ghs-demo-edgemetrics.cpp File Reference

#include "ghs-demo-edgemetrics.h"
#include <algorithm>

Functions
CommsEdgeMetric	sym_metric (const uint16_t agent_to, const uint16_t agent_from, const Kbps kbps)
	Dark magic to provide a symmetric, unique link-metric based on throughput and the two agent ids More...

Detailed Description

Copyright

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Function Documentation

sym_metric()

CommsEdgeMetric sym_metric	(	const uint16_t	agent_id,
		const uint16_t	agent_from,
		const Kbps	kbps
	)

Dark magic to provide a symmetric, unique link-metric based on throughput and the two agent ids

Required for proper execution of le::ghs::GhsState. The 64bit return value is composed of 32 bits of throguhput left-shifted by 32 bits, OR-masked with the larger agent id left shifted 16 bits, finally OR-masked with the lower agent id.

The resulting "hashy-metric" is:

• Unique, in that even with identical throughputs, no two pairs of agents will have identical comms metrics
• Symmetrical, in that both agents, if they agree on throughput can agree on the metric to use
• Dominated by throughput, so no two agent ids are somehow more important than raw transmission power

See also

le::ghs::metric_t

le::ghs::GhsState

demo::Comms::little_iperf()