1. CDMA Carrier Network Configurations
2. CDMA BASE_ID?
3. GSM Cell ID format

Answers

1. CDMA Carrier Network Configurations
   
   Below is a table of CDMA carriers in the telebeans coverage area and carriers encountered during out of area trips. There seems to be a correlation between the infrastructure vendor and some kind of default network configuration.
   
   

   Table 1-1: CDMA Carrier Network Configurations

   Carrier	Network	Vendor	NID	Base_ID Seperation	PN Seperation	PN Stepping	Comment(s)
   Alltel	Norfolk	Motorola	00026	1	4	12
   	Richmond		00011				ex CellularONE
   	SW VA		00020
   	Lynchburg/Charlottesville		00023	1	3	12
   	northeast NC/Greenville, NC		00002	1	6	18	SIDs: 01534 & 01544
   						3	SID: 01532
   CellularONE	Shenandoah Valley	?	00030	1	4	?	Virginia Cellular
   Cellular South	AL/MS Gulf Coast	Nortel	00005	1	6	?
   nTelos	Norfolk	Lucent	00031	256	168	6	ex PrimeCo
   	Richmond		00030
   	Staunton	Motorola	00013	1	4	12	ex CFW Intelos
   	Charlottesville		00014
   	Lynchburg		00015
   	Roanoke		00016
   	Bland Co. (N/O I-77 tunnel)/Beckley WV		00026
   Sprint PCS	Delaware/SE MD	Lucent	00000	256	168	?
   	Washington/Baltimore					3
   	Norfolk	Motorola	00130	1	4	12
   	Richmond		00080		random	random	originally setup like Norfolk
   	Shenandoah Valley	Lucent	00000	256	168	?	affiliate Shentel PCS
   	northeast NC/Greenville, NC		00000		24	4	affiliate AirGate PCS
   	MS Gulf Coast		00001		168	?	affiliate Gulf Coast Wireless
   	AL Gulf Coast						affiliate Louisiana Unwired
   U.S. Cellular	Charlottesville/Lynchburg/Roanoke	Nortel?	00000	256	168	4	ex Blue Ridge Cellular (C'ville)
   	northeast NC/Greenville, NC		00010	1	6	18
   Verizon Wireless	Delaware/SE MD	Motorola	00000	256	168	4	ex BAM
   	Washington/Baltimore				160
   	Shenandoah Valley	?	?		168	?	ex Shentel Mobile
   	Harrisonburg/Staunton		00000		172 (low to mid), 168 (mid to high)	4	ex CFW Wireless
   	Norfolk/Richmond	Lucent					ex GTE Mobilnet
   	Roanoke/Danville
   	AL/MS Gulf Coast				168	?	PCS only market
   	Atlanta (Hartsfield Airport area)	?	00004	1	4	12?	ex AirTouch Cellular

   
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2. CDMA BASE_ID?
   
   A BASE_ID is a CDMA parameter used to uniquely identify each sector on a tower. The closet analogy for the role of a BASE_ID is the GSM CID. However, the normal GSM CID decoding method is not applicable. Depending on the configuration the BASE_ID can be converted into a hexadecimal number, the first digit is droped and then the remaining two numbers are reconverted back to decimal. This will give the towers "CDMA tower number". In the case of AirGate PCS and Bell Atlantic Mobile (Verizon Wireless) this number is used in part of their cell site id signage. This information came via an exchange on the Howardforums website. Much credit to poster Life-is-Good for this very interesting conversion trick!
   
   However, this does not work for all carriers for some reason. CFW Intelos does not work. More research is pending.
   
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3. GSM Cell ID format

   A GSM Cell ID (CID) is a generally unique number used to identify each sector of a cell site within a LAC if not within a network. In many ways a GSM CID is similar in purpose to the CDMA BASE_ID paramteter (however decoding is radically different). For the carriers listed above the CID is actually composed of several different pieces of information in various schemes detailed below. Disclaimer: The information in Table 3-1 applies only to the carriers listed therein.

   Table 3-1: GSM Cell ID (CID) Formats

   Carrier	Scheme
   VoiceStream	LLNNS
   Omnipoint	LLNNS
   DigiPH PCS	LLNNS
   PowerTel	LLNNS
   AT&T Wireless (PCS)	NTTTS
   Triton PCS	NTTTS
   Tritel PCS	NTTTS
   BellSouth Mobility	NTTTS or TBD
   BellSouth Mobility DCS	NNNLS or LLNNS
   CellularONE (DC/Balt)	NTTTS
   Comcast CellularONE (DE/SE MD)	LLTTS
   Comcast Metrophone (SE NJ)	TBD

   Where:
   • N = CID numbers
   • T = TDMA DVCC (where appropriate, values range from 0 to 255)
   • L = Location or group
   • S = Sector ID (values 1 - 3 for each sector or 0 for omnidirectional)
   
   Overall American GSM providers used a NNNNS style of CID encoding similat to an older scheme used by Vodafone UK as opposed to a more complicated scheme such as the one used by Vodafone Australia. Carrier examples and exceptions follow below.
   
   Triton PCS: Triton PCS GSM CIDs incorporate a sites TDMA DVC, usually as the trailing digits of the CID. Triton PCS also uses incremental or padded CIDs to accomodate multiple DVCs. For one site will have a TDMA DVC of 15 and a corresponding CID of 15. However, the next sites that have DVCs of 15 will have CIDs like: 1015, 1415, 1815, 3315, 3415 (real examples). The first two digits happen to be some sort of prefix or location information. This works for three digital CIDs are well. A site with a DVC of 183 will have a CID of 1183. The only exceptions would be CIDs that end in 00. These usually have a DVC value that ends in DVC such as 200 (which has a CID of 1200). However, it is also common for a site with a DVC of 255 to have a CID that ends in 00.
   
   BellSouth Mobility DCS: With BellSouth Mobility DCS the CID contains the traditionally trailing sector id, a cell number and additional location information. However, the position of this location information varies depending on the LAC of the cell site. For example, cells in LAC 12241 (Rocky Mount area) the location information is the last digit of the CID. For example CIDs 17, 27, 37 are actually read as site #1, 2, 3 in location or area 7. However, in LAC 209 (Greenville area) the location information is the first two parts of the CID. For example cells 3207, 3219, 3226 are actually site #7, 19 and 26 in location/area 32.
   
   VoiceStream: CIDs are similar to the LAC 209 BellSout Mobility DCS configuration with the first two numbers representing some kind of location code or CID repetition indicator. However, CIDs with differing location prefixes can be in the same LAC. It is thought that the prefixes may refer to a localized grouping of cells around a BSC site. For example CIDs 5668 and 5660 may all backhaul or are controled by a BSC for group 56, i.e. CID 5601. This is all speculation.
   
   AT&T Wireless/CellularONE (DC/Balt): Ironicly both carriers use the same numbering scheme. Like Triton PCS, AT&T Wireless and CellularONE of Washington/Baltimore both have legacy TDMA systems to support and as such incorporate site TDMA DVCs into their GSM CID numbering scheme. However, unlike Triton PCS the DVC is used to create the GSM CID only once. For example if a site has a TDMA DVC of 18 the CID will be 18 (droping the sector ID). The next time a site with a TDMA DVC of 18 is found the GSM CID will be random and at this point in time have no connection to the TDMA DVC.
   
   CellularONE (Delaware): Sites in the Delaware (and SE MD) area have a two digital prefix always starting with 5. Since CellularONE in this region also ran a TDMA network CIDs sometimes incorporate the sites TDMA DVC value. However, this is not always the case. While a site with a DVC of 25 might have a CID of 5025, a site with 26 will have a CID of 5017! Prefix codes of 50, 52, 53 and 54 have been observed.
   
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