Glossary

One sentence per term, grouped by topic. Search finds every term by its name.

The network

Node

A place in the network with a measured position and height: a handhole, manhole, cabinet, splice closure, pole, or a single surveyed point such as a bend.

Handhole

A small underground chamber where cables can be pulled, spliced or stored; in ruumica a type of node.

Span

The physical route between two nodes, such as a trench or a duct, with its course of points and its length.

Split

Adding a node in the middle of a span: the span is retired, and two new spans take its place.

Cable

A cable with a number of fibres that runs through one or more spans along its route.

Route

The ordered list of spans a cable runs through, each in or against the span’s direction.

Fibre

One glass fibre in a cable, named by its tube colour, fibre colour and number.

Splice

The joint of one fibre of one cable to one fibre of another, in a closure at a node.

Slack loop

Spare cable stored at a node, such as a coil in a vault; it counts toward the fibre’s length.

Evidence

A photo, video or sketch of a node or span, kept unchanged and named by its fingerprint.

Heights and coordinates

Elevation

A height above the national reference surface in the project’s height system; never a depth.

Height system

The national reference for elevations, such as EH2000 in Estonia or NN2000 in Norway.

Ellipsoidal height

The height a GNSS receiver measures, above a smooth mathematical shape of the earth; it differs from an elevation by many metres.

Geoid model

A grid of the difference between ellipsoidal heights and elevations, published by the national mapping authority, such as EST-GEOID2017.

L-EST97

The Estonian national map coordinate system (EPSG:3301).

Pipeline

One fixed, verified recipe for converting GNSS coordinates into a project’s delivery coordinates; it is never changed in place.

Grid

A data file a pipeline needs, such as a geoid model, identified by its SHA-256 fingerprint.

Control point

A national reference point the survey is tied to, with official coordinates.

Depth

A distance measured downward from the ground surface, such as the cover over a duct.

OTDR measurements

OTDR

An optical time-domain reflectometer: an instrument that sends light into a fibre and records what returns along its length.

Event

A point along a fibre where the OTDR sees a loss or a reflection, such as a splice, a connector or the fibre end.

Group index

The value (IOR) an OTDR uses to turn the time of travel of light into distance; a wrong value shifts every distance.

Pair

Two measurements of the same fibre, one from each end, at the same wavelength, judged together.

Length factor

How much longer a cable’s fibres are than its route, because they lie in a helix with some excess length.

Reflectance

How much light an event sends back, in dB; the more negative, the better.

Verdict

The judgement of a trace: PASS, FAIL, or PROVISIONAL while only one direction is measured.

Deliveries

Freeze instant

The moment whose state of the project a delivery contains, given in UTC with --frozen-at.

Frozen package

Every fact a delivery is made from, as of the freeze instant, in one document (package.json).

Closeout package

The folder and ZIP an export writes: drawing, data files, closeout book, raw evidence and manifest.

Closeout book

The PDF in a closeout package, written for the person who accepts the delivery.

Manifest

The file manifest.json, which lists every file of a closeout package with its fingerprint.

Fingerprint

The SHA-256 of a file: 64 characters that change completely if one byte of the file changes.

Export profile

The file that decides layers, symbols, title block and sheet for one authority; provisional or production.

Bill of quantities

The built lengths and counts of a project, as of a freeze instant, in whole millimetres and pieces.

Quality level

How reliably a position is known, from QL-A, the most reliable, to QL-D; assessing it is not built yet.

Offline work

Op

One change made in the field, such as a new node or a splice, sent to the server as a self-contained record.

Starting point

The project as it was when offline sync was turned on, from which every replay begins.

Replay

Recomputing a project from its starting point with every op in the agreed order, when an op arrives late.

Hold

The server keeping an op from taking effect until a reason is resolved, such as a missing height.

Conflict

Two changes that contradict each other; the later one has no effect until the office decides.

Edge

The part of ruumica that runs at Cloudflare and receives ops and uploads from the field app.