in RFC4566 (SDP)
in RFC2326
in RFC2848
in RFC3108
in RFC3312
in RFC3407
in RFC3605
in RFC3611
in RFC3890
in RFC4145
in RFC4567
in RFC4568
in RFC4570
in RFC4574
in RFC4583
in RFC4585
in RFC4796
in RFC4975
in RFC5159
in RFC5245
in RFC5432
in RFC5506
in RFC5547
in RFC5576
in RFC5583
in RFC5760
in RFC5761
in RFC5762
in RFC5888
in RFC5939
in RFC6128
in RFC6189
in RFC6193
in RFC6230
in RFC6236
in RFC6284
in RFC6285
in RFC6364
in RFC6679
in RFC6714
in RFC6773
in RFC6787
in RFC6849
in RFC6871
in RFC6947
in RFC7006
in RFC7195
in RFC7197
in RFC7266
in RFC7272
in RFC7273
in RFC7701
in RFC7825
in RFC7826
in RFC7866
in RFC8122
in RFC8124
in RFC8285
in RFC8373
in 3GPP TS 24.229
in 3GPP TS 24.337
in 3GPP TS 26.114
in 3GPP TS 26.234
in 3GPP TS 26.346