Sfp+ Transceiver Slots On The At-X550-18Xsq And At-X550-18Xspqm Switches; Sfp And Sfp+ Transceivers; Leds; Figure 7: Link And Activity Leds For The 1Gbps Sfp And 10Gbps Slots On The At-X550-18Xsq And At-X550-18Xspqm Switches - Allied Telesis x550 Series Installation Manual

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

LEDs

The AT-x550-18XSQ and AT-x550-18XSPQm Switches have sixteen and
eight slots, respectively, for SFP or SFP+ transceivers.
The slots 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 SFP+ transceiver slots 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.
This section applies to the 1Gbps SFP and 10Gbps SFP+ transceiver slots
on the AT-x550-18XSQ and AT-x550-18XSPQm Switches. Each
transceiver slot has one LED. The LEDs are located between the slots.
Refer to Figure 7.
Top Transceiver Slot LED
Figure 7. Link and Activity LEDs for the 1Gbps SFP and 10Gbps Slots on
the AT-x550-18XSQ and AT-x550-18XSPQm Switches
x550 Series Installation Guide for Stand-alone Switches
Bottom Transceiver Slot LED
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