This figure appears as a series of horizontal layers. Divisions at the top begin at the left-most edge with 0 and continue rightwards at regular intervals to 8, 16, and 24. The right-most edge is unlabeled.
| Type = 9 | Code = 0 | Checksum | |
| Router address | |||
| Type = 16 | Length | Sequence number | |
| Registration lifetime | RBHFMGrT bits | Reserved | |
| 0 or more care-of addresses | |||
Below the last layer is an ellipsis followed by an empty layer. The first four layers are designated as "Standard ICMP fields." The rest is designated as "Mobility agent advertisement extension."