Logical Link Control

​​Assigned Numbers are used in the Logical Link Control for protocol/service multiplexers.

Channel Identifiers

The predefined L2CAP Channel Identifiers can be found within the Bluetooth® Core Specification, in Volume 3, Part A - Logical Link Control and Adaptation Protocol Specification.

Protocol and Service Multiplexers (PSMs)

Protocol PSM Reference
SDP 0x0001 See Bluetooth Service Discovery Protocol (SDP), Bluetooth SIG
RFCOMM 0x0003 See RFCOMM with TS 07.10, Bluetooth SIG
TCS-BIN 0x0005 See Bluetooth Telephony Control Specification / TCS Binary, Bluetooth SIG
TCS-BIN-CORDLESS 0x0007 See Bluetooth Telephony Control Specification / TCS Binary, Bluetooth SIG
BNEP 0x000F See Bluetooth Network Encapsulation Protocol, Bluetooth SIG
HID_Control 0x0011 See Human Interface Device, Bluetooth SIG
HID_Interrupt 0x0013 See Human Interface Device, Bluetooth SIG
UPnP 0x0015 See [ESDP] , Bluetooth SIG
AVCTP 0x0017 See Audio/Video Control Transport Protocol, Bluetooth SIG
AVDTP 0x0019 See Audio/Video Distribution Transport Protocol, Bluetooth SIG
AVCTP_Browsing 0x001B See Audio/Video Remote Control Profile, Bluetooth SIG
UDI_C-Plane 0x001D See the Unrestricted Digital Information Profile [UDI], Bluetooth SIG
ATT 0x001F See Bluetooth Core Specification.​​
​3DSP 0x0021​ ​​See 3D Synchronization Profile, Bluetooth SIG.
​LE_PSM_IPSP ​0x0023 See Internet Protocol Support Profile (IPSP), Bluetooth SIG
OTS  0x0025 See Object Transfer Service (OTS), Bluetooth SIG 

CID Name Space

The CID name space for the ACL-U, AMP-U, and LE-U logical links that are defined can be found within the Bluetooth Core Specification in Volume 3, Part A - Logical link Control and Adaptation Protocol Specification.

The ACL-U and AMP-U CID Name Space

Value(s) Reference for Definitions
0x0000-0xFFFF Bluetooth Core Specification
Vol 3, Part A, section 2.1 (v2.1 + EDR, 3.0 + HS and 4.0, 4.1), Table 2.1

The LE-U  CID Name Space

Value(s) Reference for Definitions
0x0000-0x001F Bluetooth Core Specification
Vol 3, Part A, section 2.1 (v2.1 + EDR, 3.0 + HS and 4.0, 4.1), Table 2.2
0x0020-0x003E Reserved for future use
0x003F-0xFFFF Bluetooth Core Specification
Vol 3, Part A, section 2.1 (v2.1 + EDR, 3.0 + HS and 4.0, 4.1), Table 2.2