Ethernet OAM BCPs Please are there any yet???

Adam Vitkovsky adam.vitkovsky at
Thu Sep 27 07:39:29 UTC 2012

Thank you so much Jonathon. 
This is exactly what I what I was searching for.
Oh and yes I should have mentioned I'd like to do the Y.1731 and measure the
delay and delay variance

Just yesterday evening I found a great article about how ATT did theirs
active measurements though for IP - wondering if I could do the same for my
They used dedicated servers and I'll be running this form the routers
ME3600X and CX and ASR9K so I'm a bit worried about the scaling of the whole

ATT basically used two probes and each 24-hour day is divided into 96 test
cycles of 15 minutes

A Poisson probe sequence of duration equal to the test cycle
 - Poisson distribution with average interarrival time of 3.3 s
 - Packet size of 278 bytes, including headers 
 - UDP protocol

Two periodic probe sequences in every test
 - Interval of 20 ms between successive packets (or 50 packets/s)
 - 1 min duration
 - Random start time within the 15 min cycle
 - Packet size of 60 bytes (including headers)
 - UDP protocol


-----Original Message-----
From: Jonathon Exley [mailto:Jonathon.Exley at] 
Sent: Wednesday, September 26, 2012 6:34 PM
To: nanog at
Subject: RE: Ethernet OAM BCPs Please are there any yet???

The ITU recommend the following levels:

5,6,7 = Customer
3,4  = Provider
1,2  = Operator
0    = Local segment

I don't know if there are any rules of thumb for the CCM interval - faster
is more sensitive & unstable, slow is sluggish but stable. The spec allows
between 3.33 ms and 10 minutes in 7 steps, with 1s being the midpoint. So we
use 1s intervals.

I'm not sure if the other parameters you mention are configurable for CCM. I
think the packet has a constant size. Are you wanting to also do Y.1731
performance management?


> -----Original Message-----
> From: Adam Vitkovsky [mailto:adam.vitkovsky at]
> Sent: Wednesday, 26 September 2012 9:29 p.m.
> To: nanog at
> Subject: Ethernet OAM BCPs Please are there any yet???
> Hi
> Are there any best common practices for the CFM levels use Since my 
> pure Ethernet aggregation layers are small I believe I only need two 
> CFM levels I plan on using Level 5 between CPEs managed by us and 
> Level 4 between Aggregation devices -that's where MPLS PWs kicks in So 
> leaving Level 7 and Level 6 for customers and carrier-customers 
> respectfully -would this be enough please?
> I'm also interested on what's the rule of thumb for CCMs Frequency, 
> Number of Packets, Interpacket Interval, Packet Size and Lifetime for 
> the particular operation Thanks a lot for any inputs

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