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I have a use case where I am attempting to establish a unidirectional Ethernet link where a singular fiber is used to transmit data to the receiver. The Rx of the transmit side and the Tx of the receive side are not physically connected.

The proposed configuration is as follows:

  • The PHY is a fiber optic 1000BASE-X (LX or SX)
  • Autonegotiation and any link monitoring protocols are disabled
  • Full duplex configuration
  • A second transceiver on the low (transmitting) side is used to provide a connection to the Rx port on the transceiver attempting to transmit unidirectionally (Ethernet spoofing) to set the signal_detect variable in the PCS
  • UDP is the transport protocol and ARP is statically configured

So the question is will this configuration allow for successful synchronization at the PHY level for the transmitting side, i.e. will this "Ethernet spoofing" allow the second transceiver to provide the /Comma and /Idle code groups to the first that are required to achieve synchronization? Does synchronization need to be established on the high (receiving) side to successfully receive data?

Alternatively, will COTS SFP transceivers support IEEE 802.3 Clause 66, i.e. setting the mr_unidirectional_enable PCS variable, if the PHY is not of the passive optical network type and an OAM sublayer is not present?

I'm aware of security appliance data diodes however am trying to avoid that implementation. Thanks.

Quiet
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