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DKM CWDM Mux/Demux, 4 Port, Fiber Wave Divison Multiplexor

Get 4 Times the trafic over a Fiber Cable


Limited Quantity In Stock
Typically Ships within One Week
Extended Double Diamond™ Warranty Available (3 Additional Year)

*Required field

Product Features

  • Extend single-mode fiber runs up to 40 kilometers (25 mi.).
  • Combines and sends four bidirectional data streams simultaneously over a single fiber pair!
  • Use in pairs. The second unit demuxes the combined signal for output to four remote devices.


  • Enables you to economically make better use of long-distance fiber runs.
  • Great for industrial and electronically noisy areas, and high-security government applications.
  • Can be used with KVM extenders to link four CPUs to four remotely located KVM consoles.
  • Equipped with LC connectors for input/output of fiber channels at varying wavelengths.
  • Data is not affected at either end.
  • Order along with separately available plug-in SFP transceivers to suit your fiber requirements.
  • No power supply required.
  • Small footprint chassis.

  • This fiber-based ServSwitch™ extension device combines four separate optical carrier channels for cost-effective extension over one fiber pair. Expand your network capacity and reach—without pulling new fiber runs!

    Using coarse wavelength division multiplexing (CWDM), the mux/demux combines the different signals into a light prism for laser transmission across a 9-/125-µ single-mode fiber link.

    And with compatible ServSwitch KVM extenders, the mux/demux units enable you to put four workstation consoles at a greater distance from local CPUs and connect them all over a single fiber.

    You can also use the mux/demux units by themselves to extend high-bandwidth data, video, or voice, as well as Fiber Channel services for LAN and SAN connectivity. They're also useful for any campus extension application in corporate, education, or healthcare environments.

    ServSwitch Fiber CWDM Mux/Demux is particularly ideal for hospitals looking to make better use of existing fiber. Use it, for example, to link separate outpatient offices to a core network node in a main hospital building. Because it uses fiber, you can get the bandwidth you need for shared applications, as well as help ensure data security for sensitive patient records.

    And by using a single fiber pair for 4:1/1:4 extension, you can not only limit the number of long-distance fiber runs in your building or on your campus, but you can reduce associated maintenance and troubleshooting costs, too.

    How it works
    The ACXCWDM4 comes as a pair of CWDM Mux/Demux units.

    The first unit mixes the signals in different wavelengths onto the fiber cable. The second unit splits (demultiplexes) it into the original signals at the end of a link. The separate optical signals can be used to connect four remote workstations, servers, or client applications.

    You will have to also order compatible transceiver units (separately available). In all, you'll need four of these Gigabit-speed SFP transceivers for the local (source-side) optical input and four SFP transceivers for the remote side.

    The mux/demux interfaces with the four SFP transceivers via four color-coded LC duplex connectors. The transceivers operate on their own channel wavelength, with each color-coded channel spaced 20 nm apart in 1530-nm, 1550-nm, 1570-nm, or 1590-nm increments at speeds up to 1.25 Gbps.

    This product works with:
  • SFP, 1.25 Gbps Fiber (CWDM), 1530-nm Single-Mode, SC, 70 km (LFP254)
  • SFP, 1.25 Gbps Fiber (CWDM), 1550-nm Single-Mode, SC, 70 km (LFP255)
  • SFP, 1.25 Gbps Fiber (CWDM), 1570-nm Single-Mode, SC, 70 km (LFP256)
  • SFP, 1.25 Gbps Fiber (CWDM), 1590-nm Single-Mode, SC, 70 km (LFP257)
  • ServSwitch DKM DVI-D KVM Switches (ACX0808, ACX0816, ACX0832, ACX1616, ACX1632, ACS4001A-R2)
    Questions? Contact our FREE Tech Support.

    NOTE: Each wavelength (1530, 1550, 1570, 1590 nm) must not be used more than once on each side.

  • Tech Specs

    CE Approval Yes
    Connectors Each unit: (4) pairs of LC
    Operating Environment Temperature: 41° to 113° F (5° to 45° C) Humidity: 80%, noncondensing
    Power None required
    RoHS Yes
    Size 18.1"H x 9.8"W x 4.7"D (46 x 24.9 x 11.9 cm)
    Weight 3.5 lb. (1.6 kg)
    This product works with:
    Each wavelength (1530, 1550, 1570, 1590 nm) must not be used more than once on each side.

    * Technical specification weight is the unit weight. It is not the packaged shipping weight. For shipping weight, please contact Black Box customer service at 877-877-2269.



    Double Diamond Warranty

    Extended 1 Year Warranty Available

    Protect your purchase with an additional 1 Year Double Diamond™ warranty!
    Cost: $284.85

    Extended 3 Year Warranty Available

    Protect your purchase with an additional 3 Year Double Diamond™ warranty!
    Cost: $569.69


    Double Diamond™ Warranty (Standard)

    Take the risk out of equipment purchases with the Double Diamond™ Warranty from Black Box Network Services.

    The Double Diamond Warranty is our warranty that protects your Black Box® brand products* from accidental damage, including drops, water, and power surges.

    The CWDM Mux/Demux, 4 Port, Fiber Wave Divison Multiplexor comes with a standard 2 Year Double Diamond™ Warranty (Standard) already included.

    During the warranty period, Black Box Network Services will repair or replace your damaged equipment within one week of receipt at NO CHARGE!*

    Plus, get an Extended Double Diamond Warranty.

    You can also extend your warranty or protect a previously purchased Black Box® brand product** for an additional year—for only 10% of the purchase price! Or, extend your coverage for a full three years for only 20% of the purchase price!

    Ordering an extended warranty is easy: When viewing a product in your shopping cart, just select the one or three years of additional coverage in the dropdown menu under “Warranty Options.” For details, contact Customer Service at 724-746-5500.

    * Warranty subject to certain exclusions and limitations ** Certain products may not be eligible.

    What’s more, we also have a 45-day return policy. Simply call Customer Service for a Return Authorization (RA) number, return your product in new condition and in the original package, and receive a full refund.