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RE: [EFM] EFM-OAM frame fomat




Matt, Geoff

Just a point of clarification: Are slow protocols, such as that used by 
OAM, also restricted relative to use with VLAN Tags?

Thank you,
Roy Bynum

At 11:03 AM 9/18/03 -0400, Matt Squire wrote:



>Then I misunderstood what we were talking about.  The question I heard was 
>whether OAM frames (and slow protocols in general)  can be LLC 
>encapsulated.  According to C43B, 43B.3 and 43B.4, the slow protocols 
>EtherType must be in the Length/Type field of the Ethernet frame.
>
>If you're saying that slow protocols aren't intended for hardware 
>processing, then I'd say maybe.  Certainly MAC control are intended for HW 
>processing only.  Slow protocols could be done in either way (some people 
>have done OAM in HW, or LACP in HW).
>
>So I agree that the justification for the slow protocols is not so that 
>they can be processed in HW - just the opposite.  However, the 'catching' 
>of slow protocols (e.g. identifying them as special) is intended for HW, 
>and thats where the my comment on requiring them to use the special MAC 
>address and Lenghth/Type value of 88-09 instead of allowing LLC encaps, 
>SNAP stuff, and any other encapsulation, is prohibited.
>
>But in the end, its not that important.
>
>
> > -----Original Message-----
> > From: Geoff Thompson [mailto:gthompso@nortelnetworks.com]
> > Sent: Thursday, September 18, 2003 12:13 PM
> > To: Matt Squire
> > Cc: Alan Weissberger; Shahram Davari; stds-802-3-efm@ieee.org
> > Subject: Re: [EFM] EFM-OAM frame fomat
> >
> >
> >
> > Matt-
> >
> > I believe that you are incorrect.
> > The reason for the "Slow Protocol" being differentiated from
> > the original
> > MAC Control Frame used for "PAUSE" is that PAUSE Frames have
> > to be caught
> > in hardware, Slow Protocol frames are candidates for software
> > handling.
> >
> > Geoff
> >
> >
> > At 07:27 PM 9/15/2003 -0400, Matt Squire wrote:
> >
> >
> > >Just to second Alan, the slow protocols cannot be LLC
> > encapsulated or
> > >802.3Q encapsulated or anything else.  They are a native
> > ethernet protocol
> > >with a single encapsulation intended for (some) potential
> > processing in
> > >hardware.
> > >
> > >- Matt
> > >
> > >
> > >-----Original Message-----
> > >From: Alan Weissberger <ajwdct@technologist.com>
> > >Sent: Sep 15, 2003 1:33 PM
> > >To: Shahram Davari <Shahram_Davari@pmc-sierra.com>,
> > stds-802-3-efm@ieee.org
> > >Subject: Re: [EFM] EFM-OAM frame fomat
> > >
> > >
> > ><P>Shahram</P>
> > ><P>I don't believe an Ethernet OAM frame can be sent with LLC
> > >embedded.  My understanding is that the Type field= Slow
> > protocol frame,
> > >which precludes carrying embedded LLC PDU. In other words,
> > the OAM PDU is
> > >self contained and there is no LLC or higher layer carried
> > within the user
> > >data field</P>
> > ><P>Hence, it is not possible to have the last 2 Ethernet
> > frame formats
> > >carry an OAM frame:</P>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003>- 802.3 + LLC
> > >(802.2)</SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003>- 802.3 + LLC
> > >+SNAP</SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003></SPAN></FONT>
> > ></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > >class=015465616-15092003>Rgds</SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003></SPAN></FONT>
> > ></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > >class=015465616-15092003>alan</SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003><PRE>Alan
> > >Weissberger</PRE><PRE>DCT
> > >2013 Acacia Ct
> > >Santa Clara, CA 95050-3482
> > >1 408 863 6042 voice
> > >1 408 863 6099 fax</PRE></SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003></SPAN></FONT>
> > ></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003></SPAN></FONT>
> > ></DIV>
> > ><P><BR><BR>----- Original Message -----<BR>From: Shahram Davari
> > ><SHAHRAM_DAVARI@PMC-SIERRA.COM><BR>Date: Mon, 15 Sep 2003 10:02:33
> > >-0700<<BR>To: stds-802-3-efm@ieee.org<BR>Subject: [EFM]
> > EFM-OAM frame
> > >fomat<BR><BR></P>
> > ><META content="MSHTML 6.00.2800.1106" name=GENERATOR>
> > ><DIV><FONT face=Arial size=2><SPAN
> > >class=015465616-15092003>Hi,</SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003></SPAN></FONT>
> > ></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003>As you know
> > >there are 4 Ethernet frame formats:</SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003></SPAN></FONT>
> > ></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003>- Ethernet
> > >v2</SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN class=015465616-15092003>-
> > >802.3</SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003>- 802.3 + LLC
> > >(802.2)</SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003>- 802.3 + LLC
> > >+SNAP</SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003></SPAN></FONT>
> > ></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003></SPAN></FONT>
> > ></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003>It seems that
> > >the currently defined EFM-OAM frame format is based
> > </SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003>on Ethernet
> > >v2. What is the EFM-OAM frame format for other Ethernet
> > >frame</SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > >class=015465616-15092003>types?</SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > class=015465616-15092003></SPAN></FONT>
> > ></DIV>
> > ><DIV><FONT face=Arial size=2><SPAN
> > >class=015465616-15092003>Thanks,</SPAN></FONT></DIV>
> > ><DIV><FONT face=Arial><SPAN
> > class=015465616-15092003></SPAN></FONT><FONT
> > >face=Arial size=2><SPAN
> > class=015465616-15092003>-Shahram</SPAN></FONT></DIV>
> > ><DIV> </DIV><PRE> </PRE>
> > >
> > >
> >
> >