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Re: [EFM] OAM loop back / echo server function


I am trying to find  way to provide some lower level remote trouble 
shooting functionality.  Do you have a suggestion for an alternative that 
does not involve traffic that will go through the 802.1/802.2 level?

Thank you,
Roy Bynum

At 05:08 PM 9/4/01 -0700, Geoff Thompson wrote:
>At 06:05 PM 9/4/01 -0500, Roy Bynum wrote:
>>Would a MAC Control frame with a specific opcode  be usable as an L2 
>>ping.  This would take the frame all the way to the MAC control layer, 
>>through all of the PHY and RS.
>This function "could" be added to MAC control.
>It is not clear that there would be any special reason to do so.
>You would have to make a convincing case that there was some special 
>advantage to doing this vs. using an existing, well known protocol. 
>According to my file copy of RFC 1060 (very old version of Assigned 
>Numbers) decimal 36864 (9000 Hex) packet type is assigned to Loopback.
>It is not clear to me that restricting the path of a Loopback/Echo/Ping to 
>just the [MAC Control][MAC][RS][PHY][Medium][PHY][RS][MAC][MAC Control] 
>would be any advantage. After all, the person machine that wants to do the 
>test would have to open a communications path to the testing [MAC 
>Control/OA&M] anyway.
>>There could also be a command within the OAM functionality that would 
>>generate a special MAC Control frame that would have an opcode that would 
>>specify a test pattern in the "parameters" field of the frame.  This 
>>could potentially provide a very valuable remote trouble shooting tool 
>>for service providers.
>>Roy Bynum
>>At 03:02 PM 9/4/01 -0700, Geoff Thompson wrote:
>>>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)
>>>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"
>>>>         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?