Diffserv / DSCP Settings

[scott.j.hanson]

For the C-series codecs, there are four items in the configuration that can have separate DiffServ values set: Video, Voice, Signaling, and Data. I think I understand the first three, but I'm unclear on "Data." Is that a reference to HTTP/HTTPS/SSH traffic (e.g. software updates, communication with TMS, admin logins)? Is there anything else I'm missing? I assume it does NOT refer to the "data" sent over the presentation channel, which would be included under the "Video" value.

[Saurabh Gupta]

Hi Scott,

Network [1..1] QoS Diffserv Data

The Diffserv Data defines which priority Data packets should have in an IP network. Enter a priority,

which ranges from 0 to 63 for the packets. The higher the number, the higher the priority. These priorities

might be overridden when packets are leaving the network controlled by the local network administrator.

NOTE: Requires the Network QoS Mode to be set to Diffserv.

Requires user role: ADMIN

Value space: <0..63>

Data: A recommended value is Diffserv Code Point (DSCP) AF23, which equals the value 22. If in

doubt, contact your network administrator.

Range: Select a value from 0 to 63.

Example: xConfiguration Network 1 QoS Diffserv Data: 0

Hope it helps.

Thanks,

Saurabh

[asafayan]

Saurabh,

He is asking specifically "what" traffic does the diffserv settings for Data pertain to.  Not just a definition of the concept.

I looked around Scott and was unable to identify what one would identify as "data".  I'm in TP training at RTP next week - I'll see if I can get an answer.

Regards,

Amir

[scott.j.hanson]

Thanks Amir, you are correct. Please let me know what you find out. I had already read the administrator's manual as quoted by Saurabh above, but it doesn't answer the question I asked.

[Yusuke Yoshinaga]

Hi Scott,

"QoS Diffserv Data" is for the packets for communicating with TMS/users; http/https, ssh, etc.

i.e., except following packets.

- Audio: audio RTP packet

- Video: video(main and contents) RTP packet

- Signalling: SIP and H.323

- ICMPv6

- NTP

Regards,

Yusuke

[Stephanie Knoop]

Yusuke,
4 years later your answer is still helpful. Thank you. I am finding that this setting for diffserv data is set to 0,24,26, and 32 on various endpoints in my environment. I assume that this is mostly user error, but also found this post that indicates that CUCM at one point in time may have the data dscp as well: https://supportforums.cisco.com/t5/telepresence/ex90-sx20-qos-and-cucm-question/td-p/2185968.

I am surprised this is not more well documented in admin guides, as it seems that plenty have assumed "data" may have been part of the presentation sharing. As a Cisco employee, I assume you are in the video space so can be trusted :), but is this documented officially anywhere?

Thank you, Stephanie