1. Personal Health Device WG
Transport Issues

2. Transport Adaptation Layer
11073 Protocol Stack
Application Profiles
Application Layer
Services
Transport Adaptation Layer
Proprietary
Wireless
Link
layer
Zigbee
TCP/IP
Bluetooth
RS232

3. Logical Link Control Adaptation Protocol (L2CAP)
Protocol Stack
Application
layer
Application Profiles
Other
Service
discovery
RFComm
Telephony
Middleware
layer
LLC
Control
Audio
Logical Link Control Adaptation Protocol (L2CAP)
Data
Link
layer
Link manager
Baseband
The protocol stack does not follow the normal OSI model, and in addition to the lower layers, defines a set of specialised application services and profiles built on top of the functions of the lower layers. It also has services designed to be real time (audio).
Physical radio – Uses rapid pseudo-random frequency hopping in the 2.4GHz band on 79 channels using frequency shift keying (FSK) to give 1Mbps gross bit rate. The hops are specific to a piconet and determined by the master. Master and all slaves follow the hopping sequence. The hops are every 625 μs (1600/s) and 250 μs are used to allow the receiver to settle, so only 366 bits are left for transmission, although the frequency will remain fixed for the duration of a complete packet. There is also significant overhead in each packet further reducing throughput. It can interfere with
Baseband – this defines frame format, state model for the radio connection, command protocol. It establishes a link between master and each slave and supports two
Link manager – performs authentication, encryption
L2CAP – has three functions; performs fragmentation of 64k blocks passed from higher layers; handles multiplexing of streams from different sources; QoS and establishes maximum packet size for link. It is connection-oriented.
Physical
layer
Physical radio

4. Simple point to point link
Communication
Application
Profiles
Application
Profiles
Application
Layer
Application
Layer
Transport
Adaptation
Layer
Transport
Adaptation
Layer
Link
Link
Simple point to point link

5. Bridging identical point to point links
Communication 1
Application
Profiles
Application
Profiles
Application
Layer
Application
Layer
Transport
Adaptation
Layer
Transport
Adaptation
Layer
Bridge
Link
Link
Link
Link
Bridging identical point to point links

6. Relaying dissimilar point to point links
Communication 2
Application
Profiles
Application
Profiles
Application
Layer
Application
Layer
Relay
Transport
Adaptation
Layer
Transport
Adaptation
Layer
Transport
Adaptation
Layer
Transport
Adaptation
Layer
Link
Link
Link
Link
Relaying dissimilar point to point links

7. Spanning dissimilar technologies perhaps with filter
Communication 3
Application
Profiles
Application
Profiles
Filter
Application
Layer
Application
Layer
Appl
Appl
Transport
Adaptation
Layer
Transport
Adaptation
Layer
Transport
Adaptation
Layer
Transport
Adaptation
Layer
Link
Link
Link
Link
Spanning dissimilar technologies perhaps with filter

8. Error control Flow control ACK vs ACKless
Transport Layer Characteristics
Error control
Flow control
ACK vs ACKless

9. Link Layer Characteristics
Error control
Flow control
Serial vs packet
1 message per packet
Packet size
Connection oriented vs connectionless
Device discovery
Topology (Peer, Piconet, point to point)