Internet Assigned Numbers Authority • Domains • Protocols • Numbers • About UDP Speed Test Protocol (UDPSTP) Created 2025-09-26 Last Updated 2026-05-08 Note Values reserved for Experimental Use are not expected to be used on the Internet but are expected to be used for experiments that are confined to closed environments. Available Formats [IMG] XML [IMG] HTML [IMG] TXT Registries Included Below • PDU Identifier • Protocol Version • Test Setup PDU Modifier Bitmap • Test Setup PDU Authentication Mode • Test Setup PDU Command Response Field • Test Activation PDU Command Request • Test Activation PDU Modifier Bitmap • Test Activation PDU Rate Adjustment Algo • Test Activation PDU Command Response Field PDU Identifier Expert(s) Ruediger Geib, Len Ciavattone, Xiao Min Reference [RFC 9946] Available Formats [IMG] CSV Range Registration Procedures 0x0000 Reserved 0x0001-0x7F00 Specification Required 0x7F01-0x7FE0 Experimental Use 0x7FE1-0x7FFF Private Use 0x8000-0xFFFE IETF Review 0xFFFF Reserved Value Description Reference Change Controller 0x0000 Reserved [RFC 9946] IETF 0x7F01-0x7FE0 Reserved for Experimental Use [RFC 9946] IETF 0x7FE1-0x7FFF Reserved for Private Use [RFC 9946] IETF 0xACE1 Test Setup PDU [RFC 9946] IETF 0xACE2 Test Activation PDU [RFC 9946] IETF 0xBEEF Load PDU [RFC 9946] IETF 0xDEAD Null PDU [RFC 9946] IETF 0xFEED Status Feedback PDU [RFC 9946] IETF 0xFFFF Reserved [RFC 9946] IETF Protocol Version Expert(s) Ruediger Geib, Len Ciavattone, Xiao Min Reference [RFC 9946] Available Formats [IMG] CSV Range Registration Procedures 0-19 Reserved 20-40960 IETF Review 40961-53248 Specification Required 53249-65534 Experimental Use 65535 Reserved Value Reference Change Controller 20 [RFC 9946] IETF Test Setup PDU Modifier Bitmap Reference [RFC 9946] Available Formats [IMG] CSV Range Registration Procedures 00000000-01111111 IETF Review 10000000 Reserved Value Description Reference 0x00 No modifications [RFC 9946] 0x01 Allow Jumbo datagram sizes above sending rates of 1 Gbps [RFC 9946] 0x02 Use Traditional MTU (1500 bytes with an IP header) [RFC 9946] Test Setup PDU Authentication Mode Reference [RFC 9946] Available Formats [IMG] CSV Range Registration Procedures 0-59 IETF Review 60-63 Experimental Use 64-255 Reserved Value Description Reference 0 Not used [RFC 9946] 1 Required authentication for the Control phase [RFC 9946] 2 Required authentication for the Control and Data phases [RFC 9946] Test Setup PDU Command Response Field Expert(s) Ruediger Geib, Len Ciavattone, Xiao Min Reference [RFC 9946] Available Formats [IMG] CSV Range Registration Procedures 0-127 IETF Review 128-239 Specification Required 240-249 Experimental Use 250-254 Private Use 255 Reserved Value Description Reference Change Controller 0 None (used by client in Request) [RFC 9946] IETF 1 Acknowledgment [RFC 9946] IETF 2 Bad protocol version [RFC 9946] IETF 3 Invalid Jumbo datagram option [RFC 9946] IETF 4 Unexpected authentication in Setup Request [RFC 9946] IETF 5 Authentication missing in Setup Request [RFC 9946] IETF 6 Invalid authentication method [RFC 9946] IETF 7 Authentication failure [RFC 9946] IETF 8 Authentication time is invalid in Setup Request [RFC 9946] IETF 9 No maximum test bit rate specified [RFC 9946] IETF 10 Server maximum bit rate exceeded [RFC 9946] IETF 11 MTU option does not match server [RFC 9946] IETF 12 Multi-connection parameters rejected by server [RFC 9946] IETF 13 Connection allocation failure on server [RFC 9946] IETF 14-239 Unassigned 240-249 Reserved for Experimental Use [RFC 9946] IETF 250-254 Reserved for Private Use [RFC 9946] IETF 255 Reserved [RFC 9946] IETF Test Activation PDU Command Request Expert(s) Ruediger Geib, Len Ciavattone, Xiao Min Reference [RFC 9946] Available Formats [IMG] CSV Range Registration Procedures 0-127 IETF Review 128-239 Specification Required 240-249 Experimental Use 250-254 Private Use 255 Reserved Value Description Reference Change Controller 0 No Request [RFC 9946] IETF 1 Request test in upstream direction (client to server) [RFC 9946] IETF 2 Request test in downstream direction (server to client) [RFC 9946] IETF 3-239 Unassigned 240-249 Reserved for Experimental Use [RFC 9946] IETF 250-254 Reserved for Private Use [RFC 9946] IETF 255 Reserved [RFC 9946] IETF Test Activation PDU Modifier Bitmap Reference [RFC 9946] Available Formats [IMG] CSV Range Registration Procedures 00000000-01111111 IETF Review 10000000 Reserved Value Description Reference 0x00 No modifications [RFC 9946] 0x01 Set when srIndexConf is start rate for search [RFC 9946] 0x02 Set for randomized UDP payload [RFC 9946] Test Activation PDU Rate Adjustment Algo Reference [RFC 9946] Note The algorithm identifier is a capitalized alphabetic UTF-8 value (A-Z), specified by the corresponding incremental numeric. Available Formats [IMG] CSV Range Registration Procedures A-Y IETF Review Z Reserved Value (Numeric) Description Reference A(n/a) Not used [RFC 9946] B(0) Rate algorithm Type B [Y.1540Amd2] C(1) Rate algorithm Type C [TR-471] Test Activation PDU Command Response Field Expert(s) Ruediger Geib, Len Ciavattone, Xiao Min Reference [RFC 9946] Available Formats [IMG] CSV Range Registration Procedures 0-127 IETF Review 128-239 Specification Required 240-249 Experimental Use 250-254 Private Use 255 Reserved Value Description Reference Change Controller 0 None (used by client in Request) [RFC 9946] IETF 1 Server acknowledgment [RFC 9946] IETF 2 Server indicates an error [RFC 9946] IETF 3-239 Unassigned 240-249 Reserved for Experimental Use [RFC 9946] IETF 250-254 Reserved for Private Use [RFC 9946] IETF 255 Reserved [RFC 9946] IETF Licensing Terms