Routing basics
Level L2
A good understanding of routing is necessary to correctly classify segments.
The WME classifies segments according to a hierarchy that directly influences the navigation algorithm, particularly for long-distance trips.
Road type hierarchy
From most important to least important:
- Freeways and expressways (Freeway / Major Highway)
- Ramps (special case)
- Major roads (Minor Highway)
- Primary streets (Primary Street)
- Streets (Street)
Continuity principle
Type continuity is essential in the WME: you must never interrupt a sequence of segments of a given type with segments of a lower type.
Example: a national road must not be interrupted by a segment classified as "Street". This breaks the consistency of the network and disrupts the calculation of long routes.
Pruning mechanism
Waze uses a system of progressive pruning: the further you move away from the origin or the destination, the more low-priority roads are excluded from the calculation.
| Road type | Behavior |
|---|---|
| Street / Primary street | Excluded beyond a certain distance threshold |
| Major / minor roads | Higher exclusion threshold |
| Freeways / Ramps | Never excluded |
Short vs long trips
Short trip (e.g. Genève to Lausanne): all road types are considered, including local streets.
Long trip (e.g. Genève to Zurich): only freeways and major roads are used. Secondary roads come into play only near the origin/destination or during a recalculation.
Routing preferences
Misconception
The "Avoid" preferences in the app do not prevent the local use of a segment. They only adjust the pruning thresholds for long-distance trips. A "penalized" segment remains usable locally.
Example
A road classified as "penalized" will always be used if it is the only option to reach a destination in the neighborhood. The effect only appears on large route calculations.
Lock levels
Swiss standard: expected lock level by road type.
| Road type | Lock level |
|---|---|
| Freeway | L5 |
| Major Highway | L4 |
| Minor Highway | L3 |
| Primary Street | L2 |
| Street | L1 |
Reminder
The higher a road type is in the hierarchy, the higher the expected lock level. This protects the structuring segments of the network against unintentional modifications.
Lock in moderation. Locking mainly targets structuring types: freeways, roads, ramps and roundabouts. You should not lock everything without reason, because an overly broad lock needlessly slows down other editors.
An editor can only modify a locked segment if their rank is at least equal to the lock level. Choose the lock level according to the importance of the segment, not out of excessive caution.
Sources
- Routing basics: segment types in WME and effects on long/short trips: https://www.waze.com/discuss/t/bases-du-routing-types-de-segments-dans-wme-et-effets-sur-les-trajets-longs-courts/389975
- Information in French: https://www.waze.com/discuss/t/informations-en-francais/377254
- Lock levels: Swiss community rules condensed in the WME Switzerland Helper script.