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0x08

TRANSPORT_PARAMETER_ERROR

RFC 9000 §20

QUIC TRANSPORT_PARAMETER_ERROR (0x08) is sent when a QUIC transport parameter is invalid, duplicated, or forbidden in a particular context. Transport parameters are negotiated in the TLS handshake. Receiving an invalid parameter set terminates the connection before data can flow.

Code

0x08

Decimal

8

Standard

RFC 9000 §20

Description

QUIC transport parameters are carried in TLS extension data during the handshake (RFC 9001). Each parameter has specific validity rules: some are only legal for the server to send, some have minimum/maximum value constraints, and no parameter may appear more than once. Examples of violations: the client sending original_destination_connection_id (which only the server may send), a parameter with a value exceeding its defined maximum, a required parameter omitted, or the same parameter ID appearing twice. Any of these causes TRANSPORT_PARAMETER_ERROR. This error occurs during the handshake phase, so it terminates the connection before any application data is exchanged. It indicates a bug in the QUIC implementation's parameter generation or validation logic.

Common Causes

  • Client sent a server-only transport parameter
  • Transport parameter value outside its allowed range
  • Same transport parameter ID appears more than once
  • Required transport parameter omitted
  • QUIC implementation bug in transport parameter encoding