Re: Interface reality check
Roy,
Break Link and Remote Fault are Ethernet constructs supported in Fast Ethernet
at well as Gigabit Ethernet.
For full-duplex links (i.e. all Gigabit and above Ethernet links as well as many
at lower speeds) it becomes increasingly important to completely remove a link
from operation when one direction is broken. Since there is no handshaking
proposed for 10 GbE protocol, even during initialization, and no
Auto-Negotiation is proposed, BL and RF control-codes are a great choice for the
implementation of these important Ethernet functions.
For further information on these functions and their specification, please see
standard IEEE 802.3.
Best Regards,
Rich
--
Roy Bynum wrote:
>
> Rich,
>
> Part of your specifications and the discussion resulting from your diagrams
> is that the AN functions that were in GbE would also be duplicated in 10GbE.
> You include "/RF/" and "/BL/" control codes as part the assumptions of your
> reference diagram. You are again taking for granted something that you
> acknowledge was not accepted by the HSSG. This type of "assumed"
> functionality is adding to the confusion of a lot of people. The issue of
> control codes, AN, etc.can be brought up again specifically as part of the
> LAN only PHY at the next meeting. In the mean time, other control codes
> have not been defined as yet originating from the MAC for P802.3ae. At
> present, only "normal interframe"(/i/), "valid data" (/d/), and "error"(/e/)
> can be assumed as the requirements for the RS.
>
> Thank you,
> Roy Bynum
>
> --
>
> > Roy,
> >
> > I am fully aware that not only is Auto-Negotiation not included in
> > P802.3ae objectives, that a motion I made proposing AN for 10 GbE
> > in September, 1999 failed miserably. As usual, I get over my failed
> > motions rather quickly.
> >
> > If you have an issue with AN, please bring it up. From my perspective, it
> > has no bearing on this thread.
> >
> > Non support of AN in 10 GbE has no bearing on the independent requirements
> > to support Remote Fault and/or Break Link functionality in 10 GbE. That
> > was the thread being discussed.
> >
> > BTW: is support of these functions being considered by proponents of a
> > pure scrambled code over all proposed 10 GbE interfaces and sublayers
> > and for all proposed PHY variants?
> >
> > Best Regards,
> > Rich
> >
> > --
> >
> > Roy Bynum wrote:
> > >
> > > Rich,
> > >
> > > If you will re-examine the objectives, you will discover that
> > > Auto-Negotiation is not supported by P802.3ae.
> > >
> > > Thank you,
> > > Roy Bynum
> > >
> > > --
> > > >
> > > > Roy,
> > > >
> > > > In GbE, Remote Fault and Break Link are both signaled during
> > > > Auto-Negotiation (AN). For 1000BASE-X GbE, AN is a management
> > > > function that executes mutually exclusively with normal PCS
> > > > functions. AN is specified in 1000BASE-X clause 37 while the
> > > > PCS is specified in clause 36. GbE AN control input is from
> > > > management, not the RS. GbE AN functions "take over" the GbE PCS for
> > > > use as an AN transport. The GbE MAC, RS, management, AN and PCS
> > > > functions are typically integrated.
> > > >
> > > > My RS proposal simply has the RS receiver treating all control codes
> > > > not specified by 802.3ae to have special meaning as Idle. This rule
> > > > would apply to every RS receiver.
> > > >
> > > > Best Regards,
> > > > Rich
> > > >
> > > > --
> > > >
> > > > Roy Bynum wrote:
> > > > >
> > > > > Rich,
> > > > >
> > > > > Please explain. The "remote fault" and "break link" indicators that
> are
> > > > > in GbE, are these transmitted from the RS to the PCS as part of the
> RS
> > > > > information, or are these transmitted from the PCS to the RS during
> the
> > > > > "non-data" periods of received data?
> > > > >
> > > > > I am confused. When you say that the RS translates the 8B10B
> encoding
> > > > > idle characters into an /I/, are you referring to it happening
> within
> > > > > the same box or are you saying this will happen at the remote box
> that does not
> > > > > have XAUI?
> > > > >
> > > > > Thank you,
> > > > > Roy Bynum
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