RE: [EFM] EFM-OAM frame fomat
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>
> >
> >
>
>