CALLER ID and ANI PRIMER Published in CTI MAGAZINE FEB '97 VOL. 2 NO. 2 Page 52

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INBOUND SYNCHRONIZED SCREEN POPS: CALLER ID and ANI PRIMER

Caller ID and Automatic Number Identification (ANI) -- the public switched network services that support synchronized screen pops -- are creating a revolution in the way that computers and phones are used together. Because CALLER ID and ANI are often confused, an understanding of how these services work and the differences between them (See Table) will help you avoid problems and prevent unrealistic performance expectations in your CTI implementations.

THE DIFFERENCES

In North America both services generally provide a 10-digit identifying number. In the case of Caller ID, the 10 digits constitute the actual trunk number from which the call originates. ANI delivers the pilot or billing telephone number (BTN) of the caller. CALLER ID is provided as a Bell 202 modem signal between the first and second ring of the call on an analog line: therefore, if the call is answered before the second ring the identifying signal is lost.

CALLER ID is available on Loop Start trunks only. CALLER ID is not available on ground start, or DID (Direct Inward Dial) wink start trunks, or choke networks used by radio and television stations. ANI is provided before the first ring on a digital T1 or PRI in a DTMF or MF, or inband signaling protocol.

CALLER ID is sold to the end user by the Local Exchange Company (LEC). ANI is sold to the end user by the Interexchange Carrier (IXC). CALLER ID is generally sold as a flat-rate monthly feature. ANI is sold on a per call basis.

Currently, only the number is delivered in many areas of the United States. Most areas served by Bell South, some areas served by US West, BellAtlantic, and Ameritech are now offering name delivery capability. Check with your Local Telephone Company to see if they offer this service. It may cost more that the number only service.

CALLER ID can be blocked. ANI cannot be blocked. CALLER ID is not always delivered on all calls. ANI is always delivered. CALLER ID has more variations of the information, including name or dialable number.

SCALE OF IMPLEMENTATION

The first questions asked of any potential customer pertain to size issues. How many lines does the customer anticipate using? How many computer nodes? Traditionally, ANI implementation on a large call center environment will cost over $100,000. Obviously, the T1 circuit that provides the ANI is a small portion of this price tag. This figure is usually only a starting point and can go up dramatically in a mainframe-type installation. CALLER ID implementations should generally cost about $200 per computer for the hardware and software in the PC DOS or Windows arena.

ORIGIN OF CALLS -- LOCAL or LONG DISTANCE

Futhermore, it must be determined if the calls that need to identified are incoming from the local calling area or are originating as long-distance toll calls. Since CALLER ID started out only delivering local calls, early screen pop applications were limited to customers with local residential to business calling patterns (Pizza delivery, pest control, fuel oil delivery, taxi dispatch and the like). If you plan to use CALLER ID in a business to business situation, a database architecture that supports a many-to-one relation will be needed to allow a company's multiple telephone numbers to recall the same contact record. This may also be true if the calls originate from multiple locations, such as work, home, or cellular. The local scope of CALLER ID has recently been expanded to provide nationwide numbers, whereas ANI has been delivering numbers from all over the country since the early 1980's.

TOLL-FREE VOLUME

Next, it is important to ask any potential customer whether calls are already coming in on a toll free number. If the calls are coming in on a toll-free number, what volume of is the customer using? Will the volume Justify a T1? Are they or should they be using switched or dedicated toll-free? Who is or will be the carrier for this traffic? ANI is delivered by all the major carriers. CALLER ID is, as of July 1997 is reliably delivered by all major carriers except LDDS WORLDCOM and its siblings. Obviously, WORLDCOM, and its subsideries need to be avoided when using CALLER ID in your switched toll-free. If the incoming calls are not toll-free, then CALLER ID is your only choice. If CALLER ID is being used, what calls will have their ID blocked and what calls will be tagged as out of area or private.

BLOCKING CALLS

With CALLER ID, the caller can press *67 prior to placing the call (per call block) and the receiving end will see a private indication. In about half the states you can request that the phone company automatically block your number on all outgoing calls. (SEE CALLER ID MAP) Californians are particularly fond of this feature, with over 50 percent of lines being automatically blocked in some areas. Blocking will have no effect on 800, 888, or 900 dedicated circuit calls. California redidents are just learning about a feature named Anonymous Call Rejection (ACR), which is now available in many states east of the Mississippi. ACR allows the recipient of a private call to have a central office generated message played to the caller, refusing the call without even having to hear the phone ring. In order for a line subscribed caller to get through to an ACR line, the caller must press *82 to per-call-unblock their number. So, if a large percentage of your calls are placed to California, get an 800 number on a T1, and blocking will cease to be an issue.

OUT OF AREA RESTRICTIONS

Out of Area indications occur when some part of the Signaling System 7 channel does not complete the delivery of calling party number in the IAM (Initial Address Message) setup message of a long distance call. (Refer to BELLCORE for a complete 500 page technical specification of how this works.) This can be caused by a number of ailments and requires a real communcations guru to point the accusing finger at the actual offender(s). Suffice it to say that Out of Area calls are still occurring in many long-distance CALLER ID calls (20 to 40 percent) depending upon the carrier that is being utilized by the caller. Analog cellular calls also will deliver Out of Area indications, while newer digital cellular cals generally give up their number. Be careful of these calls in any CALLER ID implementation.

CONSIDERING GROWTH?

Not all phone key systems or PBX's will accommodate CALLER ID and/or ANI, especially when it comes to computer-telephony integration (CTI). You have to be careful to select a phone system that not only can receive the signals, but hand them off to a computer system in a useful manner. Growth is the watchword here. Will you start out with local loops and grow into a T1 or beyond, requiring both CALLER ID and ANI? This issue will most certainly require some professional assistance.

DISTRIBUTION AND SERVICE

Unfortunately, there only a handful of true professioanls who understand the public switched network features, the customer premises equipment, and the computer network and software critical to implementing a workable integration. Since there is currently no defined channel for distribution, we sometimes find the interconnect as the seller and sometimes the VAR. Even the local phone company may get involved. So who does one contact for these products? Many CTI Vendors are now orchestrating some sort of cooperation between interconnects and VAR's in order to more competently service their customers. Many VAR's that regularly deal with software interconnection issues are at a loss when dealing with the complexities of third party call control in a TSAPI environment or first-party call control in a TAPI implementation. The providor's connection model affects the SPI and/or API feature levels available. Both TSAPI and TAPI have their strengths and weaknesses. To further complicate things, much hype exists about CSTA, TAPI, TSAPI, SCSA, MVIP, and several other emerging standards. And still, many phone system vendors have yet to embrace any standards at all.

CONCLUSION

These are just some of the potential pitfalls of CALLER ID and ANI. There is a level of detail in any CTI installation that most vendors have not experienced. But, as always, this presents opportunities for those willing to apply tourniquets to the bleeding edge.

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