We don't currently have telemetry for our HTTP3 + ECH usage and success rate.

This patch adds telemetry which records when H3 connections succeed / fail
and what kind of ECH they used. Our H3 ECH tests are extended to test these
different modes and that the telemetry is recorded correctly.

Comment on attachment 9323540 [details]
Bug 1822876: Add H3 ECH Telemetry. r=kershaw!

Request for data collection review form

1. What questions will you answer with this data?

Is ECH+H3 working effectively for Firefox users? What is the success rate of these connections?

2. Why does Mozilla need to answer these questions? Are there benefits for users? Do we need this information to address product or business requirements? Some example responses:

These questions help us establish whether we interoperate with other implementations correctly and whether we see any blocking by network middleboxes.

3. What alternative methods did you consider to answer these questions? Why were they not sufficient?

There are no suitable alternative methods.

4. Can current instrumentation answer these questions?

No.

5. List all proposed measurements and indicate the category of data collection for each measurement, using the Firefox data collection categories found on the Mozilla wiki.

We split H3 connections into three buckets according to whether they use ECH, use GREASE'd ECH or don't use ECH at all. For each connection we record a single bit for whether it succeeded or failed. This is category 1 data.

6. Please provide a link to the documentation for this data collection which describes the ultimate data set in a public, complete, and accurate way.

This collection is documented in its definitions files Histograms.json, Scalars.yaml, and/or Events.yaml and in the Probe Dictionary at https://probes.telemetry.mozilla.org.

7. How long will this data be collected? Choose one of the following:

I (djackson) want to permanently monitor this data.

8. What populations will you measure?

All.

9. If this data collection is default on, what is the opt-out mechanism for users?

The existing Firefox opt-out preference.

10. Please provide a general description of how you will analyze this data.

Across our population of users, I will check how success rates between the three modes differ and ensure an even baseline.

11. Where do you intend to share the results of your analysis?

Likely in Firefox communications such as our security blog.

12. Is there a third-party tool (i.e. not Glean or Telemetry) that you are proposing to use for this data collection?

No.

In the future, please attach the data collection review request as a text attachment. This works out better with Data Steward workflows.

Comment on attachment 9324034 [details]
data collection review request

DATA COLLECTION REVIEW RESPONSE:

Is there or will there be documentation that describes the schema for the ultimate data set available publicly, complete and accurate?

Yes.

Is there a control mechanism that allows the user to turn the data collection on and off?

Yes. This collection can be controlled through Firefox's Preferences.

If the request is for permanent data collection, is there someone who will monitor the data over time?

Yes, :djackson is responsible.

Using the category system of data types on the Mozilla wiki, what collection type of data do the requested measurements fall under?

Category 1, Technical.

Is the data collection request for default-on or default-off?

Default on for all channels.

Does the instrumentation include the addition of any new identifiers?

No.

Is the data collection covered by the existing Firefox privacy notice?

Yes.

Does the data collection use a third-party collection tool?

No.

Result: datareview+

https://hg.mozilla.org/mozilla-central/rev/dee1eb330852