Bonjour Conformance Test WARNING in Multicast DNS SHARED REPLY TIMING resolution

Hello and Good day!

We are conducting Bonjour Conformance Test (BCT) for Printer device.

BCT result is PASSED but with warning in Multicast DNS, specifically,

WARNING: SHARED REPLY TIMING - UNIFORM RANDOM REPLY TIME DISTRIBUTION

Other Shared Reply Timing is passed:

PASSED: MULTIPLE QUESTIONS - SHARED REPLY TIMING - UNIFORM RANDOM REPLY TIME DISTRIBUTION

Environment:

  • BCT Tool Version: 1.5.4 (15400)
  • MacOS Sequioa 15.5
  • DUT Firmware : Linux Debian 9
  • Apple mDNSResponder 1790.80.10
  • Service types: _ipps._tcp, _uscans._tcp, _ipp._tcp, _uscan._tcp
  • Router : NEC AtermWR8370N
  • Setup: 1-to-1 [Mac->Router<-DUT connection]

Based on debug.log, this is where WARNING occurs:

NOTICE 2026-03-04 10:51:06.870187+0900 _shared_reply_timing 04103: Shared reply response times: min = 26ms, max = 114ms, avg = 65.50ms WARNING 2026-03-04 10:51:06.870361+0900 _shared_reply_timing 04136: 50 percent of the replies within the correct range fell in the interval 20ms and 46ms (should be close to 25%). PASSED (SHARED REPLY TIMING)

In the same debug.log for MULTIPLE QUESTIONS - SHARED REPLY TIMING is PASSED:

NOTICE 2026-03-04 10:52:29.912334+0900 _shared_reply_timing 04103: Shared reply response times: min = 22ms, max = 112ms, avg = 78.00ms DEBUG_2 2026-03-04 10:52:29.912849+0900 recv_packet 01997: received packet (558 bytes) PASSED (MULTIPLE QUESTIONS - SHARED REPLY TIMING)

[Details] Looking at Bonjour_Conformance_Guideline.pdf https://download.developer.apple.com/Documentation/Bonjour_Conformance_Test_Guideline/Bonjour_Conformance_Guideline.pdf

there were some differences:

  1. In 1.6.2 Expected Result: Test Result File of Test that All Tests Passed, this is not displayed:

PASSED: SHARED REPLY TIMING - UNIFORM RANDOM REPLY TIME DISTRIBUTION

  1. And in II.8 Shared Reply Timing:

(Ideally, 25% of the answers should fall in each 21ms quadrant of the range 20ms - 125ms.) and comparing to the debug.log, there was a discrepancy of the interval, because 20ms and 46ms is 26ms interval.

  1. From RFC6762 6. Responding, Ideal range is from 20ms-120ms

Because of this, please advise on the questions below:

  • I would like to know on the possible cause and resolution for these WARNINGS.
  • And since in current BCT result, (Test result integrity signature is generated), I would like to know if this is acceptable for BCT certification.

Thank you.

Bonjour Conformance Test WARNING in Multicast DNS SHARED REPLY TIMING resolution
 
 
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