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# Sector

A `Sector` is a `bytes32` identifier for one bucket of a MultiVehicle's accounting: idle liquidity,
shares held in a sub-vehicle, assets parked aside, and so on. Every
[`moveBetweenSectors`](/actions/moveBetweenSectors) and [`dispatchVehicle`](/actions/dispatchVehicle)
call names the sectors it reads from and writes to.

```ts
import type { Sector } from '@railnetorg/railnet-sdk'

type Sector = Hex
```

## Static sectors

| Constant | Holds | Counted in `withdrawable()` |
| --- | --- | --- |
| `SECTOR_AVAILABLE` | Idle base asset, usable for sub-vehicle allocation and for the redeem queue | Yes |
| `SECTOR_ALLOCATION` | Vehicle shares received from settled deposits | No, it holds shares |
| `SECTOR_RESERVED` | Base asset the manager has explicitly parked aside | **No** |
| `SECTOR_ENTRY` | Virtual source for assets entering the system | Not tracked |
| `SECTOR_EXIT` | Virtual destination for assets leaving the system | Not tracked |

`SECTOR_RESERVED` is the one with teeth: assets moved there stay in `totalAssets()` but drop out of
`withdrawable()`, so neither auto-fulfillment nor the queue strategy engine can spend them. It is
asset-only — moving shares into it is rejected — and only an explicit move back to
`SECTOR_AVAILABLE` makes the liquidity spendable again.

## Vehicle sectors

Each sub-vehicle has its own sector, holding that vehicle's staged shares. The identifier is not the
address padded to 32 bytes: it is `0x01`, then eleven zero bytes, then the twenty address bytes.
Build it with `vehicleSector`, never by hand.

```ts
import { vehicleSector, sectorToVehicle, isVehicleSector } from '@railnetorg/railnet-sdk'

const sector = vehicleSector('0x2ec94b8979868Bf5586f8550733092A77Cd77c9E')
// 0x0100000000000000000000002ec94b8979868bf5586f8550733092a77cd77c9e

isVehicleSector(sector) // true
sectorToVehicle(sector) // 0x2ec94b8979868bf5586f8550733092a77cd77c9e
```

`sectorToVehicle` returns `undefined` for a static or query sector, so it doubles as a decoder when
reading sectors back from events.

## Query sectors

Queries in flight get their own temporary sectors, prefixed `0x02`. The SDK does not build these —
they are created and consumed by the protocol as a query progresses.