NFD

# FIB Management

**FIB Management** is a module of [[Management|NFD Management protocol]].

It provides:

* commands to insert, update, and delete FIB entries and nexthop records

* a dataset of FIB entries and nexthop records

FIB Management commands and datasets are published in namespace `ndn:/localhost/nfd/fib`.

## Control Commands

[[ControlCommand]] **management-module**: `fib`

### Add a nexthop

**command-verb**: `add-nexthop`

This command adds a nexthop to a FIB entry.

If the FIB entry does not exist, it is inserted automatically.

ControlParameters fields:

* Name (required)

* FaceId (required)

* Cost (optional)

FaceId is the FaceId returned in [[FaceMgmt|Face Management]].

If FaceId is set to zero, it is implied as the face of the entity sending this command.  

If face does not exist, the command fails with code 410.

Cost defaults to zero.

If a nexthop of same FaceId exists on the FIB entry, its cost is updated.

### Remove a nexthop

**command-verb**: `remove-nexthop`

This command removes a nexthop from a FIB entry.

If the last nexthop record in a FIB entry is removed, the FIB entry is deleted automatically.

ControlParameters fields:

* Name (required)

* FaceId (required)

FaceId is the FaceId returned in [[FaceMgmt|Face Management]].

If FaceId is set to zero, it is implied as the face of the entity sending this command.

If the FIB entry does not exist, the command fails with code 404.

If face or nexthop record does not exist, this command does nothing, but is still considered successful.

## FIB Dataset

FIB entries and nexthop records are published as a [[StatusDataset|Status Dataset]] at `ndn:/localhost/nfd/fib/list`.

Each FIB entry is represented by a **FibEntry** blocks:

    FibEntry      := FIB-ENTRY-TYPE TLV-LENGTH

                       Name

                       NextHopRecord+

    NextHopRecord := NEXT-HOP-RECORD TLV-LENGTH

                       FaceId

                       Cost

## TLV-TYPE assignments

Type                                        | Assigned value    | Assigned value (hex)

------------------------------------------- | ----------------- | --------------------

FibEntry                                    | 128               | 0x80

NextHopRecord                               | 129               | 0x81