Common Management Interface Specification (CMIS) defines, starting with revision 4.0, a standard mechanism for managing the firmware of compliant transceivers. This mechanism allows for transceivers’ firmware to be updated without having to remove the transceiver from the switch. Firmware updates may be necessary in a testing or production environment to resolve potential firmware bugs. Some transceivers may also support firmware management operations in a hitless manner (without impacting traffic).

Coherent transceivers, compliant with Coherent Common Management Interface Specification (C-CMIS) maintain two sets of thresholds to detect and report two types of link degradation: FEC excessive degrade (FED) and FEC detected degrade (FDD).

The intended purpose of this feature is to introduce a server streaming RPC. When a client subscribes to this RPC, they will receive a message anytime there is an update to the hardware programming state of an MPLS route or the Nexthop-Group to which it points to. Note that messages will only be streamed in this RPC callback for versioned MPLS routes that point to versioned nexthop-groups. Messages will not be streamed via this RPC for MPLS routes and Nexthop-Groups that don’t meet this criteria.

Configuration of arbitrary combinations of speeds on subinterfaces is being restricted on 800G CMIS Arista transceivers. This feature restricts configuring only uniform sets of speeds on applicable transceivers. This affects Arista-branded 800G active optical transceivers.

This feature introduces the ability to define matching rules to configure transceiver tuning on a switch. This is useful when a particular collection of transceivers are known to require tuning values which differ from EOS defaults.

Common Management Interface Specification (CMIS) compliant transceivers are configured by selecting an

In an optical transceiver, electrical signals leaving the switch are converted to optical signals in the transmit path. Optical signals arriving at the transceiver are converted to electrical signals that enter the switch in the receive path. At the point of conversion, an automatic decision can be made to turn off (squelch) output when the input level drops below a certain threshold of usability (usually, LOS condition.) This is referred to as automatic squelching.