1 oFono - Open Source Telephony
2 *****************************
4 Copyright (C) 2008-2011 Intel Corporation. All rights reserved.
10 The overall goal of the oFono project is to create a telephony host stack
11 for embedded/mobile and desktop systems based on Linux.
13 It currently targets GSM/UMTS User Equipment (UE) based on 3GPP standards,
14 but is of course not limited to that. Extensions for other telephony systems
15 like CDMA/EVDO are more than welcome.
17 Within oFono there is clear abstraction between the application interfaces
18 based on D-Bus, the hardware level (via drivers) and the integration with
19 other system components (plugins). The whole architecture is modular and
26 The oFono stack will support the majority of the features from the 3GPP
27 specification, but not all of them. The whole standard is pretty complex
28 and some features are not used in any mobile network so far, some of them
29 are outdated and have no relevance anymore. This paragraph tries to give
30 some insights on what has been implemented so far, what is coming in the
31 future and especially what will not be part of oFono.
33 Current implemented features:
37 Currently there are two modem drivers available.
39 The "atmodem" driver handles hardware based on the 3GPP
42 The "isimodem" driver handles Nokia based PhoNet modems.
46 The network registration interface contains support for
47 network detection. It also handles the automatic or manual
48 registration to a mobile network.
50 Additional information about the current network can be
51 easily retrieved and displayed to the user.
53 Network time indications
55 oFono includes support for receiving Network Identity and
56 Timezone (NITZ) indications, and handles processing of
57 this information via system-specific plugins.
59 An example network time plugin is provided that simply
60 prints out the received time information. A more advanced,
61 real-world plugin could automatically set the system time
62 based on the received information.
66 The voice call interface handles simple call creation and
67 termination. It also supports 3way-calling and multi-party
70 This is only for voice control. It doesn't contain support
71 for the voice data path/routing.
73 Advanced voice call control
75 Features like COLR/CLIR/CLIP/COLP are supported by the
76 voice call handling interface.
78 The support for call forwarding and call waiting is also
81 Interfaces for call barring and advice of charge do exist,
82 but highly depend on if the operator supports them.
86 The call history is realized via a plugin interface and
87 not handled directly. This allows an easy integration with
88 storage systems like Evolution-Data-Server.
92 The storage of the SIM card is not used. The only supported
93 feature is to export the contacts stored on the SIM card to
94 some third-part entity.
96 SIM card storage is limited, slow and not flexible enough
97 for modem telephony applications.
101 The SMS support for text messages is available. oFono
102 supports concatenated messages of up to 255 segments, UCS2 and
103 GSM alphabets as well as extended alphabets. Delivery
104 confirmations (Status Reports) are also supported.
106 Selection of SMS bearer settings is supported through the
107 'Bearer' property on the SmsManager interface.
111 SIM PIN locks, network and service provider locks are
112 supported. The SIM Manager also handles retry counter for PIN,
117 Cell broadcasts should be fully supported by oFono, but have
118 not been well tested. Base station name ids have been
123 GPRS data connections are fully supported by oFono. Multiple
124 active GPRS contexts are supported. IPv6 context support is
127 Radio Access Settings
129 The radio settings interface contains support for selecting
130 the access selection mode and used frequency bands, and allows
131 enabling and disabling fast dormancy on hardware that support
136 The Sim Toolkit interface handles the SAT commands. Sim Toolkit
137 relies on the SimToolkit agent not only to get confirmation
138 from the user but also to inform user of the SAT initiated
139 operation status. Information on the Sim Toolkit feature
140 list can be found in features.txt.
142 Supplementary Services
144 The Supplementary Services interface handles both recognized
145 supplementary service control string and user/network initiated
146 unstructured supplementary service data (USSD).
148 GPS/Location Services
150 oFono provides a Location Reporting interface that enables
151 taking advantage of on-board GPS capabilities of modern modems.
152 oFono also provides an Assisted Satellite Navigation interface
153 that allows feeding assistance data to the GPS unit from the
154 network as well as E911 services.
156 Work in progress features:
160 IPv6 PS context support is under development.
164 To enable DialUp Networking (over Bluetooth or USB), and to
165 allow Bluetooth HandsFree / Headset support, oFono will expose
166 some 'fake' modem to enable the communication with car kits, or
169 Not implemented features:
173 The SIM card storage will not be used by oFono. It is slow,
174 limited in size and flexibility. It is an outdated interface
175 that makes no sense in a modern telephony system.
177 Export of stored contacts from the SIM card is supported for
178 legacy reasons and to allow a smooth transition.
182 The WAP feature is outdated and using full Internet access
183 with an embedded browser is the future.
187 The MMS support should not be part of oFono itself. The best
188 idea is to implement a MMS service that runs in the user
189 session and uses oFono's SMS interface to listen for
192 Similar to the split between BlueZ and OBEX daemon.
194 Especially when it comes to image conversion and other tasks
195 that MMS support requires it is important to NOT do this as
200 This is an Ericsson specific standard and not widely spread
201 across the handset manufactures.
205 Currently there are no plans to support this. The support
206 from the networks and available handsets are still limited.
208 This needs re-evaluation once such a service becomes more
211 A similar split like with MMS might be a good idea.