Sony Ericsson start guide, newbie knowledge base

Some terms that you may want to know:

All SE phones are basically broken down into groups. You'll need to find out your phone's Platform, CID, EROM, Colour and Firmware version.

CID is basically the protection system used on your phone, it determines the loaders used to break into it Current CIDs in use by SE are 29/36/37/49/50/51/52/53
The most common CIDs are 36, 49, 51/52, 53 The most modifications that are available on SE-NSE can be applied to the above mentioned CIDs, apart from 53, which is still under research and development, but there are tools that work with this type of CID

CDA defines which variant of a specific firmware a phone is supposed to have. It lets among others SEUS (Sony Ericsson Update Service) know which language-pack/branding/bandlocks a phone is to be flashed with. A generic (unbranded) K750 for use in Scandinavia will be CDA102337/12, whilst a Telenor-branded K750 will be CDA102338/62. Both will be flashed with the same languages/dictionaries, but the latter will be flashed with Telenor-branded firmware.

EROM is Extended ROM. This is the base part of the software which isn't flashed in normal update operations. It controls the flashing interface, the boot loader, etc.
EROM Colour:This "colour" defines what kind of phone you have.
RED Phones are typical retail phones
BROWN phones are phones used in development and testing
BLUE phones are the units that were assembled at the factory but never programmed with firmware/IMEI/GDFS

GDFS is the phones "stash", where all settings and calibration data is stored (this also goes for the firmwares IMEI-resource as well as the SIMlocks). Similar to other brands use of NVRAM (Non-Viotile Random Access Memory). It should be noted that in SE-based phones, the IMEI is stored in two places, the OTP (One Time Programmable memory) and GDFS. The GDFS IMEI is normally read from the OTP, but this can be circumvented by SETool function to "change" the IMEI. This patches the firmware into allowing different OTP/GDFS IMEIs. It is the GDFS IMEI that is reported to the network, so changing this will "de-bar" blocked phones. SEUS is not fooled by this, on the other hand, and it should also be noted that doing this is illegal in most countries.

PLATFORM is the hardware 'chipset' used in the mobile you own. DB2000, DB2010, DB2020, DB3150 are the most common platforms, and DB2010 to DB3150 are supported by most free tools

FIRMWARE is the 'operating system' of your phone, it is divided into two parts; MAIN Firmware and FS (File System). The FS contains the system files that are required for operation of the phone itself, and the MAIN is the actual operating environment.

EMMA = Service software/solution by SE themselves. Protected by the EMMA smartcard to prevent non-licensed usage. Current version is EMMA3, though EMMA2 is still alive (but kinda useless on newer phones). The EMMA smartcard contains an algorithm that allows EMMA to communicate directly to/with the phones CID, so performing operations the way they were intended. The smartcard and its algorithm has not been cracked. Current EMMA access levels exists:Service Update - Can't unlock phones.Service Update Pro - Can't unlock phones.Network Operator - Can't unlock phones (but sure as hell can lock them ).Service Center Std - Can't unlock phones.Service Center Rc - Can unlock phones, as they have a special version of the smartcard with a CSCA key.Research & Development - Can unlock phones, as they have a special version of the smartcard with a CSCA key.