Comparison between Bluetooth and IrDA
| |
Bluetooth |
IrDA |
| Physical medium |
RF (radio) |
infrared light (850 nm) |
| Operating Frequency |
2.402 - 2.480 GHz (ISM band )
|
infrared light frequencies |
|
Data Rate |
1 Mbps (v1.1
or v1.2) *
3 Mbps (v2.0+EDR) |
115 kbps (SIR)
- 80 kbps effective
4 Mbps (FIR) - 3 Mbps effective
16 Mbps (VFIR) |
|
Range (Coverage) |
100 meters (Class 1)
20 meters (Class 2)
10 meters (Class 3) |
1
meter |
|
Topology |
point-to-point,
point-to-multipoint (star) |
point-to-point (**) |
|
Networking |
piconet, scatternet, PAN, LAN/WAN access |
direct connection, LAN (not used anymore) |
|
Connection states (***) |
active, park, hold, sniff |
(active or not active) |
|
Time for starting a new connection |
up to
10 seconds, depending on the number of available Bluetooth
devices within range |
< 1
second (500 ms average) |
|
Latency |
short
(1 ms), good for voice |
longer (typically 20 ms, but may reach hundreds milliseconds) |
|
IEEE standard |
802.15.1
(medium-rate Wireless PAN) |
- |
|
Security measures |
frequency hopping (FHSS): 1600 hops/second over 79 1-MHz-channels, 48-bit MAC address filtering,
non-discoverable mode, passkey (PIN) exchange (pairing), encryption |
line-of-sight (LOS), point-to-point, very short range,
30-degree cone, OBEX-based user authentication (user access
levels) |
|
Security risk |
when
Bluetooth is turned on and discoverable.
Known risks: computer-like virus. |
- |
|
Supported Profiles |
Generic Access, Service Discovery, Serial Port, OBEX, DUN, Object
Push, File Transfer, HID, HCRP, handsfree, audio gateway/headset,
LAN access/PAN, BIP, BPP, AVRCP, A2DP, SAP. |
Point
and Shoot, OBEX, File Transfer, Printing, Mobile
Communication, Payment |
|
Typical Applications |
cable replacement (e.g. keyboard, mouse, printer),
voice/telephony (e.g. headset), mobile device to PC synchronization, mobile phone as modem, and object
exchange (e.g. business card exchange, image transfer) |
spontaneous (ad-hoc) simple data transfer, e.g. payment, file
transfer, business card exchange; synchronization |
|
Advantage |
more
flexible, supports mobility because no need for LOS. |
Point-and-shoot is very easy, anyone can handle. |
|
Disadvantage |
Needs
start-up knowledge in device discovery, pairing, service
discovery, and COM port selection.
Longer connection setup. |
Always requires LOS position and within 30-degree cone of IrDA
beam. |
Notes:
- IEEE: Institute of Electrical and Electronics Engineers
- ISM: Industrial, Scientific, and Medical
- EDR: Enhanced Data Rate
- LOS : Line of Sight
- FSSS: Frequency Hopping Spread Spectrum
- OBEX: OBject EXchange
- SIR: Serial IrDA, FIR: Fast IrDA, VFIR: Very Fast IrDA
- PAN: Personal Area Network
- DUN: Dial-Up Networking
- HID: Human Interface Device
- HCRP: Hardcopy Cable Replacement Profile
- A2DP: Advanced Audio Distribution Profile
- AVRCP: Audio Video Remote Control Profile
- BIP: Basic Imaging Profile
- BPP: Basic Printing Profile
- SAP: SIM Access Profile
- (*) Effective rate: 432.6 kbps (symmetric) or 721 kbps upstream/57.6 kbps downstream (asymmetric).
- (**) Actually IrDA supports point-to-multipoint connection, but
because of the line-of-sight, 30-degree cone, and short-range
requirements, practically a typical IrDA connection is
point-to-point.
- (***) A.k.a. power (saving) modes.
|
