sctp_parameters.go

package mediasoup

type SctpCapabilities struct {
	NumStreams NumSctpStreams `json:"numStreams"`
}

// NumSctpStreams defines the SCTP streams configuration.
//
// Both OS and MIS are part of the SCTP INIT+ACK handshake. OS refers to the
// initial int of outgoing SCTP streams that the server side transport creates
// (to be used by DataConsumers), while MIS refers to the maximum int of
// incoming SCTP streams that the server side transport can receive (to be used
// by DataProducers). So, if the server side transport will just be used to
// create data producers (but no data consumers), OS can be low (~1). However,
// if data consumers are desired on the server side transport, OS must have a
// proper value and such a proper value depends on whether the remote endpoint
// supports  SCTP_ADD_STREAMS extension or not.
//
// libwebrtc (Chrome, Safari, etc) does not enable SCTP_ADD_STREAMS so, if data
// consumers are required,  OS should be 1024 (the maximum int of DataChannels
// that libwebrtc enables).
//
// Firefox does enable SCTP_ADD_STREAMS so, if data consumers are required, OS
// can be lower (16 for instance). The mediasoup transport will allocate and
// announce more outgoing SCTM streams when needed.
//
// mediasoup-client provides specific per browser/version OS and MIS values via
// the device.sctpCapabilities getter.
type NumSctpStreams struct {
	// OS defines initially requested int of outgoing SCTP streams.
	OS uint16 `json:"OS"`

	// MIS defines maximum int of incoming SCTP streams.
	MIS uint16 `json:"MIS"`
}

type SctpParameters struct {
	// Port must always equal 5000.
	Port uint16 `json:"port"`

	// OS defines initially requested int of outgoing SCTP streams.
	OS uint16 `json:"os"`

	// MIS defines maximum int of incoming SCTP streams.
	MIS uint16 `json:"mis"`

	// MaxMessageSize defines maximum allowed size for SCTP messages.
	MaxMessageSize uint32 `json:"maxMessageSize"`

	// Set by worker.
	IsDataChannel      bool `json:"isDataChannel,omitempty"`
	SctpBufferedAmount int  `json:"sctpBufferedAmount,omitempty"`
	SendBufferSize     int  `json:"sendBufferSize,omitempty"`
}

// SctpStreamParameters describe the reliability of a certain SCTP stream.
// If ordered is true then maxPacketLifeTime and maxRetransmits must be false.
// If ordered if false, only one of maxPacketLifeTime or maxRetransmits can be true.
type SctpStreamParameters struct {
	// StreamId defines SCTP stream id.
	StreamId uint16 `json:"streamId"`

	// Ordered defines whether data messages must be received in order. If true the messages will
	// be sent reliably. Default true.
	Ordered *bool `json:"ordered,omitempty"`

	// MaxPacketLifeTime defines when ordered is false indicates the time (in milliseconds) after
	// which a SCTP packet will stop being retransmitted.
	MaxPacketLifeTime uint16 `json:"maxPacketLifeTime,omitempty"`

	// MaxRetransmits defines when ordered is false indicates the maximum number of times a packet
	// will be retransmitted.
	MaxRetransmits uint16 `json:"maxRetransmits,omitempty"`
}