Standards Watch: Improving Interconnect Between Wireless and Wireline Carriers

If recent inter-carrier disputes and lawsuits, as well as the troubles around the universal service fund are any indication, the traditional parameters for determining routing, call rates, and inter- and intra-state access rates are no longer sufficient for inter-carrier compensation. An accurate account of where calls originate and terminate are necessary because of the complexity of local, state and federal jurisdictions' rates and taxes.

"I spend a lot of time exchanging data, arguing and working out agreements because we increasingly have wireless affiliates with which to settle, and we cannot decipher the physical location of the wireless caller," says James B. Elgin, director of new switching products, SBC. As the person in charge of developing new products used by CLECs and VoIP ISPs, Elgin knows well the trials associated with inter-carrier compensation as well as the complaints on the wholesale side around wireless roaming. "Because wireless carriers sometimes get discounts on interstate access rates on originating calls if, they don't mind if calls are ‘misjurisdictionalized.'"

That fact may serve as an incentive for some operators to drag their feet in resolving roaming issues in inter-carrier disputes, if they know a resolution would invoke a higher interstate access rate.

Not only do carriers waste a lot of time arguing and lose potential revenue, but they also risk frustrating customers who are inaccurately blocked from toll-free zones when geographic location is misconstrued.

Originating call resolution

To answer to issues around call origination, a two-year effort carried out by ATIS' Network Interconnection Interoperability Forum (NIIF) last month yielded procedures for getting accurate geographic information for call origination into SS7 initial address messages (IAM).

Wireless and wireline operators, equipment vendors and other forums such as T1S1, OBF, TR-45 coordinated to implement existing Jurisdiction Information Parameter (JIP), a six-digit field to populate SS7 IAMs. Today, JIP is an optional parameter to convey geographic information about the location of the calling party, and the NIIF recommends seven rules for populating JIP.

"The hope is that the population of JIP data becomes commonplace for both wireline and wireless carriers, where technically feasible," says Stu Goldman, chair of the NIIF. "Carriers can mitigate the amount of revenue they lose if they can better determine the actual location of the caller, thus enabling more accurate routing through interLATA and intraLATA trunks, as well as procure more accurate information for taxes, and billing."

Currently, the originating wireless carrier can send a JIP when a call is initiated, and know where the person is located and when the call terminates. And the terminating carrier can see from what location the JIP came.

"If I'm a New Yorker in a Florida hotel, my cell phone number indicates what carrier I'm using, and the extra six digits in JIP will indicate the area in which I'm calling—such as Clearwater Beach, Florida," explains Goldman. "Having that extra information improves the routing of the call, and reduces the chance of the caller experiencing adverse feature interactions, such as loss of access to toll-free calls."

Callers blocked from making banded toll-free calls that are supposed to be allowed under their subscriptions will become frustrated and possibly churn. Conversely, carriers eat the cost of enabling access to banded toll-free areas to which the caller should be barred.

Terminating call resolution

The problem currently is that JIP answers to only half the equation. If the call is initiated from a wireline phone and terminates with a wireless phone, it is difficult to know in what city the call termination takes place, because that JIP field has not yet been addressed. In other words, an interstate call under federal jurisdiction could cause disputes, because it's difficult for the terminating carrier to determine in what city the caller really was. For wireless carriers that receive a discount based on the originating JIP, there is the opportunity to get charged a higher interstate access rate with the terminating JIP than they are currently accustomed to.

To make it a bi-directional standard, the NIIF committee is working on NIIF issue 233, which is supposed to bring JIP full circle. "If the industry is to embrace the use of jurisdiction rather than phone numbers in inter-carrier compensation, it has to be equally applied to all carriers on all sides—with both an originating JIP and a terminating JIP," says Elgin. "Some wireless carriers contend it would be a tremendous change to have to send additional data on the terminating side, because they don't normally have to do so when receiving a call. However, data is sent about trunk set-up through signaling messages, so that should not be too great an obstacle for wireless carriers to overcome."

Addressing VoIP

As carriers evolve from LNP to number portability outside of the rate center, the problems will worsen if physical location is not known, especially now that VoIP and next generation services are coming to fruition.

The NIIF's issue 246 is JIP for VoIP. "In VoIP, any number is given to anyone. A small business owner who wants an international flair could get Paris number, even if he's located in Indiana. That will really confuse jurisdictional matters if location is not known," says Elgin.

The NIIF is setting out to define what VoIP traffic is, and then look at whether the FCC will treat it differently or the same as regular traffic. "Carriers don't want to have to isolate that traffic if the FCC is going to treat it all the same. If they don't, we then have to figure out how to distinguish it through rules and definitions that are IP-specific," adds Elgin.

The hope is that VoIP JIP will populate information to ensure rating, routing and blocking are accurate with IP telephony," says Elgin.