Roaming

The ‘home’ area for a wireless phone is the geographical area in which the provider has presence (towers, switches, etc). Once a wireless subscriber travels outside his home area he is considered to be “roaming.” In order for the subscriber to make calls in another carrier’s home area, the two wireless carriers must have set up a roaming agreement between themselves. If no roaming agreement exists for a call, that call cannot be rated.

A CDMA/TDMA wireless provider’s geographic area is identified by one or more SIDs. (A SID is a System ID, a 5-digit number that identifies a geographical portion of a particular provider's network.) Every wireless call record contains a ‘serving SID’ which designates what part of which carrier’s network handled the call. The list of SIDs and their associated line ranges are managed by Syniverse. IDI must provide a means of importing monthly updates from Syniverse to keep its SID information current.

For GSM calls, the geographic area is identified by a PMN (Public Land Mobile Network). PMNs and their roaming usage are also managed by Syniverse.

All wireless calls must end up in the wireless carrier’s usage outcollect database so that subscribers may be properly billed for those calls. To accomplish this, wireless CDRs (call detail records) are traded in a specific format.

Records for CDMA/TDMA wireless calls are in CIBER format (Cellular InterCarrier Billing Exchange Roamer).
Records for GSM wireless calls are in TAP 3.11 format (Transferred Account Procedure), defined by the GSM Association.
An ARP (Authorized Receipt Point or clearinghouse, such as Syniverse) is used to send CIBER and TAP records from the serving carrier to the home carrier.
To the home carrier, a batch of incoming CIBER/TAP records is called an Incollect.
From the serving carrier’s perspective, it is called an Outcollect. IDI provides the ability to process Incollects, create Outcollects, and provide error handling on the files as they travel to and from the home carrier’s partners via the ARP.