the same time.

    It's not really needed anymore for 1 or 10 Gigabit.

    There are two types of fiber - multi-mode fiber (MMF) and single-mode fiber (SMF). Single mode fiber is the better one and the one you should install today.

    With single mode fiber you can transfer 10 Gigabit just using two 10GBASE-LR SFP+ modules for a distance of up to 10 kilometers, 6 miles. The same fiber can also be used for gigabit as well as faster rates like 100 Gigabit.

    I had no idea you could get 10 Gig that far on Single Mode.

    Do you know what the distances are for Multimode?

    I think it depends on the fiber and transceivers used and the speed but from 100ft to 1000ft.

    Multimode used to be what everybody was installing but haven't seen it used in anything new the last 5 years or so. I'm not familiar with prices but they tell me that the price of the complete installation with either fiber type will be virtually the same.

    I use muiltimode for in-building connections. cheap and easy and available up to 10Gbps.

    For inter-building connections on a larger campus, I would recommend single mode.


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