Sfp+ Transceiver Ports On The At-X550-18Xsq And At-X550-18Xspqm Switches; Sfp And Sfp+ Transceivers; Leds; Figure 7: Link/Activity Leds For 1/10Gbps Transceiver Ports 1 To 16 On The At-X550-18Xsq Switch And Ports 9 To - Allied Telesis AT-x550-18XTQ Installation Manual

SFP+ Transceiver Ports on the AT-x550-18XSQ and AT-x550-
18XSPQm Switches
SFP and SFP+
Transceivers

LEDs

Transceiver ports 1 to 16 on the AT-x550-18XSQ Switch and ports 9 to 16
on the AT-x550-18XSPQm Switch support SFP and SFP+ transceivers.
The ports support the following types of transceivers:
 1Gbps SX/LX SFP transceivers
 10Gbps SR/LR SFP+ fiber optic transceivers
 10Gbps AT-SP10TW direct connect twinax cables with SFP+
transceiver-style connectors
Guidelines for the ports are listed here:

They do not support 100Mbps-FX transceivers.

They support full-duplex mode only.

You can set the port speeds with Auto-Negotiation or manually.
The default is Auto-Negotiation.
SFP or SFP+ transceivers must be purchased separately. For a list of
supported transceivers, refer to the product data sheet on the Allied
Telesis web site.
Each transceiver port has one LED. The LEDs are located between the
ports. Refer to Figure 7.
Top Transceiver Port LED
Figure 7. Link/Activity LEDs for 1/10Gbps Transceiver Ports 1 to 16 on the
AT-x550-18XSQ Switch and Ports 9 to 16 on the AT-x550-18XSPQm
x550 Series Installation Guide for Virtual Chassis Stacking
Bottom Transceiver Port LED
Switch
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