Difference between revisions of "Public:CDMA"
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====System Identification conflict with GSM MNC==== | ====System Identification conflict with GSM MNC==== | ||
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| − | Some SIDs exist with an exact same MNC code for a GSM network in the same country.<br> | + | |Some SIDs exist with an exact same MNC code for a GSM network in the same country.<br> |
[[File:Identical_sid_and_mnc.png]]<br> | [[File:Identical_sid_and_mnc.png]]<br> | ||
In order to differentiate between these two network types it is important that each client contributing data to the OpenCellID database provides an information on which network this data has been collected. Details can be found [[API#Payload|here]]. | In order to differentiate between these two network types it is important that each client contributing data to the OpenCellID database provides an information on which network this data has been collected. Details can be found [[API#Payload|here]]. | ||
Some information regarding SIDs is also provided on [http://en.wikipedia.org/wiki/System_Identification_Number Wikipedia]. | Some information regarding SIDs is also provided on [http://en.wikipedia.org/wiki/System_Identification_Number Wikipedia]. | ||
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=== (NID)=== | === (NID)=== | ||
Revision as of 01:34, 9 February 2014
ContentsCDMA informationGeneralCDMA networks exist in parallel to GSM networks. Details can be found here The CDMA networks existing in January 2014 are listed in this document. Latest information for each county can be found here at ifast. Here you can find out for a given network to which country it is allocated. Here you can find out the carriee for a given SID. A CDMA cell tower identification consits fo the following information:
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System Identification (SID)
| The SID (System Identification Number) is a 15 bit number (0-32,767) transmitted by base stations that identifies a wireless system that conforms to a TIA cellular or PCS standard. The SID is used by mobiles to recognize when they are in their home system (e.g. it controls the "roam" light). Some newer phones may maintain a list of "preferred" systems identified by their SID code. The SID may also modify some signaling messages that are transmitted by mobiles.
In the wireless network, the SID is used for billing purposes, as a unique identification of the system that is serving a mobile (and that thus must be compensated for services provided to roamers). Since it is easier to transmit a 16 bit number on a network, a new range of SID's are available for network purposes only (32,768-65,535). Some of these are used as BIDs (Billing Identifiers), and are used to discriminate between different portions of a system for accounting purposes. BIDs are assigned by CIBERNET (+1-202-785-0081). SID codes are assigned by the national telecom regulator, a designated organization or, failing that, by IFAST if the national authority is unwilling or unable to perform this task or if the operator wants a range directly from IFAST (e.g. a mobile satellite operator). If a country does not have a SID range, or needs a larger range, they can apply to the IFAST to have one of the reserved ranges listed below allocated. Not every country that has been assigned a SID range is actually using it (for example, GSM and NMT systems do not use the SID identifier). IFAST has been allocating SID ranges since November 1997. Prior to that, SID ranges were allocated by TIA subcommittee TR-45.2. |
System Identification Number Allocation
| ifast is the organization responsible for the allocation of ranges of SIDs to each CDMA network provider world wide.
These SIDs are world wide unique, so NO (!) MNC or MCC information is needed for identifying each network. Some networks transmit in addition to the SID an MCC and/or MNC number. The OpenCellID backend ignores this information because it is not clearly specified and if present, then redundant. |
System Identification conflict with GSM MNC
| Some SIDs exist with an exact same MNC code for a GSM network in the same country.
Some information regarding SIDs is also provided on Wikipedia. |
(NID)
In a CDMA network, a mobile station judges whether roaming takes place based on a pair of identity numbers (SID and NID). System Identity Number (SID) includes 15 bits. Each local mobile network is allocated with one SID and the specific number allocated to each local network is specified by the network provider. Network Identity Number is made up of 16 bits, with 0 and 65535 reserved. 0 is used to represent those base stations in a certain SID area not belonging to a specific NID area. 65535 is used to indicate that a mobile user can roam in the whole SID area. For a CDMA network side, there is no concept of NID, but an exchange number (one byte), which is used to identify the network equipment where a user is located.
(BID)
CDMA terminology
Further CDMA related terminology can be found here.
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