S6120 Series

Stand-alone DS1 – T1/E1/J1 Network Interface Device
4 x DS1 – T1/E1/J1 + 10/100 Ethernet over Fiber

S6120 Series
  • S6120-Series
  • S6120
  • S6120-1014
  • S6120-1040

The ION S6120 is a managed stand-alone DS1 – T1/E1/J1 mux that provides a solution for those users that need to extend multiple DS1 – T1/E1/J1 connections, along with a 10/100 Ethernet connection, all over fiber. The S6120 includes (4) RJ-48 ports, (1) 10/100 Ethernet port, and (1) fiber port. The device is available in versions that support fixed fiber connectors as well as SFP fiber modules offering support for a variety of fiber types, distances, and wavelengths to provide maximum flexibility across a variety of network topologies. CWDM SFPs can also be utilized to further increase the bandwidth capacity of the fiber infrastructure.

The S6120 converter must be used in pairs. Management of the stand-alone converter is supported, in-band, over the fiber, when the remote S6120 is linked to a C6120 card installed in a managed ION chassis.

S6120 Series

Related Products

S6120 Series Overview


  • (4) RJ-48 copper interfaces
  • (1) fiber interface (fixed or SFP)
  • (1) RJ-45 10/100Mbps Ethernet port
  • Auto-MDI/MDIX
  • Pause (Flow Control on Ethernet port)
  • Loopback via test set
  • Local and remote loopbacks
  • LEDs for device status and troubleshooting
  • Settings for line code, line build out, loopbacks and Alarm Indication Signal (AIS)
  • Access to complete status and configuration on local and remote device
  • Remote firmware upgrade
  • Remote management
  • Extended operating temperature
  • Must be used in pairs

S6120 Series Tech Specs


    • ANSI T1.102
    • T1.403 and T1.408
    • ITU I.431
    • G.703
    • G.736
    • G.775
    • G.823
    • ETSI 300-166
    • 300-233
    • TBR 12/13
    • AT&T Pub 62411
    • IEEE 802.3

    Data Rate

    • Copper ports (RJ-48): T1(J1) = 1.544Mb/s,
    • E1 = 2.048Mb/s
    • Ethernet port (RJ-45): 10/100Mbps
    • SFP port(s) (empty): 100Base-X/OC-3


    • Numerous switch settings for line coding, line build out, loopback and AIS

    Status LEDs

    • Power, Port Status, Loopback and AIS


    • Width: 3.7” [94 mm]
    • Depth: 6.5” [165 mm]
    • Height: 1.8” [46 mm]

    Power Consumption

    • 6 Watts (max) for dual fiber model
    • 5.5 Watts (max) for single fiber model

    Power Input

    • AC: 12 VDC via barrel connector using 100-240VAC, UL listed power supply


    • Operating: -10°C to 65°C
    • Storage: -40°C to 85°C
    • Humidity: 5% to 95% (non-condensing)


    • 2 lbs. [0.90 kg]


    • 114,580 hours (Bellcore)


    • EN55022 Class A, EN55024, CE mark


    • Lifetime

S6120 Series Resources

Application Spotlights
Press Releases
Case Studies

S6120 Series Downloads

Note: Some Documentation may have Transition Networks named or pictured. Transition Networks was acquired by Lantronix in August 2021. Learn more about the acquisition here.


Firmware Downloads

S6120 Series Firmware, Release Notes and MIBs

S6120 Series Part Numbers

S6120-1013 S6120 Series

1300nm multimode (SC) [2 km/1.2 mi.] Link Budget: 11.0 dB to (4) RJ-48 [1.5 km/0.9 mi.] + 10/100Base-TX (RJ-45) [100m]

S6120-1014 S6120 Series

1310nm single mode (SC)[20 km/12.4 mi.] Link Budget: 16.0 dB to (4) RJ-48 [1.5 km/0.9 mi.] + 10/100Base-TX (RJ-45) [100m]

S6120-1040 S6120 Series

1 *SFP port (Empty) to (4) RJ-48 [1.5 km/0.9 mi.] + 10/100Base-TX (RJ-45) [100m]

Lantronix Part # Name Description Order Now

*SFP port uses standard 100Base-x/oc-3 SFP

Compatible Accessories

Lantronix Part # Legacy Part # Name Description Order Now
SFP Modules SFP Modules See Relevant SFP Modules
SPS-2460-SA SPS-2460-SA Stand-Alone Power Supply
WMBL WMBL 4″ Wall Mount Kit (long)