 |
|
|
Billing in real time ... billing in gory detail ... billing for enhanced services ... billing wireless data transmissions ... traffic statistics ... customer care statistics ... marketing information ... fraud monitoring. If I promised you a standard with all those capabilities, wouldn’t you leap at the opportunity to use it? Yet, such a standard exists and carriers have been extraordinarily slow to adopt it. TIA interim-standard IS–124 was first published in 1993, yet moving into its third revision, its future is still unclear. Is it the future of wireless billing or just the “big standard that couldn’t”?
Real-time billing is desirable for a number of reasons. New services are made possible, or at least more efficient and leak-proof, through real-time billing, including prepaid calling, calling party pays, rental phones and providing call charge information to wireless subscribers. Perhaps more important, however, is reducing the time between when a call is made and when it appears on a customer bill. During this whole time, either the serving carrier or the home carrier is, in effect, financing the caller. The sooner a billing record can be delivered from the carrier that served the roamer to the home carrier, the sooner the serving carrier receives payment. And the sooner the home carrier receives the record, the sooner it can put it on a customer bill and get paid for it. Furthermore, the longer the delay between making a call and receiving a bill, the more likely callers are to forget that they even made the call and challenge the charge, which costs the carrier both money and time (which, after all, is also money).
Billing standards are required in wireless largely because of roamers. When someone else’s customers can access your system, you have to have some way to get information back to their home system so that you do not have to bill them directly. Furthermore, enough information has to be collected to ensure that the home carrier sends your portion of the roaming revenue they collect back to you (the process known as “settlement”). Currently the dominant billing standard is the CIBER record which is fundamentally a magnetic tape format, although it is also transferred over networks as well. CIBER formats date back to a simpler era, when all record structures were fixed in length and all data was in text format. COBOL programmers would be very comfortable with CIBER. The record content is focussed entirely on billing, and the records only coincidentally contain information that can be used for other purposes (e.g. fraud management or customer care).
IS–124 (soon to be renamed as ANSI standard TIA/EIA–124 Revision B) is, by contrast, a very modern standard. All information is in hierarchical format, with variable-length records and fields containing a large variety of binary encoded information – some mandatory and some optional. SQL database programmers would be much more comfortable with IS–124 than with CIBER.
Because of this flexibility, IS–124 records can be customized to satisfy one purpose, or for a number of simultaneous purposes. All this flexibility comes at a price, however. Information cannot be recognized simply by its position in a rigidly structured record, but each piece of information must be identified, and the pieces of the hierarchical list of sub-records must be linked together, often in both directions. This makes the records significantly larger, increases network throughput requirements, multiplies computer processing requirements and (perhaps most importantly) increases the cost and complexity of software development.
The flexibility of IS–124 also introduces a compatibility problem. Unless the entire standard is implemented, which would result in whale-sized records, with a similar proportion of fat, it is necessary to develop agreed subsets of IS–124 for different applications. Cibernet Corporation initiated industry meetings for this purpose. First came NSDPF (Non-Signaling Data Protocol for Fraud) that allowed the exchange of call detail records in IS–124 format for post-call fraud monitoring. While authentication has removed the usefulness of some IS–124 based fraud applications, burgeoning interest in subscription fraud has made other applications even more critical.
Following NSDPF, the Cibernet-led group initiated the development of NSDPB&S (Non-Signaling Data Protocol for Billing and Settlement). This recently completed effort was actually more than the development of a subset. It identified some weaknesses in Revision 0 of IS–124, and corrections became an important input to the development of Revision A by TIA standards subcommittee TR–45.2. Further corrections to IS–124 are being incorporated in TIA/EIA–124 Revision B, which is currently in the ballot process. Major players in this process include Metapath (editor for IS–124 Rev. A), Systems/Link (editor for TIA/EIA–124 Rev. B), EDS (source of many technical corrections), Ericsson and consultant John Willse (chairman of TIA TR–45.2 Working Group IV). Originally, McCaw (now AT&T Wireless Services) and Synacom contributed significantly to the development of Revision 0.
One more hurdle to the implementation of IS–124 is the lack of a single, standardized transport protocol. Although many telecommunications interfaces allow multiple transport protocols (PSTN interconnection and IS–41 being two examples), there generally is a single lowest common denominator. PSTN interconnection, for example, uses MF tones as the basic transport protocol and IS–41 used X.25 level 2. This allows a transition to a protocol with greater performance and capabilities (which, for both PSTN interconnect and IS–41 is SS7), without losing compatibility with older systems. CIBER records used 9-track magnetic tape as the original transport medium, and have since migrated to other tape formats and even electronic file-transfer of records. However, there are certainly no billing houses that would not still accept 9-track tapes today. Without a single basic standard transport protocol, IS–124 implementors are forced to develop agreements ahead of time to ensure compatibility. Should it be TCP/IP, Frame Relay or ATM? This is especially difficult for prospective vendors of equipment, that do not know which network protocols they should use for design and fabrication.
Real-time billing and faster settlement processing will eventually herd the industry toward implementation of IS–124, but it will still take some time, as the online exchange of CIBER records is a viable option today. While CIBER is much less flexible, it is available today, and is more compatible with much of the existing billing infrastructure. Gradually, as all the pieces come together, as IS–124 equipment and services become available, and as the demands for real-time billing increase, carriers will commit to IS–124. A recent NACN trial-run involving EDS, Metapath and Vertel has, according to Peter Larsen of Metapath, shown that the pieces of the puzzle can be put together, although there is more that needs to happen before it can be used in fully commercial applications. Ironically, a growing interest exists in Europe regarding IS–124, as it is compatible with GSM and provides considerably more flexibility than GSM’s current TAP billing standard.
© Copyright