Re: XAUI and 64b/66b
Actually, the MII and GMII do "speak IDLES". Please
refer to 126.96.36.199 (for the MII) and 188.8.131.52 (for the GMII),
which describe the "inter-frame" period. 184.108.40.206 is reproduced
in its entirety below:
The inter-frame period provides an observation window for an
unspecified amount of time during which no data activity occurs
on the MII. The absence of data activity is indicated by the
de-assertion of the RX_DV signal on the receive path, and the
de-assertion of the TX_EN signal on the transmit path. The MAC
interFrameSpacing parameter defined in Clause 4 is measured
from the de-assertion of the CRS signal to the assertion of
the CRS signal.
For the XGMII, we have proposed using "embedded delimiters", rather
than discrete signals like RX_DV and TX_EN to indicate the transition
between the inter-frame period and the preamble/sfd/data/efd phases.
That is why we refer to an XGMII code point named "IDLE". This
code point is nothing more than the way the inter-frame period is
conveyed across the XGMII, in the absence of discrete signals.
Cisco Systems, Inc.