IP SLA - one-way delay

[ChrisNewnham_]

For those SLA probes that support one-way delay statistics, e.g. UDP Jitter, does the one-way delay measurement always require a Cisco endpoint using ip sla responder feature?

Thanks!

[Joseph W. Doherty]

Hmm, unsure jitter is truly a one way measurement, although it's easy to think it is.

As far as requiring a SLA responder to measure jitter, unsure that's true too.  The biggest feature of a SLA responder is it tells the sender how long it took to respond, so that time is NOT attributed to the network.

Anyway, for measuring jitter in just one direction, I can see it being done with packets carrying additional information, which possibly many applications don't provide.  If they don't, a sender could figure jitter for the round trip, independent of packet contents, but it wouldn't be able to truly tell either direction's jitter or receiver's impact to measurements.

[MHM Cisco World]

-For udp jitter you need responders 

-For icmp jitter the responder is optional' but it recommends to config it.

MHM

[ChrisNewnham_]

That didn't actually answer my question  

I know that UDP Jitter requires responders, my question does the one-way delay measurement require a Cisco responder (UDP Jitter itself does not itself require a Cisco responder).

[MHM Cisco World]

Yes friend  I answer you 

Udp jitter (one way or other) need responders.

MHM

[ChrisNewnham_]

Can you please specify if you mean a Cisco responder, or a standard IP/application device that is listening on UDP Port 7  

UDP Jitter for VOIP requires a Cisco responder

UDP Jitter requires any responder (Cisco or not) ---> this is the one I am talking about

[MHM Cisco World]

Wait I think I found something help you' let me check it in lab'

Udp use control to make responder know the udp port it use.

There is a note that this control if disable ypu dont need responder.

But let me check it

MHM

[MHM Cisco World]

control is disable and the responder is not config 

[MHM Cisco World]

the control is disable and the responder is only config with ipaddress and port (no ip sla responder)
it work 
so you need either

1-enable control and config ip sla responder 
or
2-disable control (in sender) and config 
#ip sla responder udp-echo ipaddress 100.0.0.2 port 1000

MHM

[ChrisNewnham_]

Thanks MHM, but just to bring it back to the original question

For the UDP Jitter SLA, can a non-Cisco responder (which are supported for this SLA) be used to provide one-way delay statistics?

[MHM Cisco World]

For the UDP Jitter SLA, can a non-Cisco responder (which are supported for this SLA)? It support what can you elaborate.

Thanks 

MHM

[ChrisNewnham_]

One-way delay statistics.

Thanks

[MHM Cisco World]

if it non-cisco how is support IP SLA UDP jitter, non-cisco not support to be sender or responder.
and if you use cisco then you need as I mention above. 

MHM

[ChrisNewnham_]

So what that says is, "you cannot configure an IP SLA responder on a non-Cisco device".

It does not say, you can't use a non-Cisco device as a responder for this probe.

This document says UDP Jitter for VOIP requires Cisco Endpoints, but UDP Jitter does not.

https://www.cisco.com/en/US/technologies/tk648/tk362/tk920/technologies_qas0900aecd8017bd5a.html

Where did that screenshot come from, a book perhaps? It doesn't even mention UDP Jitter for VOIP only UDP Jitter, so I wonder if it is quite old.

[MHM Cisco World]

Friend 

I dont have much to say after all above.

Udp jitter need udp port which work with control enable or disable' and both need cisco device to config.

Thanks 

Have  a nice day 

MHM