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RE: [EFM] OAM developing Geoff's observation.


I have given a presentation to Howard that I had intended to for 
Copenhagen.  I was looking forward to a very active question and answer 
session after presentation.   When I asked, Howard was busy with some very 
critical issues and had not had time to put the presentations on the Web 
site.  When he does, then you will be able to see two methods that would 
add the OAM as an "out-of-band" function and use the existing GbE PCS.  It 
would borrow heavily from existing technology and not add any complexity or 
require any new functionality in the existing GbE PCS or higher sublayers.

Thank you,
Roy Bynum

At 11:40 AM 9/15/01 -0700, Sanjeev Mahalawat wrote:

>Hi Bob,
>I think following issues for OAM in EFM to decide in-band or side-band OAM 
>1. What needs to be done for OAM in 802.3ah? Influences in-band or 
>side-band decision?
>2. How OAM is done?
>Since, 802.3ah has extension EFM (etherenet in first mile), with that 
>there seems to be two choices:
>    a) Both layer 1 and layer 2 are Ethernet, or
>    b) layer 1 does not have to be Ethernet, but layer 2 is Ethernet.
>In case a) there are further couple of choices:
>i)  All the existing Ethernet PHYs and any new 802.3 PHY MUST be supported.
>ii) A new EFM phy will be developed and MUST be supported, and support for 
>     802.3 Ethernet PHY is optional.
>If only a) and ii) are the objectives then either in-band or side-band can 
>achieve the
>objective with side-band (preamble/ipg) being more beneficial. If b) and 
>i) are objectives
>then I am not sure there are many choices other than in-band.
>Now, if EFM Service Providers want side-band (preamble/ipg or any other 
>added SONET/SDH like)
>solution (and hence a requirement) then objectives can be accordingly, 
>i.e. a) and ii) from above.
>But, if the method is not specified and left to open then I guess 
>everybody is open to non-interoperability.
>Sanjeev Mahalawat
>At 01:36 PM 09/15/2001 +0100, Bob Barrett wrote:
> >
> >I'm late in on this thread, so there may be a similar comment further up my
> >in-box from somebody else.
> >
> >Geoff's observation is pretty fundamental:
> >
> >> My expectation is that the demarcation device will probably end
> >> up with an IP address in order to support:
> >>          SNMP for OA&M
> >>          Firewall services for the subscriber
> >>
> >> (That issue is, of course, beyond our scope)
> >
> >The logical conclusion of this observation is that EFM should make the OAM
> >at layer two as simplistic as possible fulfilling only the basic
> >requirements i.e. limited number of managed objects and limited echo (L2
> >ping) test. Vendors can then leverage ietf standards (note: the users tends
> >to like these) to implement ietf style 'standard' management functions.
> >Isn't that what we all have in mind anyway :-).
> >
> >The open question then is will the service provider market accept in-band
> >management i.e. management IP frames mixed with user traffic, or is there a
> >real requirement for a side-band channel. If EFM does need to include a side
> >band channel then all that it needs to be is a communications channel (bit
> >stream), probably squeezed in the preamble or the IPG (we can debate that
> >choice for a while). Vendors can then implement either a standards based
> >method of comms over that channel or do there own thing. Personally I would
> >expect vendors to choose something like IP over PPP for this.
> >
> >I can wrap this all up in a presentation for the next meeting if required.
> >
> >(Just seen Geoff's comment on this in response to Roy's thread; as a vendor
> >we will probably want to support both in-band and side-band, standardised or
> >not, but we would prefer a standard for side band as part of EFM).
> >
> >Bob Barrett
> >
> >> -----Original Message-----
> >> From:
> >> []On Behalf Of Geoff
> >> Thompson
> >> Sent: 04 September 2001 23:03
> >> To: fkittred@xxxxxxx
> >> Cc:
> >> Subject: Re: [EFM] OAM loop back / echo server function
> >>
> >>
> >>
> >> Fletcher-
> >>
> >> I don't think this is a stupid question.
> >> I don't think we need an IP level PING
> >> A L2 ping would do, perhaps even better, the demarc would look for PING
> >> type and then just swap SA & DA.
> >> My expectation is that the demarcation device will need a MAC address
> >> My expectation is that the demarcation device will probably end
> >> up with an
> >> IP address in order to support:
> >>          SNMP for OA&M
> >>          Firewall services for the subscriber
> >>
> >> (That issue is, of course, beyond our scope)
> >>
> >> Geoff
> >>
> >> At 03:47 PM 9/4/01 -0400, Fletcher E Kittredge wrote:
> >> >On Fri, 31 Aug 2001 14:11:54 -0700  "Geoff Thompson" wrote:
> >> > > As I have said before, I do believe that we will need a
> >> demarcation device
> >> > > that has the capability to host OA&M functions.
> >> > > We have talked about "loop back" from this point in the network.
> >> > > Let us forevermore make that "PING"
> >> >
> >> >Geoff;
> >> >
> >> >         Apologies if this is a stupid question, but does PING in this
> >> >context mean the utility that sends an IP ICMP ECHO REQUEST packet and
> >> >listens for an ECHO REPLY packet?  If so, am I correct in thinking this
> >> >means the demarcation device would require an IP address?
> >> >
> >> >thanks!
> >> >fletcher
> >>
> >