Pocket Minecraft Protocol

Unlike the Minecraft protocol, this protocol uses UDP with (so far observed, at least) one message per packet. This makes the protocol easier to work with when it comes to packet serialization, and might offer latency improvements, but will inevitably have the usual UDP issues (packets lost, truncated, duplicated, out-of-order, etc.).

Servers listen on UDP ports 19132-19135.

Clients don't pick any specific port to listen on.

Please note that even where packet field names are written in this page, these are still largely hypothetical and could well be incorrect guesses. Some packets are fixed to the RakNet protocol, and will be marked as "RakNet Packet", which means that these packets will not change on future versions.

It has been determined that PM uses RakNet for its networking library, some documentation that seems relevant.

Terminology

PM

Pocket Minecraft (aka Minecraft PE or Minecraft Pocket Edition)

Types

	Size	Range	Notes
byte	1	-128 to 127	Signed, two's complement
short	2	-32768 to 32767	Signed, two's complement
int32	4	-2147483648 to 2147483647	Signed, two's complement
int64	8		Maybe a double?
MAGIC	16	0x00ffff00fefefefefdfdfdfd12345678	always those hex bytes, corresponding to RakNet's default OFFLINE_MESSAGE_DATA_ID
string	= 1	N/A	Prefixed by a short containing the length of the string in characters. It appears that only the following ASCII characters can be displayed: !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~

Packets

All packets start with a single byte that identifies the packet type, the rest of the packet follows it.

ID_CONNECTED_PING_OPEN_CONNECTIONS (0x01)

Client to Broadcast

RakNet Packet

Packet ID	Field Name	Field Type	Example	Notes
0x01	Ping ID	int64	0x00000000003c6d0d	Time since start in Milliseconds
	MAGIC	MAGIC
Total Size:	25 Bytes

Clients start out by sending this packet to the IP broadcast address on port 19132 repeatedly (approx once per second) when joining a server was chosen on the main screen, and stops when the user selects a server (or leaves the screen). The ping ID from the client increases over time, and appears to be the number of milliseconds since the client program was started (might be used to measure server response latency).

ID_UNCONNECTED_PING_OPEN_CONNECTIONS (0x02)

Client to Broadcast

RakNet Packet

Packet ID	Field Name	Field Type	Example	Notes
0x02	Ping ID	int64	0x00000000003c6d0d	Time since start in Milliseconds
	MAGIC	MAGIC
Total Size:	25 Bytes

Same as ID_CONNECTED_PING_OPEN_CONNECTIONS (0x01), but with the Packet ID changed.

ID_OPEN_CONNECTION_REQUEST_1 (0x05)

Client to Server

RakNet Packet

Packet ID	Field Name	Field Type	Example	Notes
0x05	MAGIC	MAGIC
	Protocol Version	byte	5	Check the Data Packet section for the current version
	Null Payload	many 0x00 bytes	0x00 * 1447	MTU (Maximum Transport Unit)
Total Size:	18 Bytes + length of Null Payload

If the version is different than yours, reply with a ID_INCOMPATIBLE_PROTOCOL_VERSION (0x1A)

Sent from client after it receives packet 0x1d. The client will repeatedly send this with reducing sizes until it successfully receives a reply. Observed behaviour is that the client will send packets ~0.5s apart in the following way, until it gets a 0x06 response packet, or reaches the end of these:

• 4 packets of Null Payload length of 1447
• 4 packets of Null Payload length of 1155
• 5 packets of Null Payload length of 531

If the server doesnt't reply the client, the client will display a "Connect Error" window

ID_OPEN_CONNECTION_REPLY_1 (0x06)

Server to Client

RakNet Packet

Packet ID	Field Name	Field Type	Example	Notes
0x06	MAGIC	MAGIC
	Server ID	int64	0x00000000372cdc9e	This value seems to be constant for an installation of PM, or differs between the demo and full version.
	Server Security	byte	0	Always 0
	MTU Size	short	1447	length of 0x05. Used to determine packet loss and max UDP packet size (MTU)
Total Size:	28 Bytes

Sent from server after it receives packet 0x05.

ID_OPEN_CONNECTION_REQUEST_2 (0x07)

Client to Server

RakNet Packet

Packet ID	Field Name	Field Type	Example	Notes
0x07	MAGIC	MAGIC
	Security + Cookie	1 + 4 bytes	0x043f57fefd	Unused, constant value
	Server UDP Port	short	19132
	MTU Size	short	1464
	Client ID	int64	0x00000000372cdc9e	The Client / Server ID will be the same for a given device
Total Size:	34 Bytes

Sent from client in response to packet 0x06.

ID_OPEN_CONNECTION_REPLY_2 (0x08)

Server to Client

RakNet Packet

Packet ID	Field Name	Field Type	Example	Notes
0x08	MAGIC	MAGIC
	Server ID	int64	0x00000000372cdc9e
	Client UDP Port	short	46946
	MTU Size	short	1464
	Security	byte	0	Always 0
Total Size:	30 Bytes

Sent from server in response to packet 0x07.

ID_INCOMPATIBLE_PROTOCOL_VERSION (0x1A)

Server to Client

RakNet Packet

Packet ID	Field Name	Field Type	Example	Notes
0x1A	Protocol Version	byte	5
	MAGIC	MAGIC
	Server ID	int64	0x00000000372cdc9e
Total Size:	26 Bytes

ID_UNCONNECTED_PING_OPEN_CONNECTIONS (0x1C)

Server to Client

RakNet Packet

Packet ID	Field Name	Field Type	Example	Notes
0x1C	Ping ID	int64	0x00000000003c6d0d	Time since start in Milliseconds
	Server ID	int64	0x00000000372cdc9e
	MAGIC	MAGIC
	Identifier	string	MCCPP;Demo;Steve
Total Size:	46 Bytes + Server name length

Server sends this packet in response to a 0x02 packet. Depends of the version to send a 0x1D or a 0x1C If the Server is invisible, this packet will be sent without username

Minecraft Pocket Edition v0.5.0.0 introduced another identifier special for Minecon 2012 "MCCPP;MINECON;". This will show a Minecon logo in front of the server name, and the color of the name is changed to blue.

ID_ADVERTISE_SYSTEM (0x1D)

Server to Client

RakNet Packet

Packet ID	Field Name	Field Type	Example	Notes
0x1D	Ping ID	int64	0x00000000003c6d0d	Time since start in Milliseconds
	Server ID	int64	0x00000000372cdc9e
	MAGIC	MAGIC
	Data	string	MCCPP;Demo;Steve	Used to send the username (MCCPP;Demo; + username)
Total Size:	35 Bytes + length of string

Same as ID_UNCONNECTED_PING_OPEN_CONNECTIONS (0x1C), but with the Packet ID changed. Depends of the version to send a 0x1D or a 0x1C

Custom Packet (0x80-0x8F)

Two-Way

This packet is part of the real Minecraft PE implementation. The structure can change anytime.

Packet ID	Field Name	Field Type	Example	Notes
0x80-0x8F	Count	3 bytes	0	Increments once every packet.
	Data payload		0x40009000000009...	Uses Packet Encapsulation format
Total Size:	6 Bytes + payload

The receiver will use the Packet number in the 0xC0 packet and send it back.

NACK (0xA0)

Two-Way

This packet is part of the real Minecraft PE implementation. The structure can change anytime.

Packet ID	Field Name	Field Type	Example	Notes
0xN0	Unknown	short	1
	Additional Packet	boolean	true	true when there is only one packet received
	Packet Number	3 bytes	0x000000	Packet to resend
	Packet Number #2	3 bytes	0x000004	Aditional packet to resend (only when false)
Total Size:	7 or 10 Bytes

Send these when a packet was lost, or reply to this resending the lost packet.

ACK (0xC0)

Two-Way

This packet is part of the real Minecraft PE implementation. The structure can change anytime.

Packet ID	Field Name	Field Type	Example	Notes
0xC0	Unknown	short	1
	Additional Packet	boolean	true	true when there is only one packet received
	Packet Number	3 bytes	0x000000	Received packet number from field Count in 0x84 and 0x8C
	Packet Number #2	3 bytes	0x000004	Last received packet number (only when false)
Total Size:	7 or 10 Bytes

Sent after a 0x8X. It's used to ACK recieval of packets. The second packet number is optional and only there when bool is false.

Packet Encapsulation format

The payload in 0x80-0x8F packets is encoded using different schemes. To decode them, you've to use the Encapsulation ID to check wich type you should use. The Encapsulation ID is the first byte of the payload.

Multiple Data Encapsulation packets could be present in one packet. If you want to send data, use 0x00

Calculate length in bytes:

real length = length / 8

0x00

Encapsulation ID	Field Name	Field Type	Example	Notes
0x00	length	short	0x0090	Length of Packet in bits
	Packet	Data Packet	0x09d92145...
Total Size:	3 Bytes + Packet Data length

0x40

Encapsulation ID	Field Name	Field Type	Example	Notes
0x40	length	short	0x0090	Length of Packet in bits
	Count	3 bytes	0x000000	Unknown use
	Packet	Data Packet	0x09d92145...
Total Size:	6 Bytes + Packet Data length

0x60

Encapsulation ID	Field Name	Field Type	Example	Notes
0x60	length	short	0x0090	Length of Packet in bits
	Count	3 bytes	0x000000	Unknown use
	Unknown	4 bytes	0x00000000	Only sent on first iteration
	Packet	Data Packet	0x09d92145...
Total Size:	12 Bytes + Packet Data length

Data Packets

This information has been generated using PocketBurger, then edited manually.

Minecraft: Pocket Edition v0.7.3, protocol #11

LoginPacket (0x82)

Server to Client

Packet ID	Field Name	Field Type	Notes
0x82	Username	string8
	Protocol #1	int
	Protocol #2	int
	ClientID	int
	Realms Data	string8

LoginStatusPacket (0x83)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x83	a	int

ReadyPacket (0x84)

Server to Client

Packet ID	Field Name	Field Type	Notes
0x84	bits[8](a)	byte[]

MessagePacket (0x85)

Two-Way

Packet ID	Field Name	Field Type	Notes
0x85	a	string8

SetTimePacket (0x86)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x86	a	int

StartGamePacket (0x87)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x87	a	int
	b	int
	c	int
	d	int
	e	float
	f	float
	g	float

AddMobPacket (0x88)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x88	a	int
	b	int
	c	float
	d	float
	e	float
	f.degreesToChar()	byte
	g.degreesToChar()	byte
	Metadata(h)	byte[]

AddPlayerPacket (0x89)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x89	(unsigned) a	long
	b	string8
	c	int
	d	float
	e	float
	f	float
	g.degreesToChar()	byte
	h.degreesToChar()	byte
	i	short
	j	short
	Metadata(k)	byte[]

RemovePlayerPacket (0x8a)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x8a	a	int
	(unsigned) b	long

AddEntityPacket (0x8c)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x8c	a	int
	(unsigned) b	byte
	c	float
	d	float
	e	float
	f	int
	g.clamp()	short
	h	short
	i	short

RemoveEntityPacket (0x8d)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x8d	a	int

AddItemEntityPacket (0x8e)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x8e	a	int
	b	short
	(unsigned) c	byte
	d	short
	e	float
	f	float
	g	float
	h	byte
	i	byte
	j	byte

TakeItemEntityPacket (0x8f)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x8f	a	int
	b	int

MoveEntityPacket (0x90)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x90

MoveEntityPacket_PosRot (0x93)

None

Packet ID	Field Name	Field Type	Notes
0x93	a	int
	b	float
	c	float
	d	float
	e	float
	f	float

MovePlayerPacket (0x94)

Two-Way

Packet ID	Field Name	Field Type	Notes
0x94	a	int
	b	float
	c	float
	d	float
	e	float
	f	float

PlaceBlockPacket (0x95)

None

Packet ID	Field Name	Field Type	Notes
0x95	a	int
	b	int
	c	int
	(unsigned) d	byte
	(unsigned) e	byte
	(unsigned) f	byte
	(unsigned) g	byte

RemoveBlockPacket (0x96)

Server to Client

Packet ID	Field Name	Field Type	Notes
0x96	a	int
	b	int
	c	int
	(unsigned) d	byte

UpdateBlockPacket (0x97)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x97	a	int
	b	int
	(unsigned) c	byte
	(unsigned) d	byte
	(unsigned) e	byte

AddPaintingPacket (0x98)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x98	a	int
	b	int
	c	int
	d	int
	e	int
	f	string8

ExplodePacket (0x99)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x99	a	float
	b	float
	c	float
	d	float
	e	int
	f	byte
	g	byte
	h	byte

LevelEventPacket (0x9a)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x9a	a	short
	b	short
	c	short
	d	short
	e	int

TileEventPacket (0x9b)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x9b	a	int
	b	int
	c	int
	d	int
	e	int

EntityEventPacket (0x9c)

Two-Way

Packet ID	Field Name	Field Type	Notes
0x9c	a	int
	(unsigned) b	byte

RequestChunkPacket (0x9d)

Server to Client

Packet ID	Field Name	Field Type	Notes
0x9d	a	int
	b	int

ChunkDataPacket (0x9e)

Client to Server

Packet ID	Field Name	Field Type	Notes
0x9e	a	int
	b	int
	(unsigned) c	byte
	d	byte[]
	e	byte[]

PlayerEquipmentPacket (0x9f)

Two-Way

Packet ID	Field Name	Field Type	Notes
0x9f	a	int
	(unsigned) b	short
	(unsigned) c	short
	d	byte

PlayerArmorEquipmentPacket (0xa0)

Two-Way

Packet ID	Field Name	Field Type	Notes
0xa0	a	int
	b	byte
	c	byte
	d	byte
	e	byte

InteractPacket (0xa1)

Two-Way

Packet ID	Field Name	Field Type	Notes
0xa1	bits[8](a)	byte[]
	b	int
	c	int

UseItemPacket (0xa2)

Server to Client

Packet ID	Field Name	Field Type	Notes
0xa2	a	int
	b	int
	c	int
	d	int
	bits[16](e).reverseBytes()	byte[]
	(unsigned) f	byte
	g	int
	h	float
	i	float
	j	float
	k	float
	l	float
	m	float

PlayerActionPacket (0xa3)

Server to Client

Packet ID	Field Name	Field Type	Notes
0xa3	a	int
	b	int
	c	int
	d	int
	e	int
	f	int

HurtArmorPacket (0xa5)

Client to Server

Packet ID	Field Name	Field Type	Notes
0xa5	a	byte

SetEntityDataPacket (0xa6)

Client to Server

Packet ID	Field Name	Field Type	Notes
0xa6	a	int
	Metadata(b)	byte[]

SetEntityMotionPacket (0xa7)

Client to Server

Packet ID	Field Name	Field Type	Notes
0xa7	(unsigned) a.clamp()	byte
	b	int
	c	short
	d	short
	e	short

SetRidingPacket (0xa8)

Client to Server

Packet ID	Field Name	Field Type	Notes
0xa8	a	int
	b	int

SetHealthPacket (0xa9)

Two-Way

Packet ID	Field Name	Field Type	Notes
0xa9	a	byte

SetSpawnPositionPacket (0xaa)

Client to Server

Packet ID	Field Name	Field Type	Notes
0xaa	a	int
	b	int
	(unsigned) c	byte

AnimatePacket (0xab)

Two-Way

Packet ID	Field Name	Field Type	Notes
0xab	bits[8](a)	byte[]
	b	int

RespawnPacket (0xac)

Two-Way

Packet ID	Field Name	Field Type	Notes
0xac	a	int
	b	float
	c	float
	d	float

SendInventoryPacket (0xad)

None

Packet ID	Field Name	Field Type	Notes
0xad	a	int
	(unsigned) b	byte
	c	short
	Item(d)	byte[]
	Item(e)	byte[]

DropItemPacket (0xae)

Server to Client

Packet ID	Field Name	Field Type	Notes
0xae	a	int
	(unsigned) b	byte
	Item(c)	byte[]

ContainerOpenPacket (0xaf)

Client to Server

Packet ID	Field Name	Field Type	Notes
0xaf	(unsigned) a	byte
	(unsigned) b	byte
	(unsigned) c	byte
	d	string8

ContainerClosePacket (0xb0)

Two-Way

Packet ID	Field Name	Field Type	Notes
0xb0	(unsigned) a	byte

ContainerSetSlotPacket (0xb1)

Two-Way

Packet ID	Field Name	Field Type	Notes
0xb1	bits[8](a)	byte[]
	bits[16](b).reverseBytes()	byte[]
	Item(c)	byte[]

ContainerSetDataPacket (0xb2)

Client to Server

Packet ID	Field Name	Field Type	Notes
0xb2	(unsigned) a	byte
	b	short
	c	short

ContainerSetContentPacket (0xb3)

Client to Server

Packet ID	Field Name	Field Type	Notes
0xb3	(unsigned) a	byte
	b	short
	Item(c)	byte[]

ContainerAckPacket (0xb4)

None

Packet ID	Field Name	Field Type	Notes
0xb4	(unsigned) a	byte
	b	short

ChatPacket (0xb5)

Client to Server

Packet ID	Field Name	Field Type	Notes
0xb5	a	string8

SignUpdatePacket (0xb6)

Two-Way

Packet ID	Field Name	Field Type	Notes
0xb6	a	short
	(unsigned) b	byte
	c	short
	d	string8

AdventureSettingsPacket (0xb7)

Client to Server

Packet ID	Field Name	Field Type	Notes
0xb7	bits[32](a).reverseBytes()	byte[]