coordinate

type Client struct {
	// contains filtered or unexported fields
}

type ClientStats struct {
	// Resets is incremented any time we reset our local coordinate because
	// our calculations have resulted in an invalid state.
	Resets int
}

type Config struct {
	// The dimensionality of the coordinate system. As discussed in [2], more
	// dimensions improves the accuracy of the estimates up to a point. Per [2]
	// we chose 8 dimensions plus a non-Euclidean height.
	Dimensionality uint

	// VivaldiErrorMax is the default error value when a node hasn't yet made
	// any observations. It also serves as an upper limit on the error value in
	// case observations cause the error value to increase without bound.
	VivaldiErrorMax float64

	// VivaldiCE is a tuning factor that controls the maximum impact an
	// observation can have on a node's confidence. See [1] for more details.
	VivaldiCE float64

	// VivaldiCC is a tuning factor that controls the maximum impact an
	// observation can have on a node's coordinate. See [1] for more details.
	VivaldiCC float64

	// AdjustmentWindowSize is a tuning factor that determines how many samples
	// we retain to calculate the adjustment factor as discussed in [3]. Setting
	// this to zero disables this feature.
	AdjustmentWindowSize uint

	// HeightMin is the minimum value of the height parameter. Since this
	// always must be positive, it will introduce a small amount error, so
	// the chosen value should be relatively small compared to "normal"
	// coordinates.
	HeightMin float64

	// LatencyFilterSamples is the maximum number of samples that are retained
	// per node, in order to compute a median. The intent is to ride out blips
	// but still keep the delay low, since our time to probe any given node is
	// pretty infrequent. See [2] for more details.
	LatencyFilterSize uint

	// GravityRho is a tuning factor that sets how much gravity has an effect
	// to try to re-center coordinates. See [2] for more details.
	GravityRho float64

	// metricLabels is the slice of labels to put on all emitted metrics
	MetricLabels []metrics.Label
}

type Coordinate struct {
	// Vec is the Euclidean portion of the coordinate. This is used along
	// with the other fields to provide an overall distance estimate. The
	// units here are seconds.
	Vec []float64

	// Err reflects the confidence in the given coordinate and is updated
	// dynamically by the Vivaldi Client. This is dimensionless.
	Error float64

	// Adjustment is a distance offset computed based on a calculation over
	// observations from all other nodes over a fixed window and is updated
	// dynamically by the Vivaldi Client. The units here are seconds.
	Adjustment float64

	// Height is a distance offset that accounts for non-Euclidean effects
	// which model the access links from nodes to the core Internet. The access
	// links are usually set by bandwidth and congestion, and the core links
	// usually follow distance based on geography.
	Height float64
}

type DimensionalityConflictError struct{}

type Stats struct {
	ErrorMax float64
	ErrorAvg float64
}