IEEE 802.3cc-2017 pdf download

IEEE 802.3cc-2017 pdf download.IEEE Standard for Ethernet Amendment 1 1 : Physical Layer and Management Parameters for Serial 25 Gb/s Ethernet Operation Over Single-Mode Fiber
114.1.1 Bit error ratio
The bit error ratio (BER) shall be less than 5 × 10 –5 provided that the error statistics are sufficiently random that this results in a frame loss ratio (see 1.4.223) of less than 6.2 × 10 –10 for 64-octet frames with minimum interpacket gap when processed according to Clause 108. If the error statistics are not sufficiently random to meet this requirement, then the BER shall be less than that required to give a frame loss ratio of less than 6.2 × 10 –10 for 64-octet frames with minimum interpacket gap when processed according to Clause 108.
114.2 Physical Medium Dependent (PMD)service interface
The PMD service interfaces for 25GBASE-LR and 25GBASE-ER are the same as PMD service interface for 25GBASE-SR as described in 112.2 with the BER as specified in 114.1.1.
114.3 Delay constraints
An upper bound to the delay through the PMA and PMD is required for predictable operation of the MAC Control PAUSE operation. The sum of the transmit and receive delays at one end of the link contributed by the 25GBASE-LR or 25GBASE-ER PMD including 2 m of fiber in one direction shall be no more than 512 bit times (1 pause_quantum or 20.48 ns). A description of overall system delay constraints and the defini- tions for bit times and pause_quantum can be found in 105.5 and its references.
114.4 PMD MDIO function mapping
The optional MDIO capability described in Clause 45 defines several variables that may provide control and status information for and about the PMD. If the MDIO interface is implemented, the mapping of MDIO control variables to PMD control variables shall be as shown in Table 114–2 and the mapping of MDIO sta- tus variables to PMD status variables shall be as shown in Table 114–3.
114.5 PMD functional specifications
The 25GBASE-LR and 25GBASE-ER PMDs perform the Transmit and Receive functions, which convey data between the PMD service interface and the MDI. 114.5.1 PMD block diagram The PMD block diagram is shown in Figure 114–2. For purposes of system conformance, the PMD sublayer is standardized at the points described in this subclause.
The optical transmit signal is defined at the output end of a single-mode fiber patch cord (TP2), between 2 m and 5 m in length. Unless specified otherwise, all transmitter measurements and tests defined in 114.7 are made at TP2.
The optical receive signal is defined at the output of the fiber optic cabling (TP3) at the MDI (see 88.11.3). Unless specified otherwise, all receiver measurements and tests defined in 114.7 are made at TP3. TP1 and TP4 are informative reference points that may be useful to implementers for testing components (these test points will not typically be accessible in an implemented system).
114.5.2 PMD transmit function
The PMD transmit function shall convert the bit stream requested by the PMD service interface messages PMD:IS_UNITDATA.request into an optical signal stream. The optical signal stream shall then be delivered to the MDI, all according to the transmit optical specifications in this clause. The higher optical power level in the signal stream shall correspond to tx_bit = one.
114.5.3 PMD receive function
The PMD receive function shall convert the optical signal stream received from the MDI into a bit stream for delivery to the PMD service interface using the messages PMD:IS_UNITDATA.indication, all accord- ing to the receive optical specifications in this clause. The higher optical power level in the signal stream shall correspond to rx_bit = one
114.5.4 PMD global signal detect function
The PMD global signal detect function shall report the state of SIGNAL_DETECT via the PMD service interface. The SIGNAL_DETECT parameter is signaled continuously, while the PMD:IS_SIGNAL.indication message is generated when a change in the value of SIGNAL_DETECT occurs. The SIGNAL_DETECT parameter defined in this clause maps to the SIGNAL_OK parameter in the inter-sublayer service interface primitives defined in 105.4.IEEE 802.3cc pdf download.IEEE 802.3cc-2017 pdf download