RE: Newbie question on draft 2.1
Clause 49 is the 10GBASE-R PCS, not the WIS. Its output goes to the WIS
(clause 50) to create the WAN signalling. The PCS sends Local Fault
(LBLOCK_T) out the transmit link when the transmit state machine is in the
TX_INIT state. Local Fault (LBLOCK_R) is sent up the receive path when the
receive state machine is in RX_INIT state. Error blocks are generated when
errors are received that are not bad enough to send the receive state
machine into the RX_INIT state.
The WIS gets scrambled data and cannot send anything in the data stream. It
can use its fault primitive to tell the PCS above it that the WIS receiver
is in a fault state and it can use SONET overhead to tell the other side
when it can't transmit a good data stream.
The RS is general. It works with codings from the 10GBASE-R PCS and the
10GBASE-X PCS. The 10GBASE-R PCS puts in a full block of /E/ when it detects
an error because its encoding doesn't have a way to put in a mix of /E/ and
data characters. The 10GBASE-X PCS can put in /E/s one at a time. There
isn't any conflict here. Any frame with at least one error character is bad
and the RS will cause such frames to experience an FCS error.
From: Uyeshiro, Robin [mailto:Robin.Uyeshiro@spirentcom.com]
Sent: Tuesday, February 20, 2001 1:33 PM
Subject: Newbie question on draft 2.1
I'm violating the first law of reflectors here by asking a question before
listening for a while, but the deadline, an unsuccessful search of the
archive, and my confusion have forced the issue. I apologize if I offend.
The first question is about the Local Fault ordered set when using a WIS
(clause 49). The Link Fault Signaling state machine in the RS (clause 46)
responds to received Local Fault ordered sets, but I cannot see where these
are generated when using a WIS. The far end RS doesn't seem to transmit a
Local Fault ordered set (p.266), and I don't see anything in the WIS that
would put it on the receive path. Error blocks are generated, according to
the WIS Receive state machine, but not ordered sets. Could someone point me
in the right direction?
The second question concerns error blocks. The WIS defines EBLOCK_R as
having /E/ in all 8 character locations, but the PCS shows figure 46-8
Reception with error as a single byte of /E/ surrounded by frame data. Is
this simply an old figure 46-8?