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RE: [EFM] RE: OAM functionals




Tony,

Read again what I said.  I said that it was an old way doing isolation of 
broadcast domains.  This was before there were VLANs.

Also, the information that I gave concerning the difference between a 
switch and a hub was given to me by the chair of 802.3.  He is also the 
person that was responsible for the current repeater standards in 802.3.

Thank you,
Roy Bynum

At 11:34 AM 9/27/01 +0100, Tony Jeffree wrote:
>Roy -
>
>Again, a touch of research into 802 standards and terminology might help 
>you to understand that the SNAP is nothing to do with isolating 
>management/user broadcast domains.  See chapter 10 of the 2001 rev of IEEE 
>Standard 802, which is significantly entitled: "Protocol discrimination 
>above the MAC sublayer: Subnetwork Access Protocol (SNAP) and Ethernet 
>types". No doubt the title will give you a better clue as to what SNAP is 
>really about (please note the use of the present tense here also).
>
>Regards,
>Tony
>
>
>At 17:58 26/09/2001 -0500, Roy Bynum wrote:
>
>>Harry,
>>
>>As a side note, ha, ha, ever hear of Sub Network Access Protocol.  It was 
>>an extension of the LLC type 1/2 header.  It was a very old way of 
>>isolating the management broadcast domain from the user broadcast domains. ;-)
>>
>>Roy
>>
>>At 03:34 PM 9/26/01 -0700, Harry Hvostov wrote:
>>>Faye,
>>>
>>>I think you are confusing where the the various communication
>>>mechanisms/protocols fit into the network management. Here is a brief
>>>exposition:
>>>
>>>1. Most modern EMS are distributed applications that use CORBA as the
>>>application communication mechanism for client/server communication. EMS's
>>>written in Java only could use RMI (remote method invocation) and/or EJB
>>>(enterprise Java Beans) mechanisms instead.
>>>
>>>2. SNMP is an application protocol that EMS components use to talk to
>>>network elements with SNMP agents. An EMS server may have a communication
>>>layer encapsulating SNMP protocol.
>>>
>>>3. UDP packets are transport layer (Layer 4) PDUs. So the proper
>>>encapsulation for SNMP messages on TCP/IP networks (note that SNMP is UDP/IP
>>>application protocol) is:
>>>
>>>SNMP ->UDP->IP->datalink protocol framing -> PHY
>>>
>>>What I have stated is that,  since EFM = Ethernet, the natural choice of
>>>datalink protocol encapsulation for management messages is Ethernet frames.
>>>I have never seen SNMP messages (application layer!) directly encapsulated
>>>into LLC frames, but that could be an option.
>>>
>>>4. Application of QoS mechanisms such as DiffServ DSPC marking is
>>>straightforward.
>>>
>>>5. Most commercial EMS systems have sufficient application layer
>>>intelligence to throttle management traffic during network element system
>>>startup. This does not impact CPE equipment costs - aside from the normal
>>>SNMP agent support.
>>>
>>>Harry
>>>
>>>-----Original Message-----
>>>From: Faye Ly [mailto:faye@xxxxxxxxxx]
>>>Sent: Wednesday, September 26, 2001 1:18 PM
>>>To: Harry Hvostov; bob.barrett@xxxxxxxxxxxxxxx; Romascanu, Dan (Dan);
>>>Roy Bynum; ah_smith@xxxxxxxxxxx
>>>Cc: stds-802-3-efm
>>>Subject: RE: [EFM] RE: OAM functionals
>>>
>>>
>>>Harry,
>>>
>>>Regarding 1, OSS may or may not communicate directly with
>>>OLT via CORBA/TL1/SNMP.  A lot of time it is through the
>>>EMS. (Element Manager System).  The whole discussion on
>>>this subject, I believe, is out of scope for this working
>>>group.  (I don't mind private email discussion though ...)
>>>
>>>Regarding 2, Yes, you are right, SNMP can be used for
>>>management of the CPE's.  SNMP/UDP/IP encapsulated in
>>>Ether frames is one and SNMP directly over something such
>>>as LLC is another possibility.  This does require SNMP
>>>agent plus full IP stack supports on each CPE.  SNMP also
>>>doesn't provide any mechanism to throttle the management
>>>traffic in case of 1) system startup 2) network operator
>>>error 3) mal designed NMS/OSS/EMS and so on.  Diffserv
>>>might be used to ensure QOS based on SNMP port, but this
>>>requires even more sophisicated software on CPE.  I think
>>>we are trying to maintain the cost of the CPE low.
>>>
>>>Your thoughts?
>>>
>>>-faye
>>>
>>>-----Original Message-----
>>>From: Harry Hvostov [mailto:HHvostov@xxxxxxxxxxxx]
>>>Sent: Wednesday, September 26, 2001 11:57 AM
>>>To: Faye Ly; bob.barrett@xxxxxxxxxxxxxxx; Romascanu, Dan (Dan); Roy
>>>Bynum; ah_smith@xxxxxxxxxxx
>>>Cc: stds-802-3-efm
>>>Subject: RE: [EFM] RE: OAM functionals
>>>
>>>
>>>Gents,
>>>
>>>1. SP's use OSS systems such as available from Portal S/W, Micromuse and
>>>others. These are typically distributed applications based on CORBA or
>>>similar
>>>distributed protocols. All this is resolved at the application layer.
>>>
>>>2. SNMP is again an application protocol. Hence transport of SNMP
>>>messages
>>>can be done as payload of Ethernet frames - in band. That is the method
>>>of
>>>choice today for cable access.
>>>
>>>Harry
>>>
>>>-----Original Message-----
>>>From: Faye Ly [mailto:faye@xxxxxxxxxx]
>>>Sent: Wednesday, September 26, 2001 10:58 AM
>>>To: bob.barrett@xxxxxxxxxxxxxxx; Romascanu, Dan (Dan); Roy Bynum;
>>>ah_smith@xxxxxxxxxxx
>>>Cc: stds-802-3-efm
>>>Subject: RE: [EFM] RE: OAM functionals
>>>
>>>
>>>
>>>Bob,
>>>
>>>It seems like we are coming into a conclusion that:
>>>An OAM mechanism is required to remotely manage the
>>>CPEs.  This mechanism is dedicated for OAM to ensure
>>>centralized management model (That is, from EMS to OLT
>>>and thus OLT to all CPE's.  We are only interested in
>>>the segment between OLT and CPE's).  The most important
>>>reason for needing a centralized management model is
>>>to "avoid truck roll".  The network operator from a
>>>centralized NOC should be able to remotely manage the
>>>OLT and CPE's.
>>>
>>>If I interpreted your email correctly. You are suggesting
>>>that as long as we have a mechanism, whatever OAM traffic
>>>that is transported over the mechanism is up to the vendors?
>>>I think the danger of this is that we might be taking away
>>>SP's choices on OLT and CPE vendors.  But if we say that
>>>whatever OAM traffic that is transported over the mechanism
>>>is out of scope of 802.3ah, I totally agree.
>>>
>>>-faye
>>>
>>>-----Original Message-----
>>>From: Bob Barrett [mailto:bob.barrett@xxxxxxxxxxxxxxx]
>>>Sent: Wednesday, September 26, 2001 10:19 AM
>>>To: Romascanu, Dan (Dan); Roy Bynum; Faye Ly; ah_smith@xxxxxxxxxxx
>>>Cc: stds-802-3-efm
>>>Subject: RE: [EFM] RE: OAM functionals
>>>
>>>
>>>A lot of the detailed management functions are product and vendor
>>>specific.
>>>
>>>The EFM standard should cater only for the basic management functions
>>>for
>>>test and possibly port enable/disable, but some would argue that one is
>>>product specific and a step too far.
>>>
>>>The EFM standard should provide the vendor with a channel down which to
>>>run
>>>their own management application in whatever protocol they choose be it
>>>UDP
>>>with SNMP or something proprietary. The vendors that talk to their
>>>customers
>>>(and some vendors even listen to the replies) will probably do better
>>>than
>>>those that don't :-).
>>>
>>>Bob Barrett
>>>
>>> > -----Original Message-----
>>> > From: owner-stds-802-3-efm@majordomo.ieee.org
>>> > [mailto:owner-stds-802-3-efm@majordomo.ieee.org]On Behalf Of
>>>Romascanu,
>>> > Dan (Dan)
>>> > Sent: 26 September 2001 11:48
>>> > To: Roy Bynum; Faye Ly; ah_smith@xxxxxxxxxxx
>>> > Cc: stds-802-3-efm
>>> > Subject: RE: [EFM] RE: OAM functionals
>>> >
>>> >
>>> >
>>> > Roy,
>>> >
>>> > I am trying to make a slightly different point, or ask a different
>>> > question. I am actually with you on the issue of insertion of control
>>> > plane messages in the traffic stream, but...
>>> > >
>>> > > To a certain extent, you are right.  In some ways you are wrong.
>>> > >
>>> > > Upper layer applications can provide a very rich texture of
>>> > > management and
>>> > > provisioning messaging.  The question would be whether this
>>> > > messaging would
>>> > > require insertion into the customer revenue traffic stream.
>>> > > This works for
>>> > > low margin services such as the Internet. It does not work
>>> > > for high margin
>>> > > services such as "Private Line".
>>> > >
>>> > > There are a lot of vendors that are trying to redefine
>>> > > "Private Line".  The
>>> > > sad truth is that it is the customer of the service providers
>>> > > that define
>>> > > what "Private Line" is.  At present, and in the foreseeable future,
>>> > > "Private Line" is a private, secure, fixed bandwidth
>>> > > facility, that is not
>>> > > shared with other "customers".  "Private Line" has the
>>> > > service provider
>>> > > management out side of the customer's revenue traffic.
>>> > >
>>> > >
>>> >
>>> > Note that you did not use the word Ethernet even once!
>>> >
>>> > My point is that the chassis management issues need to be part of a
>>> > layer of management that is not Ethernet (or other data layer)
>>>specific.
>>> > What needs to be defined is the information model for a control plane
>>> > (which is not lower layer specific) and than mappings to the specific
>>> > layers. I sympathize with the need and I understand the requirement,
>>>but
>>> > I am not sure that the first part is within our charter. Maybe there
>>>are
>>> > other standard groups dealing with this. I am not sure that this group
>>> > is well prepared to deal with chassis management or facilities alarms,
>>> > and I am wondering if you as a service provider would not prefer one
>>> > single interface to present such information, for all the data layer
>>> > technologies that run the services that you sell.
>>> >
>>> > It might be that
>>> > Regards,
>>> >
>>> > Dan