3GP: the 3G Video Standard

Introduction
3GP or .3gp is the third generation video standard. It integrates mp3, mp4, 3gpp, 3g3p and 3g2.

What is 3GP?
3GP is a multimedia container format defined by 3GPP for use on 3G mobile phones. It is a simplified version of MPEG-4 Part 14 (MP4). 3GP files have the filename extension .3gp or .3g2.

3GP stores video streams as MPEG-4 or H.263, and audio streams as AMR-NB or AAC-LC formats. 3GP files are always big-endian. 3GP also describes image sizes and bandwidth, so content is correctly sized for mobile display screens.

3GP files are viewable on a PC using programs like QuickTime or RealPlayer.

MPEG-4 Part 14, formally, ISO/IEC 14496-14:2003, is a multimedia container format standard specified as a part of MPEG-4. It is most-commonly used to store digital audio and digital video streams, especially those defined by MPEG, but also can be used to store other data such as subtitles and still images. Like most modern container formats, MPEG-4 Part 14 allows streaming over the Internet. The official filename extension for MPEG-4 Part 14 files is .mp4, thus the container format is often refered to simply as MP4.

3GPP
The 3rd Generation Partnership Project (3GPP) is a collaboration agreement that was established in December 1998. It's a co-operation between ETSI (Europe), ARIB/TTC (Japan), CCSA (China), ATIS (North America) and TTA (South Korea).

Some of the well well-known participants of the 3GPP project are 3, Alvatel Apple, AT&T, BenQ, BT Group, China Mobile Com, Congular Wireless, Cisco, Ericsson, France Telecom, Fraunhofer, Fujitsu, HP, HuaWei, IBM, Intel, KDDI, KPN, LG, Lucent, Microsoft, Mitsubishi, Motorola, NEC, Nippon Ericsson, Nokia, Nortel, NTT DoCoMo, 02, Oki, Panasonic, Philips, Qualcomm, Samsung, Sharp, Siemens, Sony Ericsson, Sun, Swisscom, Tata Consultancy Services, Texas Instruments, Thomson, T-Mobile, TNO, Toshiba, VIA Technologies , Vodafone and Yokogawa, to name but a few.

The scope of 3GPP is to make a globally applicable third generation (3G) mobile phone system specification within the scope of the ITU's IMT-2000 project. 3GPP specifications are based on evolved GSM specifications, now generally known as the UMTS system.

Note that 3GPP should not be confused with 3GPP2, which specifies standards for another 3G technology based on IS-95 (CDMA), commonly known as CDMA2000.

Standards

3GPP standards are structured as Releases. Discussion of 3GPP thus freqently refers to the functionality in one release or another.

  • Release 98 and earlier releases specify pre-3G GSM networks.
  • Release 99 specify the first UMTS 3G networks, incorporating a CDMA air interface.
  • Release 4 - originally Release 2000 - adds features including an All IP Core Network.
  • Release 5 introduces IMS and HSDPA.
  • Release 6 integrates operation with Wireless LAN networks and adds HSUPA.
  • Release 7 and onwards are still in the early stages, and work towards better integration with wired networks.

Each Release incorporates hundreds of individual standards documents, each of which may have been through many revisions.

Current 3GPP standards incorporate the latest revision of the GSM standards. 3GPP documents are made available freely on the organisation's web site. Whilst 3GPP standards can be bewildering to the newcomer, they are a remarkably complete and detailed resource and provide insight into how the cellular industry works. They cover not only the radio part ("Air Interface") and Core Network, but also billing information and speech coding down to source code level. Cryptographic aspects (authentication, confidentiality) are also freely specified in detail. 3GPP2 offer similar information about their system.

Deployment

3GPP systems are deployed across much of the established GSM market (primarily Release 99 systems to date). As of 2005, 3GPP systems are seeing deployment in the same markets as 3GPP2 systems (for example, North America). Industry commentators speculate constantly about the competing systems, with the outcome far from clear.

3GPP specification

The term "3GPP specification" covers all GSM (including GPRS and EDGE) and W-CDMA specifications. The following terms are also used to describe networks using the 3G specifications: UTRAN, UMTS (in Europe) and FOMA (in Japan). Revised versions of many of these specifications are produced up to four times a year following the quarterly TSG plenary meetings. (TSG GERAN meets five times a year.) See the table below which gives links to lists of specifications arising from each plenary TSG meeting since the freezing of Release 1999. The month of the meeting and the meeting number are shown in each case. Note that the tables show only those specifications newly approved or modified at the meeting concerned; they do not contain a complete list of all specifications current following the meeting. For such a list, consult the "status list" - see below.

Following each TSG SA plenary meeting, a complete set of specifications is produced. This set includes not only the new specifications generated at that meeting, but also the latest versions of each specification that was not changed at that meeting. i.e. each directory holds a complete set of specifications. Each set has an associated status list as detailed in the table below. Each set (and corresponding status list) includes the specs arising from the TSG GERAN meetings held since the preceding SA meeting. (GERAN meets asynchronously from the other TSGs.)

The Status List (ZIPped RTF or Word format) summarizes the current version number for every release of every 3GPP specification following each TSG plenary meeting. Also listed for each specifications are:
  • the 3GPP working group and rapporteur responsible for the specification
  • the Project Manager in MCC (Mobile Competence Centre) responsible for the specification
  • the meeting at which it was, or is expected to be, "frozen" (i.e. the point after which only corrections are allowed)
Full details of the Specifications, their history and current status can be found in the 3GPP Specifications Status database at 3GPP.org.


More about 3GP
See Wikipedia