B.3 DNS procedures 3GPP clarifications for Dedicated Core Networks
29.3033GPPDomain Name System ProceduresRelease 17Stage 3TS
When the app-protocol as input to the S-NAPTR procedure has the substring with at least +ue included, then any app-protocol returned from DNS shall be considered to match as follows. The characters following the + character follows the ABNF grammar as follows.
"ue-" (USAGENUM)*( "." USAGENUM)
USAGENUM = 1*3(DIGIT)
DIGIT = %x30-39; 0-9
A record with any USAGENUM matching the input <usage> type value shall be considered as matching. As an example, x-s10+ue-8 as S-NAPTR input shall match a record with x-s10+ue-3.8.10.38, but shall not match a record with x-s10+ue-3.10.38.