Lines Matching +full:header +full:- +full:payload
6 The Bluetooth Host implements all the higher-level protocols and
7 profiles, and most importantly, provides a high-level API for
17 Lowest down in the host stack sits a so-called HCI driver, which is
20 host, and vice-versa.
26 * Connection-oriented roles
32 * Connection-less roles
38 Each role comes with its own build-time configuration option:
41 connection-oriented roles central implicitly enables observer role, and
52 Most Zephyr-based BLE devices will most likely be peripheral-role
64 Central role may not be as common for Zephyr-based devices as peripheral
94 non-connectable, i.e. other device will not be able to connect to it.
111 Man-In-The-Middle (MITM) attacks, it is recommended to use some
112 out-of-band channel during the pairing. If the devices have a sufficient
116 a set of optional callbacks that can be used during the pairing - if the
143 using separate mesh-specific APIs.
151 so-called Connection-oriented Channels (CoC) mode. More information on
155 -----------
160 .. list-table::
161 :header-rows: 1
163 * - Term
164 - Description
166 * - Upper layer
167 - Layer above L2CAP, it exchanges data in form of SDUs. It may be an
170 * - Lower layer
171 - Layer below L2CAP, it exchanges data in form of PDUs (or fragments). It is
174 * - Service Data Unit (SDU)
175 - Packet of data that L2CAP exchanges with the upper layer.
180 * - Protocol Data Unit (PDU)
181 - Packet of data containing L2CAP data. PDUs always start with Basic L2CAP
182 header.
184 Types of PDUs for LE: :ref:`B-frames <bluetooth_l2cap_b_frame>` and
185 :ref:`K-frames <bluetooth_l2cap_k_frame>`.
187 Types of PDUs for BR/EDR: I-frames, S-frames, C-frames and G-frames.
189 * - Maximum Transmission Unit (MTU)
190 - Maximum size of an SDU that the upper layer is capable of accepting.
192 * - Maximum Payload Size (MPS)
193 - Maximum payload size that the L2CAP layer is capable of accepting.
195 In Basic L2CAP mode, the MTU size is equal to MPS. In credit-based
198 * - Basic L2CAP header
199 - Present at the beginning of each PDU. It contains two fields, the PDU
203 ---------
207 B-frame: Basic information frame
210 PDU used in Basic L2CAP mode. It contains the payload received from the upper
211 layer or delivered to the upper layer as its payload.
216 :alt: Representation of a B-frame PDU. The PDU is split into two rectangles,
217 the first one being the L2CAP header, its size is 4 octets and its made
219 the information payload and its size is less or equal to MPS.
223 K-frame: Credit-based frame
231 :alt: Representation of a starting K-frame PDU. The PDU is split into three
232 rectangles, the first one being the L2CAP header, its size is 4 octets
235 rectangle represents the information payload and its size is less or
236 equal to MPS minus 2 octets. The information payload contains the L2CAP
242 :alt: Representation of K-frames PDUs after the starting one. The PDU is split
243 into two rectangles, the first one being the L2CAP header, its size is 4
245 rectangle represents the information payload and its size is less or
246 equal to MPS. The information payload contains the L2CAP SDU.
249 ----------------
251 .. list-table::
252 :header-rows: 1
254 * - Kconfig symbol
255 - Description
257 * - :kconfig:option:`CONFIG_BT_BUF_ACL_RX_SIZE`
258 - Represents the MPS
260 * - :kconfig:option:`CONFIG_BT_L2CAP_TX_MTU`
261 - Represents the L2CAP MTU
263 * - :kconfig:option:`CONFIG_BT_L2CAP_DYNAMIC_CHANNEL`
264 - Enables LE Credit Based Flow Control and thus the stack may use
265 :ref:`K-frame <bluetooth_l2cap_k_frame>` PDUs
276 -----------
307 .. _bluetooth-persistent-storage:
317 .. code-block:: cfg