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CPSR, October 8th, 1992

CPSR, October 8th, 1992





UM 365

UT 115


In the Matter of an Investigation into CALLER ID and other Custom Local Area Signalling Services (CLASS).


In the Matter of Revised Tariffs filed by U S West Communications, Inc to implement Caller ID and other Custom Local Area Signalling Services in Oregon. (Advice No. 1478 and Transmittal No. 3846)


Comments prepared by Computer Professionals for Social Responsibility (CPSR) member

Carl Page

710 SE 73

Portland OR 97215






Summary 2 UM 365 Reconsideration Issues.

1 Free Line Blocking, or an $8.00 Fee Increase? 3

2 Line Blocking Deactivation with a Unique Code (LBDUC). 4

2.2 Should the requirement for LBDUC be relaxed? 5

2.3 On the Need for Line Blocking Deactivation (LBD) 5

2.4 On the Need for a Unique Code for Line Blocking Deactivation 6

2.5 On the Need for Anonymous Call Rejection (ACR) 6

3 Last Call Return (LCR) Blocking. 7

UT 115 Issues

4 Call Trace Price. 7

5 Liability Limit for Blocking. 7

6 Consumer Education Program. 8

6.1 Who must receive the basic information packet? 8

6.2 What set of points must the basic information packet cover? 9

6.3 A Minimal Basic Information Document 9

7 Selective Call Rejection (SCR) Price. 11

On the Balancing Act 11

On Software Changes 12

Certificate of Service. 12


The introduction of the CLASS services can enhance or detract from Oregon citizens security and the peacefulness of their homes. The Calling Number Identification service (CNID) can complicate the ability to make anonymous calls which is occasionally essential.

US West's tariff does not meet the requirements of the Commissions order, nor does it satisfy the principles that directed the design of the order.

Most of the issues revolve around who controls the distribution of a person's number. Unlisted number customers who attempt to maintain the confidentiality of their numbers would be put in a hopeless situation by US West's proposed system.

"Line blocking" is now free and should remain that way.

Reliable Line Blocking Deactivation (LBD) is needed independently of whether Anonymous Call Rejection (ACR) is available. LBD can and should be implemented with a unique code, as described in the Order.

Last Call Return (LCR) is a marginally useful convenience that is not valuable enough to outweigh the dangerous privacy problems that would be created if it were capable of returning a blocked call. The introduction of LCR should be delayed until it works safely which is scheduled to be within two years. If LCR were implemented in its current form, the financial motivation the private, unregulated switch vendors have to provide safe service will evaporate and the changes would be far less likely to be made on schedule.

$1.00 is a reasonable price for Call Trace regardless of the incremental cost of providing the service.

No liabilty limitations for call-blocking failure should be provided unless it can be shown to be clearly in the public interest.

No information on the required Consumer Education program was supplied in the Tariff, yet the unnecessary complexity created by the US West's proposed design creates real doubts that the system can be explained adequately in a reasonable number of words.

Selective Call Rejection (SCR) is a solitude enhancing service which is priced above its utility but deserves to be widely available.

Weakening CLASS services in the manner US West proposes would transform a marginally useful service into one that is detrimental.


1 Free Line Blocking, or an $8.00 Fee Increase?

The $8.00 charge for establishing a new line with todays standard level of service is a dramatic departure from the principle established in the PUC's order which provided for the continuation of existing service without additional charges. The 90 day delay in instituting the charge is irrelevant in the long term. "Line blocking" is a new name for the status quo, not a new service. The new service is the state of not having line blocking, which should be know as "Automatic Calling Number Transmission" (ACNT). Establishing a new charge for "Line Blocking" is a general rate increase to the cost of establishing service, and no justification has been provided that would explain why such an increase is necessary.

The charge is unfair because it is the purchasers of information who should pay for its distribution. The subjects of a form of electronic surveillance should not have to make protection payments to keep their data private.

US West warns of the danger of the popularity of line blocking diminishing the value of the CNID service. Ironically, CNID's value to citizens is marginal compared to the value of a service it undermines, the unlisted number service. In reality this is just an additional $8.00 fee that all people who wish to preserve the confidentiality of unlisted numbers will have to pay when obtaining new lines.

The following quote, by James Cartini in the May 1991 "Industry Forum" column of Telecommunications illustrates how some telecommunications industry insiders view the issue.

"Maybe Caller ID should have been quietly been put into place as an overall network upgrade and Call Blocking should have become the hot new residential feature. Then, if customers still wanted to preserve confidentiality, they would have to subscribe to Call Blocking at $6.50 a month. Call blocking would then be the new residential revenue generator pinpointing a quick 25-30 percent residential penetration that the operating companies were looking for, not Caller ID.

Does this sound far fetched? Not when you take a look at the amount of people who already pay for an unlisted number. In metropolitan Chicago alone, about one third of the subscriber do not want their phone numbers published. (In Los Angeles, this number approaches 50 percent), They will pay for anonymity and confidentiality."

Since the number of people who choose unlisted numbers is large compared to the number of people who will choose CNID, it is possible that an $8.00 fee for line blocking would produce more revenue than the CNID service itself.

Peace and quiet in the home is a fundamental need that everyone shares. The affluent will have it through CPE. In this day and age there is no such thing as a nominal charge. An extra $8.00 charge on top of all the other charges for establishing service will make it impossible for many financially strapped families to get the service they need.

There is a fair way to encourage people not to block calls. If sales of numbers to CNID customers is really so lucrative, why not share the proceeds with the possessor of the number? Instead of establishing a fee for blocking, a discount for not-blocking based on proceeds from the sale of the CNID service would provide customers a fair economic incentive to avoid call blocking.

Line Blocking Deactivation with a Unique Code (LBDUC).

2.1 Is It Feasible to Provide LBDUC

It is feasible to offer Line Blocking Deactivation with a Unique Code (LBDUC). There does seem to be a problem with providing for the CNID customer the most extensive service possible while providing LBDUC. However, CNID and LBDUC can be provided together now in a manner that meets the requirements of the Commissions order, if not US West's current marketing plan.

We will provide a detailed statement of the technical feasibility in our reply comments which are to be released by October 22.

2.2 Should the requirement for LBDUC be relaxed?

There are really three separate issues here combined into one confusing morass, which obscures the policy questions surrounding each issue. These three issues are:

Whether to provide Line Blocking Deactivation (LBD)

Whether to provide Line Blocking Deactivation with a Unique Code. (LBDUC)

Whether to provide Anonymous Call Rejection (ACR).

Fortunately, it isn't necessary to tangle these issues together. Contrary to US West's claims, all of these services are valuable in their own right when considered separately.

2.3 On the Need for Line Blocking Deactivation (LBD)

There are many important reasons why a caller might want to temporarily unblock a blocked line. They may be calling someone with CNID (Calling Number Identification) who chooses not to answer blocked calls, or who has Customer Provided Equipment that provides the function of ACR. The caller may choose to unblock some calls for efficiency's sake, to allow a bank teller instant access to their account, for example, or to protect the safety of the called party, such as when ordering pizza. The caller may wish to take advantage of an associates "Distinctive Ring or VIP service". The caller may need to access a high security information service which only accepts calls from registered users calling from prearranged numbers. Pizza delivery companies should be able to insist that people order from unblocked phones, and their customers should be able to comply, even those with line blocking. (Pizza businesses would avoid ACR because they want to accept calls from blocked lines, so they can explain the need to unblock before ordering.)

Per-call blocking is not the answer for this customer if they need to protect the confidentiality of an unlisted number, because that services human-interface design guarantees that the number will quickly be exposed.

In light of the multiplicity of important reasons for LBD, it is clear that US West's novel claim that ACR is the dominant reason for LBD is absurd. It is worth mentioning that Bellcore's original design for the CLASS services includes line blocking deactivation without any mention of ACR. Tieing the importance of Line Blocking Deactivation to the presence of ACR trivializes the many reasons people need that service.

Customer Premises Equipment cannot be relyed upon to provide reliable per-line blocking that can be switched on and off. Not all such devices have a convenient on/off switch. Once such equipment is installed, temporarily unblocking the phone for a call could require rewiring the junction box. These cheap CPE devices could also silently fail to block calls, they may be incompatible with other CPE devices, and they are unduly difficult to install in a household. In most apartment buildings the telephone junction boxes are inaccessible to residents, which can make the installation of apartment wide CPE devices impossible. CPE blocking is an undue burden on phone subscribers.

Line Blocking Deactivation with a Unique Code is essential and should be offered as soon as CNID is available. Failure to provide a reasonable method of temporarily unblocking a blocked line will seriously inconvenience customers who choose line blocking. Crippling the line-blocking option in this way would have the effect of discouraging the use of line blocking, contrary to the aims of the order.


2.4 On the Need for a Unique Code for Line Blocking Deactivation.

During the Commission's hearings, there was general agreement that Bellcore's original design, which uses *67 for both blocking an unblocked line, and unblocking a blocked line, is too error prone for users who are not sure whether the line they are on is blocked or unblocked. A reliable way to block a call on an unfamiliar phone is essential, and one straightforward way would be to use a different code for unblocking than is used for blocking.

US West has already assigned a number of *NN codes, and they admit that there are two still available. We only need one. One of the two available codes should be assigned, or one of the codes U S West has assigned beyond the Bellcore standard should be reassigned. U S West's assignment of codes beyond the Bellcore standard, with apparently little communication with Bellcore, is risky. Better coordination between US West and Bellcore is clearly called for on this issue. US West should consult with Bellcore and come back with a better-coordinated proposal. Allowing CNID in Oregon without LBDUC would eliminate the only serious financial motivation that US West and Bellcore have to provide it.

2.5 On the Need for Anonymous Call Rejection (ACR)

The ACR service is one of the best ways to utilize the CNID system to actually obtain a reduction in the number of unidentified callers to the household, and therefore a respectable increase in perceived solitude. It should be made available as soon as possible.

As described in the Order, ACR, LBDUC, and CNID provide a set of negotiating tools. Without any of these tools, the negotiation will have reduced effectiveness, but denying any of these tools will preclude effective negotiation.

3 Last Call Return (LCR) Blocking.

Because it is inconvenient for US West to provide blocking of LCR, they propose to offer LCR that returns all calls, even blocked ones. No compromise can be made on this important safety issue. The LCR service should not be offered if it violates the commitment to effective call blocking.

It is important to keep in mind the fact that the LCR service is not a critical one. Returning calls to people who want their calls returned is rarely a problem. When it is, LCR still cannot be relyed upon, because another call can always come in which will wipe out the number that had been saved as the last call. Unlike CNID, LCR cannot return the second-to-last call.

The costs vs. the benefits of offering the LCR service have to be compared carefully. If the LCR service will cause the utility to violate the expressed commitment that offering call blocking represents, then that cost clearly outweighs the benefits of LCR.

We do have evidence provided by US West that customers have already felt betrayed when their blocked calls are available to the called party for dialing. It is surprising that this problem has been detected in service already. It will get worse as time goes on in the states that already have the defect in call blocking created by the LCR service.

Last Call Return of a blocked number is a hazardous trap to set, like leaving off manhole covers. Just because disasters would happen infrequently doesn't mean that it is responsible to knowingly set them up.

4 Call Trace Price.

The new call trace service should be offered at the nominal charge of $1.00 regardless of the incremental cost of providing the service.

5 Liability Limit for Blocking.

US West has not provided one shred of evidence to explain the need for their request for a limit of liability for damages resulting from the failure of call-blocking. The limit they suggest is the cost of blocking, which of course is free.

It is in the public interest for the telephone companies to obtain insurance against this remote possibility. This would allow citizens (or estates) who are injured by blocking failure to recover real damages, without threatening the viability of the teleco. If a court found that the teleco did not display due diligence in attempting to make call-blocking work, they might also be subject to punitive damages, but that too is as it should be.

This request for total immunity from well grounded lawsuits by injured citizens betrays an un-American distrust of our extensive and world renowned legal tradition. The technology exists to make call-blocking work, but will the motivation still be there if the telecos are officially declared irresponsible for their actions?

Since the technology exists to make Call Blocking work, the concern over lawsuits seems strange. Unless US West can show that they have been subjected to an expensive flurry of groundless lawsuits in the states where CNID trials have been conducted, there is no reason at all to grant their request for a liability exemption at this time.

6 Consumer Education Program.

The US West Tariff is incomplete because it does not describe in sufficient detail the consumer education program. While it would be fortunate if we could trust the telecos to do a reasonable job describing the new services and their implications, experience with telecos such as BellSouth in other states has shown that they will circulate the minimal amount of information to the minimal number of customers in a way which emphasizes the positive effects of the changes and downplays the negatives. Such a biased treatment endangers customers.

6.1 Who must receive the basic information packet?

There are a number of things that every customer must know in the CLASS environment as proposed by US West to protect their personal safety and the safety of others. All of these points must be made to every customer in every area where outgoing calls may be received by a CNID equipped phone. This includes those who speak languages besides English, and Oregon's non-readers who number around 600,000.

The information must be distributed to all customers upon introduction of the service in any area where the customer may have their number transmitted to another customer who has the CNID or LCR service. It doesn't matter if the customers exchange can support that customer purchasing CNID, only whether it is ready to pass the customers number on to others that have the service.

The information must be distributed to all customers who establish new service in a household who may have moved in from an area where CLASS services are not available, or who may be establishing their first household and have not had the opportunity to make these decisions before.

6.2 What set of points must the basic information packet cover?

Note that most of the verbiage in this minimal instruction set explains "bugs" and problems with the system that could trap the unwary. Many of the most difficult to explain problems need be explained only if US West's proposed tariff is accepted. This explanation would be far shorter and simpler if the Commissions order were implemented correctly without revision.


6.3 A Minimal Basic Information Document

How to make an anonymous call.

o You can always use operator assistance if you don't feel you understand how to use the automatic codes described below. Obviously when using operator assistance, the operator will know you are making an anonymous call but they are obligated to keep such information confidential.

o Use operator assistance if you do not wish the called party to call you back using Last Call Return.

o Use line blocking. You can obtain line blocking by calling customer service. Note that line blocking may not prevent customers with Last Call Return from returning a call and learning your location or identity based upon who answers or by observing your number on their phone bill. Teleco does not guarantee that Line blocking will be effective and is not legally liable for any damages resulting from its failure.

o If you do not have per-line blocking dial *76 to use per-call blocking. Note that it may not prevent customers with Last Call Return from returning a call and learning your location or identity based upon who answers or by observing your number on their phone bill. Teleco does not guarantee that per-call blocking will be effective and is not legally liable for any damages resulting from its failure.

o Even if you take the above actions and make an anonymous call, the called party can still use the new call trace service to make your identity available to the teleco's nuisance bureau and law enforcement authorities. If the called party claims that your call is abusive or threatening, these organizations will investigate the matter, but they will not routinely give your identity or number to the called party.

o Use operator assistance to call numbers with 800 area codes because they may receive your number regardless of your blocking choice.

o Do not call numbers with 900 or 524 area codes because they will receive your number regardless of your blocking choice.


Making an unblocked call.

o Note that when the called party has Caller-ID they may get your name or number. The name and number may be used to look up records about you in a database before they decide whether to answer your call. It is illegal for lending organizations to use such information to discriminate against prospective customers, but few other businesses are so regulated.

o If you call from someone else's telephone line, there is no way to substitute your own identity.

How to interpret the information on your Caller-ID display.

o The name displayed on a caller-ID device is merely the billing name for that line, not necessarily the person who is calling you.

o Elaborate equipment can fabricate false caller-ID signals, and random transmission errors occasionally will effect the displayed number. Therefore a number on a Caller-ID display does not prove beyond the shadow of a doubt that the call originated from the displayed number.

How to deal with an offensive call

o Use the new call trace mechanism to create a record suitable for evidence in court. You can also get the teleco's nuisance bureau and appropriate law enforcement authorities to investigate for you by following up on the call you traced with those authorities. Use the Automatic Call Rejection service to make sure you do not receive any further calls from that number.

7 Selective Call Rejection (SCR) Price.

The monthly charge for selective call rejection proposed in the tariff is $4.00 for residential home and $4.50 for businesses.

SCR is a significant solitude enhancing feature, and should be provided it at a rate that will encourage its widespread use. But to be a viable product its price must be lower than the cost of using Caller-ID plus call-rejecting CPE which provides superior functionality.

The problems with the SCR service involve the absurdly small number of calling numbers that can be rejected, and the fact that anonymous calls cannot be rejected. Using CNID plus CPE will not suffer these drawbacks.

One significant advantage of Selective Call Rejection over Caller-ID plus CPE is that it can be used to reject repeated calls from a specific blocked number even when the user does not know the blocked number. This is the principle reason the SCR service is worth saving from the disuse it would suffer if priced too high.

Customers will have an additional tool to protect the peace and quiet of their homes if this feature is provided at a reasonable cost.


On the Balancing Act

As in previous US West documents, the statement is made that a balance must be achieved between a callers anonymity and a callee's solitude. This disheartening conclusion is reached by ignoring most of the things that happen in a typical telephone interaction in the CNID environment.

o The whole point of CNID is to allow the caller and callee to more efficiently exchange roles and share information about each other with others. An analysis that pits the "caller" against the "callee" hides the interesting part of the interaction which only begins when they are allowed to switch roles.

o The CNID service by itself does not provide any significant solitude. Telephone solitude can be obtained by using tools like Selective Call Acceptance, Selective Call Rejection, Anonymous Call Rejection, and best of all, a closely held unlisted number. Caller ID gives you some control on who you choose to speak with, but doesn't reduce the number of people who can disturb the household. A gate-keeper who keeps the riffraff at bay with little supervision provides solitude. CNID is equivalent to a hazy peep-hole. You can sometimes see who's ringing, but they can just keep on ringing.

o The needs and legal rights for solitude that residential customers have is greater than that which businesses have.

The future solitude of a caller depends upon their ability to make calls anonymously. Solitude requires anonymity. We can have both or neither, and by attempting to balance the two we will wind up with neither.

On Software Changes

As software engineers, we have broad experience with user interface changes in complex systems. We find US West's cost estimates for their software changes incomprehensibly high. If SS7 switch software is really so complex as to make simple fixes so expensive, routine bug maintenance and enhancements will cost many times these estimates. Consequently, if US West's estimates for minor modifications are accurate, CPSR shudders to contemplate the costs USW will ultimately attempt to recover as other trivial problems with SS7 technology arise that need attention.

With no specific motivation it might take years to get a minor switch software change from Bellcore and the switch vendors. But they, like other unregulated competitive for-profit companies, can be pressured by holding up a large sale until they provide the right technical solution. It may turn out that when the profitability of the deal is threatened, the switch vendors will find more efficient ways to make the needed changes. If Oregon doesn't hold up or threaten CNID revenue, it really could be years before we get safe and convenient service.

Certificate of Service.

These comments are being mailed or faxed to the parties of UM 365 and UT 115 as listed on the August 18th UM 365 service list from the Oregon PUC plus the one later addition.

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Created before October 2004

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