Routing Protocol for Low Power and Lossy Networks (RPL) Routing Metric/Constraint 2012-03-28 Routing Metric/Constraint Type IETF Review 0 Unassigned 1 Node State and Attribute 2 Node Energy 3 Hop Count 4 Link Throughput 5 Link Latency 6 Link Quality Level 7 Link ETX 8 Link Color 9-255 Unassigned Routing Metric/Constraint TLVs First Come First Served 0-255 Unassigned Routing Metric/Constraint Common Header Flag field IETF Review 8 Recorded/Aggregated 7 Optional Constraint 6 Constraint/Metric 5 P (Partial) 0-4 Reserved Routing Metric/Constraint Common Header A field IETF Review 0 Routing metric is additive 1 Routing metric reports a maximum 2 Routing metric reports a minimum 3 Routing metric is multiplicative 4-7 Unassigned NSA Object Flag field IETF Review 0-5 Reserved 6 Aggregator 7 Overloaded Hop-Count Object Flag field IETF Review Node Type Field IETF Review 0 a mains-powered node 1 a battery-powered node 2 a node powered by an energy scavenger 3 Unassigned