Abstract:
An apparatus ( 100 ) for interfacing a telephone ( 12 ) with a telecommunications network ( 24 ). The telephone provides and accepts digital signals ( 118 ) and the telecommunications network provides and accepts analog signals ( 124 ). The digital signals include digital control content ( 120 ) and digital voice content ( 122 ), and the analog signals include analog control content ( 126 ) and analog voice content ( 128 ). A control circuit ( 142 ), a first port ( 106   b ), and a second port ( 110   b ) are provided. The first port communicates the digital signals to and from the control circuit. The second port communicates the analog signals to and from the control circuit. The control circuit converts the digital control content to the analog control content, and vice versa. The control circuit also converts the digital voice content to the analog voice content, and vice versa.

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates generally to telephonic communications, and more particularly to terminal interface circuitry. 
     2. Background Art 
     On Sep. 8, 2011 and into the morning of September 9, an electric power failure affected the lives of approximately five million people across southwestern Arizona, San Diego and adjacent areas in California, and northwestern Mexico. The cities of San Diego and Tijuana bore the brunt of this disaster, which started slightly before 4 p.m. PDT and the beginning of a Thursday evening commuter rush hour. 
     In San Diego, Calif. 13 police stations were left without power but were able to continue operating and taking 911 calls by using generators. In southern Orange County, Calif., the sheriffs department dispatched deputies to busy intersections because traffic lights were out. Essentially all of the traffic lights in Tijuana, Mexico were also out. As evening progressed street lights in San Diego and Tijuana stayed dark and gas stations were unable to pump gas. In Tijuana, power was cut to hospitals and government offices. In the affected areas of Arizona and California, hospitals operating their own power sources generally faired well, even with having to handle increased patient loads due to auto accidents and heat related medical emergencies (temperatures were un seasonal, with highs in much of the affected area ranging from 100° F. to 118° F.). 
     Of particular relevance here, as MSNBC euphemistically reported, “mobile phone networks were spotty.” In the days following September 8 th  users of Professor Piggington&#39;s Econo-Almanac blog reported their own observations:
         TMobile voice and data worked in most [but not all] areas.   I use TMobile and it barely worked. I would be able to dial out and then it would quit.   Cell coverage (Verizon) was less than wonderful in the late afternoon. I assume because everyone was calling everyone else to say they were stuck in traffic . . . . Cell coverage was fine in the evening.   ATT worked on our i-Pad, but very slow. Went down a couple of times, then worked again.   AT&amp;T service on unlocked non-smart phone worked until about 5:45 p.m. yesterday, then displayed “No Network Coverage” until this morning.       

     One blog commenter, signing as “CE,” summed up this event as a learning experience (misspelling in the original):
         So there are a couple of things that are good to know.   One.   Land Line systems have their own power supply. The system is on a large battery bank and the generators are required, by FCC mandate, to have several days worth of fuel to support.   Two.   Most cell sites, now, have six hours of battery back up but sometime this won&#39;t go six hours due to extremely large loads at the cell.   Three.   Here is the stupid part. Some cell sites have fiber to them instead of T1s. While the FCC mandated that the cell sites has 6 hours of battery back up the fiber converter that translate DS0s only has two hours. So the site could keep going except its backhaul has dropped off. Mean while . . . Like I said earlier cell sites that are connected via T1s should remain up for the duration of the cell sites batteries.   Four.   VOIP systems will fail because you do not have a local power supply. IDCs will have power, the same way that local land line switches do, and the connection is still there but the local receiver (modem) will not have power . . . .       

     The above event was not unique, even in North America. For example, in 2008 a blackout in southern Florida affected 4.5 million customers for hours. The biggest blackout in the U.S. occurred on Aug. 14, 2003, disrupting power in eight U.S. states and Ontario, Canada. Over 55 million people were affected, with service in major cities, such as New York and Toronto, not fully restored for two days. 
     One thing that has changed since 2003 and even 2008, however, is the increasing usage of mobile telephones and the degree of reliance that out society places on these. The 2003, 2008, and 2011 events serve to illustrate that we have an existing and growing problem in our telecommunications infrastructure. 
     [In the following, reference numbers are used to denote generic or collective elements, and reference numbers with letter suffixes are used to denote specific elements or types of elements. For example, telephones  12 , generic, versus a POTS telephone  12   a  and cell phones  12   d , specific.] 
       FIGS. 1   a - b  (background art and prior art, respectively) depict a very basic telecommunications network  10 , wherein  FIG. 1   a  is a block diagram showing network elements and  FIG. 1   b  is a stylized depiction of these network elements in use. The telecommunications network  10  here comprises two telephones  12   a - b  connected by a communications channel  14 . 
       FIG. 2  (background art) depicts a slightly more sophisticated but still rather basic telecommunications networks  10 . Here two telephones  12   a - b  are connected to respective subscriber sub-channels  16   a - b , that in turn connect to respective aggregation nodes  18   a - b , which are connected by an inter-provider sub-channel  20 . 
     Many labels in telecommunications have become obsolete. For example, subscriber sub-channels  16  have often been termed “local loops,” “landlines,” and the “last mile,” due to the historic use of analog signals in copper wire pairs in pole supported cables connected to necessarily nearby aggregation nodes  18 . Today these labels are too limiting (e.g., for cellular telephone service). Similarly, aggregation nodes  18  have often been termed “central offices” or “switches,” due to the historic use of switches located at telephone service provider offices. Today these labels are also too limiting (e.g., field-located digital loop carrier (DLC) units and serving area interfaces (SAI)). Also similarly, inter-provider sub-channels  20  have often been termed “trunk lines,” due to the historic use of multi-conductor cables or lines. Today that label as well is too limiting (e.g., satellite links). In general, the use of historic but obsolete labels is avoided herein. 
     In telecommunications today, hundreds of millions of telephones  12  and their respective subscriber sub-channels  16  are serviced by hundreds of thousands of aggregation nodes  18 , that in turn are connectable with tens of thousands of inter-provider sub-channels  20 . At the end of 2009 there were nearly 6 billion mobile and fixed-line subscribers worldwide, comprising 1.26 billion fixed-line subscribers and 4.6 billion mobile subscribers. (John, Richard R., Network Nation: Inventing American Telecommunications, Harvard University Press, 2010). 
       FIG. 3  (background art) depicts three representative communications examples in a modern telecommunications network  10 . In the first example, telephones  12   a - b  are connectable via a first communications channel  14   a . For the sake of this discussion let us say that we have a real estate broker in a small office in rural North America who is calling her home a few blocks away, to leave a message for her children. 
     The telephones  12   a - b  here are respectively connected via subscriber sub-channels  16   a - b  to a single aggregation node  18   a . The office telephone  12  here is a plain old telephone service (POTS) type device (POTS telephone  12   a ), and it is especially notable here for two reasons. First, subscriber-side POTS telephones  12   a  are provider-side powered (e.g., from the aggregation node  18   a  here). Second, signals between a POTS telephone  12   a  and an aggregation node  18   a  are analog. 
     In contrast, home telephone  12  here is a common cordless telephone  12   b  having a base station portion and a hand set portion intercommunicate using radio frequency signals. The base station portion is powered from a small plug-in transformer, that in turn is powered with building mains power from a wall outlet. The hand set portion is portable and is powered from an internal battery, which is recharged when the hand set portion is placed in the base station portion. The radio frequency signals used may be analog or digital. Nonetheless, it is analog signals that are used between the cordless telephone  12   b  and at least part of the way to the aggregation node  18   a.    
     [Telephone service via coaxial and fiber optic cables are special cases where analog-digital conversion is made, usually where the service enters the premises, and the signals onward to the aggregation node are digital. Service such as this is increasingly common where households have combined cable TV, Internet, and telephone combination service. However, such telephone service is not particularly germane here.] 
     Continuing, the subscriber sub-channels  16   a - b  here are both traditional copper wire pairs connected to the local aggregation node  18   a.    
     In the second example in  FIG. 3 , telephones  12   a ,  12   c  are connected via a second communications channel  14   b . Continuing with our hypothetical real estate broker, let us now say that she calls the hotel room of clients who are vacationing in Europe, to inform them that an offer they made on a property has been accepted. Proceeding from left to right, the office POTS telephone  12   a  connects via the subscriber sub-channel  16   a  to the local aggregation node  18   a ; the aggregation node  18   a  connects via inter-provider sub-channel  20   a  to the aggregation node  18   b ; the aggregation node  18   b  connects via inter-provider sub-channel  20   b  to the aggregation node  18   c ; the aggregation node  18   c  connects via inter-provider sub-channel  20   c  to the aggregation node  18   d ; the aggregation node  18   d  connects via inter-provider sub-channel  20   d  to the aggregation node  18   e ; and the aggregation node  18   e  connects via subscriber sub-channel  16   c  to the hotel room telephone  12  here, which is a Voice over Internet Protocol device (VoIP telephone  12   c ). 
     The POTS telephone  12   a , subscriber sub-channel  16   a , and aggregation node  18   a  have already been discussed, and the elements between aggregation node  18   a  and aggregation node  18   e  are not particularly germane here. The VoIP telephone  12   c  here is notable for two reasons. First, VoIP telephones  12   c  are subscriber-side powered, usually from a local interface device like a router that receives building power. Second, signals between VoIP telephones  12   c  and aggregation nodes  18   e  are entirely digital. 
     In the third example in  FIG. 3 , telephones  12   c ,  12   d  are connected via a third communications channel  14   c . Continuing now with our hypothetical European vacationers, let us say that the husband receives the real estate agent&#39;s call but that his wife is away from the hotel shopping. He therefore uses the hotel room&#39;s VoIP telephone  12   c  to call her cell phone  12   d  to inform her of the offer acceptance. The VoIP telephone  12   c  accordingly connects via the subscriber sub-channel  16   c  to the local aggregation node  18   e ; the aggregation node  18   e  connects via inter-provider sub-channel  20   e  to aggregation node  18   f ; and the aggregation node  18   f  connects via subscriber sub-channel  16   d  to the cell phone  12   d.    
     The VoIP telephone  12   c , subscriber sub-channel  16   c , and aggregation node  18   e  have already been discussed, and the inter-provider sub-channel  20   e  here is also not particularly germane. The cell phone  12   d  here is battery powered, with the battery being rechargeable via a universal serial bus (USB) port in the cell phone  12   d . Intercommunication here over the subscriber sub-channel  16   d  is via radio waves. 
       FIG. 4  (background art) is a simplified version of  FIG. 3 , with some pertinent information added and some minor changes made to facilitate discussion. For present purposes, everything between the aggregation nodes  18  here is presented as generic inter-provider sub-channels  20  connecting with a central cloud  24 .  FIG. 4  depicts the cellular aspects of the telecommunications network  10  slightly different than in  FIG. 3 . Here everybody has a cell phone  12   d  and there are ubiquitous sets of cellular aggregation nodes  18   f . Also, for completeness and later discussion a generic power source  26  is depicted. 
       FIG. 4  serves now to discuss some generalizations about the history of telephony. Today we have, plain old telephone service (POTS), public switched telephone network (PSTN) service, and cellular service all coexisting and in wide use. The POTS telephone  12   a , the cordless telephone  12   b , and the subscriber sub-channels  16   a - b  here employ what is widely termed “POTS technology.” The VoIP telephone  12   c , the subscriber sub-channel  16   c , and the aggregation node  18   e  employ digital Internet Protocol (IP) technology. The cell phones  12   d , the subscriber sub-channel  16   d , and the aggregation nodes  18   f  employ radio based digital “cellular technology.” Additionally, the aggregation nodes  18   b - f , the inter-provider sub-channels  20 , and the cloud  24  employ digital “PSTN technology” or Internet Protocol (IP) technology, with the aggregation nodes  18  typically interfacing between respective technologies as needed. 
     Generalizing, POTS technology is analog and PSTN technology is digital. Starting in the early 1960&#39;s, analog POTS in the telecommunications network  10  started to be converted over to digital PSTN, and digital IP and cellular technologies subsequently followed. The process of analog to digital equipment conversion is near complete, except for some telephones  12  and subscriber sub-channels  16 . In the interest of backwards compatibility, many local aggregation points  18  still can handle analog POTS communications. 
     POTS and PSTN services were historically subject to different political considerations than the newer cellular and VoIP services. POTS grew during the early years of the cold war, PSTN grew during the later years of the cold war, and cellular and VoIP have grown in the post cold war era. 
     POTS and PSTN were viewed as critical national infrastructure. Few today remember when POTS was the only service available. In contrast, many today appreciate that the Internet was developed adjacent with and melded with PSTN. The widely accepted notion that the Internet was designed to survive a nuclear attack serves to emphasize just how robust most POTS and PSTN services were and continue to be designed. Also, POTS and PSTN largely necessitated monopolies for their efficient operation, and governments therefore dictated many aspects of design and strongly regulated the major market participants. 
     In contrast, cellular and VoIP technologies have grown largely as parallel options to POTS and PSTN in most places, and these technologies do not necessitate monopolies. Governments have therefore not generally had the justification or motivation to dictate design or regulate market participants. 
     Turning now particularly to cellular technology, the overwhelming considerations for it have been lowest pricing and newest features. Today cell phones  12   d  are often given away to subscribers in exchange for 1-2 year service contracts and the life cycle of a cell phone, from design through to obsolescence, can be as little as two years. 
     Over the shorter history of cellular service, some aspects of cell phones  12   d  have and continue to become standardized. For example, the rightmost cell phone  12   d  in  FIG. 3  was described above as being a “smart phone,” with a USB port that doubles as a power connection port. This power arrangement has become largely standard for all new cell phones  12   d  today. Similarly, many new cell phones  12   d  use hardware (e.g., digital signal processors) and software (e.g., the Android™ operating system) that permit very flexible yet powerful software applications. For instance, a Motorola Droid™ device inherently has radio frequency coverage for cellular bands, Wi-Fi, and Bluetooth™, but can be programmed to handle essentially any protocol that uses the same or close radio frequencies. Moreover, while cellular telephone programming historically has required considerable specialized talent and entailed substantial learning of the target device, the emerging use of standard operating systems (e.g., Google&#39;s Android™ OS) increasingly permits those with barely any programming talent to create their own software applications in a few hours. 
     The overwhelming consideration for VoIP service has been very low cost of operation. Aside from an initial equipment investment, VoIP is almost free and its cost is not tied to the amount of usage. Today VoIP telephones  12   c  are increasingly common in business environments, because most business have Internet connectivity and are motivated to minimize operating costs. Nonetheless, some recently variations of VoIP have become popular with travelers and in home environments. Probably the two most well known of these are Skype™ and MagicJack™. 
     Skype™ is a software application that allows users to make voice and video calls and chat over the Internet. Calls to other users within the service are free, while calls to traditional POTS/PSTN telephones and cell phones can be made for a fee. Many subscribers are business travelers who use laptop or tablet computers to make economical long distance calls. If a computer or computerized device has a microphone and a speaker it can likely be used. Alternately, handsets or head sets that plug into a USB port of a computer or computerized device can be bought for use with the service. 
     MagicJack is a device that plugs into a USB port on a user&#39;s computer and that has a standard RJ-11 phone jack into which any standard POTS/PSTN telephone can be plugged. The User&#39;s computer must have Internet access, but then is able to make calls to almost any phone in the U.S. and Canada. 
     Changing tact now, let us consider how the telecommunications network  10  in  FIG. 4  can fail. Failures can generally be classified as equipment breakdown, equipment overload, and underlying infrastructure failure. 
     Equipment breakdown is straightforward. One can minimize this by building more robust equipment or one can mitigate this by providing redundancy. In the case of the cloud  24 , both approaches are widely employed. The cloud  24  can be spoken of as being a part of, as itself being, or as including the Internet, and it can be recalled here that the Internet was purportedly designed to withstand nuclear attack. 
     In contrast, telephones  12  vary considerably in their resistance to breakdown. Some are wonders of robustness, whereas others breakdown easily. Many older style POTS telephones  12   a  are very robust, largely due to their original design having occurred when redundancy was rare and expensive (e.g., a telephone was a substantial investment, often leased from the TelCo on a monthly basis), and one telephone per home was felt sufficient. Business telephones  12  (e.g., VoIP telephone  12   c ) are typically next in robustness, largely due to businesses being willing and able to pay for increased reliability, and seeking to reduce operating costs. Modern household telephones  12  (e.g., cordless telephone  12   b ) are usually another matter. These are widely regarded as a cheap commodity and they are typically replaced every 2-3 years, if for no other reason than that consumers want newer features. Portable telephones  12  (e.g., cell phones  12   d ) are generally the most subject to breakdown. This is due partly to their inherently being subject to a higher level of abuse. Regarded also as a cheap commodity, these are also usually expected to only last 1-2 years, until a replacement is obtained with a new service agreement or until a superseding model with newer features becomes available. In passing here, it should also be noted that cordless telephones  12   b  and cell phones  12   d  have batteries that can completely discharge (effectively resulting in a temporary breakdown) or that can literally breakdown. As  FIG. 4  indirectly implies, we now have a considerable amount of redundancy in telephones  12  today, particularly due to cell phones  12   d  becoming essentially ubiquitous in modern society. 
     Subscriber sub-channels  16  also vary considerably in their resistance to breakdown. Suffice it to say that what can reasonably be done to make these more robust usually is done. As for redundancy, subscribers can pay for multiple lines, but adjacent subscriber sub-channels  16  tend to fail together (e.g., by a cable being cut). 
     The resistance to breakdown of local aggregation nodes  18  (e.g., aggregation nodes  18   a ,  18   e ,  18   f ) also varies. A lot of the “survive nuclear attack” design is still found in almost all non-cellular type aggregation nodes  18 , and even smaller, local instances are usually robustly built with considerable internal redundancy. In the United States and many other countries, non-cellular aggregation nodes  18  are usually battery powered, with charging systems that have at least one back-up power source. Back-up generators and fuel supplies that will last at least for hours are mandated by government regulations. 
     Aggregation nodes  18  for cellular service are often markedly different. In a cellular scheme each local node is often part of an overlapping grid. If one breaks down, others may be able to seamlessly cover. Additionally, lulled into a sense of security because POTS and PSTN widely exist, consumer concern and government involvement is often considerably less here. Notably, where there are government regulations requiring back-up generators, the requirements for fuel supplies are lower than such for non-cellular aggregation nodes  18 . 
     Continuing with how the telecommunications network  10  in  FIG. 4  can fail, equipment overload is a rapidly growing but underappreciated possibility. POTS and PSTN services generally have much higher resistances to overload than cellular services. The history of POTS and PSTN as critical communications infrastructure, and close government design and regulatory involvement, have resulted in these having high capacity to subscriber ratios. For instance, if there is a natural or man-made disaster and 10% of POTS or PSTN subscribers concurrently attempt to make calls, most if not all will get a dial tone, be able to enter a telephone number, and be able to call across the street or around the world. In contrast, if there is a similar disaster and 10% of cellular subscribers concurrently attempt to make calls, the cellular services will likely overload or outright crash. 
     Continuing further with how the telecommunications network  10  in  FIG. 4  can fail, we come to underlying infrastructure failure. In general, this means power failure. 
     The older style POTS telephone  12   a  fairs best here. It is line powered, meaning that it receives all necessary power for operation from its local aggregation node  18 , via copper wires in the subscriber sub-channel  16 . The cell phone  12   d  also tends to fair well when the electric power goes off. It is, however, subject eventually to battery depletion, say from repeated unsuccessful attempts to get through on an overloaded cellular service. 
     The cordless telephone  12   b  and the VoIP telephone  12   c  do not fair at all here, at least not without a backup power source (which is uncommon and in some cases simply will not help anyway). Recall that cordless telephones  12   b  and the VoIP telephones  12   c  employ local power sources, such as standard wall power outlets. 
     Accordingly, in view of our increasing reliance on easily disrupted power sources for localized telephone communications, what is needed is a mechanism to decrease such reliance. In particular, in view of the advantageous power-related features of analog POTS and PSTN technologies and the disadvantageous fact that consumer&#39;s digital telephonic-capable devices today cannot utilize such power-related features, such a mechanism should permit consumer&#39;s digital telephone devices to interface with provider&#39;s analog telephone services. 
     BRIEF SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide an interface between digital signals at a telephone and analog signals at a telecommunications network. 
     Briefly, one preferred embodiment of the present invention is an apparatus for interfacing a telephone with a telecommunications network. The telephone provides and accepts digital signals and the telecommunications network provides and accepts analog signals. The digital signals include both control and voice content, and the analog signals similarly include both control and voice content. A control circuit, first portal, and second portal are provided. The first portal communicates the digital signals to and from the control circuit and the second portal communicates the analog signals to and from the control circuit. The control circuit converts the digital contents into analog contents, and vice versa. 
     These and other objects and advantages of the present invention will become clear to those skilled in the art in view of the description of the best presently known mode of carrying out the invention and the industrial applicability of the preferred embodiment as described herein and as illustrated in the figures of the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
       The purposes and advantages of the present invention will be apparent from the following detailed description in conjunction with the appended figures and tables of drawings in which: 
         FIGS. 1   a - b  (background art and prior art, respectively) depict a very basic telecommunications network, wherein  FIG. 1   a  is a block diagram showing network elements and  FIG. 1   b  is a stylized depiction of these network elements in use. 
         FIG. 2  (background art) depicts a slightly more sophisticated but still rather basic telecommunications networks. 
         FIG. 3  (background art) depicts three representative communications examples in a modern telecommunications network. 
         FIG. 4  (background art) is a simplified version of  FIG. 3 , with some pertinent information added and some minor changes made to facilitate discussion. 
         FIG. 5  is a schematic block diagram that shows an overview of an example telephone interface and an environment in which it may be used. 
         FIG. 6  is a schematic block diagram showing major features as well as some optional features of a telephone that is suitable for use with the telephone interface. 
         FIGS. 7   a - b  are schematic block diagrams showing major features as well as some optional features of the telephone interface ( FIGS. 7   a - b  are the same except for the formats of labeling). 
         FIG. 8  is a flow chart of an interface process that the inventive telephone interface may employ. 
         FIGS. 9   a - b  show tables, wherein  FIG. 9   a  includes TBL. 1 and  FIG. 9   b  includes TBL. 2, and wherein TBLS. 1-2 show the dual-tone frequencies conventionally used in North American telephony to represent telephone numbers and various other standardized signals. 
       In the various figures of the drawings, like references are used to denote like or similar elements or steps. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A preferred embodiment of the present invention is a Telephone Interface. As illustrated in the various drawings herein, and particularly in the views of  FIGS. 5 and 7   a - b , embodiments of the invention are depicted by the general reference character  100 . 
     Briefly and somewhat generalizing, it has been the present inventor&#39;s observation that we today have many excellent analog and digital telephone technologies; and that we have mechanisms to interface subscriber-side analog telephone technology with service provider-side digital telephone technology; but that we do not have a mechanism to interface subscriber-side digital telephone technology with service provider-side analog telephone technology. As just one example, one cannot plug their cell phone into a standard RJ11 telephone wall jack to make a call. As the above discussed examples have implied, however, there are situations, such as human and natural disasters, where it is desirable to be able to employ the more robust and reliable features of POTS and PSTN. 
       FIG. 5  is a schematic block diagram that shows an overview of an example telephone interface  100  and an environment  102  in which it may be used. Largely conventional elements here are the telephone  12  and the cloud  24 , both of which are what the telephone interface  100  interfaces between. Some important features of the telephone  12  here are that it has an added programmed application  104 , and a first subscriber-side port  106   a  that connects via a subscriber-side channel  108  to a second subscriber-side port  106   b  in the telephone interface  100 . The cloud  24  here is essentially the same as that discussed in the background section, except that the cloud  24  here is extended to a first provider-side port  110   a  that connects via a provider-side channel  112  to a second provider-side port  110   b  in the telephone interface  100 . 
     Digressing briefly, TBLS. 1-2 show the dual-tone frequencies conventionally used in North American telephony to represent telephone numbers and various other standardized signals. This scheme is frequently referred to as dual-tone multi-frequency (DTMF). Older single-tone schemes are still used in some locations, and there is considerable regional variation in the specific tones, cadences, voltages, and currents used. 
     Continuing with  FIG. 5 , the environment  102  here has a digital sector  114  and an analog sector  116 , as shown. In the figures the various signals and their contents are stylistically depicted with references to facilitate discussion. 
     The digital sector  114  includes the first subscriber-side port  106   a , the subscriber-side channel  108 , and the second subscriber-side port  106   b  all via which digital signals  118  are inter communicated between the telephone  12  and the telephone interface  100 . The digital signals  118  are characterized by containing digital control content  120  and digital voice content  122 . Some typical examples of the digital control content  120  are digital codes representing the contents of TBLS. 1-2. The digital voice content  122  is as implied, that is, digitized speech. The specific nature of the digital signals  118  is set by whatever protocol is used across the digital sector  114  by both the telephone  12  and the telephone interface  100 , e.g., USB, Bluetooth, WiFi, ZigBee, etc. 
     The analog sector  116  includes the first provider-side port  110   a , the provider-side channel  112 , and the second provider-side port  110   b  all via which analog signals  124  are inter communicated between the telephone  12  and the telephone interface  100 . Some typical examples of the analog control content  126  are the analog tonal signals represented in TBLS. 1-2. The analog voice content  128  is also as implied, that is, analog speech. The specific nature of the analog signals  124  is set by whatever protocol is used across the analog sector  116  by both the cloud  24  and the telephone interface  100 . 
       FIG. 6  is a schematic block diagram showing major features as well as some optional features of a telephone  12  that is suitable for use with the telephone interface  100 . In addition to the already noted programmed application  104  and the subscriber-side port  106   a , the telephone  12  has a sound input transducer  130 , e.g., a microphone, and a sound output transducer  132 , e.g., a speaker. Optionally, the telephone  12  may have a user input transducer  134 , e.g., a keypad or touch screen. It is anticipated that most telephones  12  used with the telephone interface  100  will have this option, but it should be noted that it is not necessary. 
     Also optionally, the telephone  12  may have a power source  136  and a memory  138 . For instance, if the telephone  12  is a cell phone  12   d  its battery will be the power source  136 . Similarly, if the telephone  12  is a smart type of cell phone  12   d , for example, it typically will have a memory  138 , say, to hold user entered data such as telephone numbers, e-mail addresses, etc. 
     Continuing with  FIG. 6 , the telephone  12  has a controller  140  that is suitable to execute the programmed application  104  and to operate all of the other features that are present. 
     A telephone  12  for use with the telephone interface  100  typically will be distinguished from telephones in general by not having the capability for direct connection to a POTS or PSTN type service. For instance, the telephone  12  used here can particularly be a cell phone  12   d . Alternately, the telephone  12  may be a member of a larger set of devices that are not usually regarded as telephones. For example, some computerized tablets, laptop computers, and personal computers are suitable for use as the telephone  12 . 
       FIGS. 7   a - b  are schematic block diagrams showing major features as well as some optional features of the telephone interface  100  ( FIGS. 7   a - b  are the same except for the formats of labeling). In addition to the already noted subscriber-side port  106   b  and the provider-side port  110   b , the telephone interface  100  has control circuitry  142 . Optionally, the telephone interface  100  may have subscriber-side conversion circuitry  144 , provider-side conversion circuitry  146 , a power source  148 , a user control  150 , and a memory  152 . If the memory  152  is present, it then may be a static type of memory that stores one or more optional interface applications  154 . 
     As implied above, the only strictly necessary features of the telephone interface  100  are the subscriber-side port  106   b , the control circuitry  142 , and the provider-side port  110   b  (and some manner of housing these). When connected to the telephone  12 , the subscriber-side port  106   b  may be able to receive sufficient power to partially or fully operate the control circuitry  142 . Alternately or additionally, when connected to the cloud  24 , the provider-side port  110   b  may be able to receive sufficient power to partially or fully operate the control circuitry  142 . Granted, such parasitically powered embodiments of the telephone interface  100  will impose requirements on the control circuitry  142  that may be difficult or impractical to overcome (e.g., higher cost, susceptibility to EMI, etc.), but even such minimalist embodiments are within the spirit of the present invention. 
     It is anticipated that many embodiments of the telephone interface  100  will have the subscriber-side conversion circuitry  144  and also the provider-side conversion circuitry  146 , because many current candidates for the control circuitry  142  will not directly work with the signal levels from the subscriber-side port  106   b  and the provider-side port  110   b  (i.e., have matching voltage and current levels). For example, if the subscriber-side port  106   b  is a USB type port, 5 volt signal levels must be handled. If the provider-side port  126   a  is a typical U.S. standard POTS/PSTN type port, signal levels approaching 100 volts must be handled. In contrast, many microcontrollers today that are desirable for use in the control circuitry  142  operate at 1.8 or 3.3 volt levels. 
     Different approaches to constructing the subscriber-side conversion circuitry  144  and the provider-side conversion circuitry  146  are possible. Discrete components can be used, but it is anticipated that the more typical case will be to use already widely available integrated circuits and modules (e.g., from vendors such as Maxim Integrated Products, Texas Instruments, Panasonic, etc.). Many components suitable for interfacing USB, Bluetooth, ZigBee, etc. protocols to microprocessors are available, and thus are candidates for use in the subscriber-side conversion circuitry  144 . Similarly, many components suitable for interfacing modern electronic devices to POTS/PSTN are also available and are candidates for use in the provider-side conversion circuitry  146 . 
     [The inventor is presently working with a technician designing an embodiment using a Texas Instruments MSP430™ series micro processor. These processors have many desirable features, including a well developed knowledge base that includes telecommunications applications, as well as a relatively straightforward design path to more powerful devices if necessary. Many variations within the MSP430 series are available, including different clock speeds, memory types and capacities, power requirements, and analog to digital (ADC) and digital to analog (DAC) options. These processors also interface well with other useful modules and discreet-component circuits. For instance, Texas Instruments&#39; TUSB3410 integrated circuit is widely used to provide USB communications with MSP430 processors, and Roving Networks&#39; RN-42 and RN-171 modules can similarly provide Bluetooth and WiFi. When these devices are used, the need for subscriber-side conversion circuitry  144  is essentially eliminated. For provider-side conversion circuitry  146  (and considerably more, if desired) a device like Atmel&#39;s U4091 Programmable Telephone Audio Processor can be used, although the capabilities of this device will be grossly underutilized in most currently envisioned embodiments of the telephone interface  100 .] 
     Continuing, many candidates for the power source  148  also already exist. Obviously, a traditional battery is one such candidate. But use of such an easily exhausted power source  148  may be non-optimal in some embodiments of the telephone interface  100 . Other candidates are harvesting power from light, e.g., with a solar cell; harvesting power from a heat source, e.g., with a bi-metallic junction; harvesting power from human movement, e.g., with a micro-generator or piezoelectric element; or generating power from a one-time chemical reaction (distinguishable from traditional batteries that discharge even when not in use). 
     The user control  150  is straightforward and many suitable candidates for it also already exist, such as buttons and even speech control. This feature is one that the inventor feels is unlikely to appear in many embodiments of the telephone interface  100 . First, a user control  150  would be redundant with most candidates for the telephone  12 . Most suitable telephones  12  will already have user controls, some quite sophisticated, and those controls can be used to configure and control the telephone interface  100 , via the subscriber-side ports  106  and the subscriber-side channel  108 . Secondly, a user control  150  would require making the telephone interface  100  physically larger and less robust than may be desired. And third, the telephone interface  100  can be designed so that user control is simply not required. 
     In contrast, the memory  152  is a feature that the inventor feels is likely to be provided in many embodiments of the telephone interface  100 . The memory  152  in combination with the control circuitry  142  permit many optional features to be “programmed into” the telephone interface  100 . Some particularly powerful examples are the interface applications  154 . 
     Briefly, since usage is discussed in detail presently, the inventor anticipates that the telephone interface  100  will particularly be used in emergency situations. In an emergency, there are usually two key issues: what number is one going to call and how is that going to be done (e.g., standard, pre-paid, collect, enter-code-to-continue, etc.). An interface application  154  can handle both of these issues, by calling a pre-stored telephone number (and extension if appropriate) and by providing any codes, selecting appropriate options, etc. to complete a connection. 
     Embodiments of the telephone interface  100  with a single interface application  154  can operate entirely automatically, being manufactured or field programmed with the interface application  154  containing all necessary call information. That information can be a single number and how it is used, or it can be multiple detail sets, say, to be tried sequentially until a call is completed; or to be called depending on the time (e.g., day, night, holiday); on the user&#39;s present geographic location (e.g., based on the programmed application  104  in a location detecting smart cell phone  12   d  having indicated whether the user is in California or Oregon); or based on the local protocol used by the cloud  24  (e.g., automatically changing signal levels, frequencies, and conventions based on whether the telephone interface  100  is in North America or Europe); etc. Clearly, even a single interface application  154  can make the telephone interface  100  a very sophisticated tool. 
     Alternately, with even a minimal user control  150  or under control remotely from the telephone  12 , a single interface application  154  can be turned off or multiple interface applications  154  can be selected from. 
       FIG. 8  is a flow chart of an interface process  200  that the telephone interface  100  may employ. In a step  202  the interface process  200  starts. At this point a user has the telephone  12  and the telephone interface  100 . 
     In a step  204  the telephone  12  is initialized and in a step  206  the telephone interface  100  is initialized. The order of step  204  and step  206  may vary or overlap. 
     To initialize the telephone  12 , it is powered on and brought to the state that it has its standard functionality. That is, to the state at which it could be used to make a conventional telephone call or execute a conventional software application. Note if the telephone  12  is in a sleep state, activity at its subscriber-side port  106   a  may be one option to wake and trigger initialization. For instance, if the telephone  12  is a smart cell phone, connection of a cable at its USB port may trigger step  204 . 
     To initialize the telephone interface  100 , it is powered on and brought to the state it can communicate with the telephone  12  and the cloud  24 . In general, since the control circuitry  142  presumably will require at least some power to operate, the presence of power to the control circuitry  142  can trigger initialization. If the power source  148  is non deplete-able (e.g., a solar cell rather than a battery) the telephone interface  100  can exist in essentially a permanently initialized state. Alternately, the control circuitry  142  may have a very low power draw sleep mode where it monitors for and awakes upon any activity at any of the subscriber-side port  106   b , the provider-side port  110   b , or the user control  150 . Still alternately, the user control  150  can be used to turn on the telephone interface  100 , upon which initialization automatically then occurs. 
     One sophisticated option here is to have the telephone  12  and the telephone interface  100  communicate to automatically start or wake the programmed application  104  in the telephone  12 . For example, in essentially conventional manner for USB equipped devices, the telephone  12  can detect that something has been attached to its USB port (i.e., subscriber-side port  106   a ), query what that is and the telephone interface  100  can reply accordingly, and the telephone  12  then can have wake of start the programmed application  104 . 
     In a step  208  the telephone  12  initiates a call. If the programmed application  104  is not already running, it is executed. If the programmed application  104  has pre-set call details (telephone number to call and manner in which to place the call), those are communicated to the telephone interface  100 . Alternately, such call details can be default values in the programmed application  104  that the user of the telephone  12  can override with the user input transducer  134 . Still alternately, the user can enter the desired call details with the user input transducer  134 , or select from an existing database of call details in the telephone  12 . 
     Further here in step  208 , the programmed application  104  operates the telephone  12  such that voice communications signals travel via the channel comprising the subscriber-side port  106   a , rather than via the other channels that may be available to the telephone  12 . For instance, if the telephone  12  is a cell phone  12   d  that conventionally handles calls in radio channels and the subscriber-side port  106   a  is a USB port, the cell phone  12   d  will now use the subscriber-side port  106   a  for calls, much in the manner that an earphone-microphone headset can be connected to the USB port of a personal computer to carry audio signals. 
     In a step  210  the telephone interface  100  initiates the call. More specifically, it has received the call details from the telephone  12  or it already has those details hard-wired or in an interface application  154 . What is received from the telephone  12  triggers the use of the now present details. In passing, the telephone  12  can provide additional information to be used by an interface application  154  (e.g., location, time of day, etc.). The control circuitry  142  initiates connection with the cloud  24 . In passing here, this may entail sensing what protocols are used by the cloud  24  (e.g., voltage levels) or negotiating for common protocols (e.g., signal frequencies). Further here in step  210 , the telephone interface  100  provides the call details to the cloud  24 . 
     In a step  212  the cloud  24  connects the telephone interface  100 , and thus the telephone  12  to a telephone device of a remote party. This can be done in entirely conventional manner in the cloud  24 , since the telephone interface  100  handles all interfacing necessary for the cloud  24  to “see” it as just another PSTN device. If the call cannot be completed by the cloud  24 , in straightforward manner, conventional signals are communicated back to the telephone interface  100 , and thus to the telephone  12 . 
     In a step  214  the cloud  24 , the telephone interface  100 , and the telephone  12  (running the programmed application  104 ) process the body of the call. For instance, the remote party says “hello” and the user of the telephone  12  replies and a conversation ensues. 
     In a step  216  one party terminates the call, typically in entirely conventional manner by hanging up. If the remote party hangs up, the cloud  24  detects this and signals the telephone interface  100 . Conversely, if the user of the telephone  12  hangs up, the telephone interface  100  detects this and signals the cloud  24 . 
     In a step  218  the telephone interface  100  wraps up and in a step  220  the telephone  12  wraps up. The order of step  218  and step  220  may also vary or overlap. 
     Finally, in a step  222  the interface process  200  stops. 
     It is anticipated that the interface process  200  will be all that many embodiments of the telephone interface  100  are used for. But more sophisticated embodiments of the telephone interface  100  can handle more complex scenarios. For instance, appreciation of the call-placing interface process  200  in straightforward manner now suggests a call-receiving capability. 
     Let us say that a user of the telephone  12  is a paramedic who&#39;s skills are likely to be needed in a natural disaster, and let us say that the other party is a dispatcher in a regional disaster management center. At 5:05 pm on a Friday afternoon, in the middle of the commuter rush hours, an earthquake occurs on the New Madrid Fault located South of St. Louis, Mo. 
     Major utility company power goes off immediately, due to equipment failures as well as precautionary automatic shutdowns of power generation facilities. Note, this will particularly include the many nuclear power plants within a thousand mile radius of St. Louis. 
     Our hypothetical paramedic has had a day off and is visiting her parents in the northwestern suburb of Maryland Heights, which is some miles away from central St. Louis and the major hospitals where her services can best be used. After the earthquake, the mobile phone networks are more than just spotty, they are overwhelmed and have outright crashed. But our paramedic here has a cell phone  12   d  and a telephone interface  100 , and her parents have a typical cordless telephone  12   b . Of course, the cordless telephone  12   b  will not operate because, even though the handset batteries are fully charged, the base station is powered from a standard 120 VAC wall socket and that power is off. However, our paramedic simply connects her cell phone  12   d  to her telephone interface  100 , unplugs the telephone cable (part of the subscriber-side channel  16   b ) to her parent&#39;s cordless telephone  12   b , and then plugs it into her telephone interface  100 . POTS/PSTN are up. In fact, due to so many telephones now relying on mains power in some manner, POTS/PSTN are carrying only 10% of what would be a normal usage load. 
     Our paramedic forthwith calls the regional disaster management center and is connected to the dispatcher. She explains where she is at and notes that traffic, downed bridges, etc. are preventing her from being able to help, and she suggests that the dispatcher advise her of a location within walking distance where she can help or where a helicopter passing through the area might provide her with a ride to a major trauma center. And the dispatcher says “how can I get back to you on that?” 
     Simple. She provides her parents telephone number and hangs up. In due course her cell phone  12   d  goes into power saving sleep mode, a state in which it can wait for calls for days before it becomes necessary to recharge the battery (i.e., the power source  136 ). Waiting long here is not necessary, however, because in 15 minutes the dispatcher does call back, and the telephone interface  100  puts the call through to the paramedic&#39;s cell phone  12   d , and she is instructed to go to a grade school softball field four blocks away and expect transport in 20 minutes. 
     While various embodiments have been described above, it should be understood that they have been presented by way of example only, and that the breadth and scope of the invention should not be limited by any of the above described exemplary embodiments, but should instead be defined only in accordance with the following claims and their equivalents. 
     INDUSTRIAL APPLICABILITY 
     The present telephone interface  100  is well suited for application in modern telecommunications networks  10 . For example, as a separate device used with a cell phone  12   d  or other suitable telephone  12 , many new capacities are added. Another option here is to integrate the telephone interface  100  literally into suitable future telephones  12  or into facilities in existing or newly being constructed buildings (an example of the latter is discussed presently). 
     Without limitation, a suitable telephone  12  with the telephone interface  100  can permit communications where cellular service does not reach (e.g., remote rural areas); where cellular service is overloaded (e.g., as in the 2003, 2008, and 2011 infrastructure failure examples noted herein); where cellular service is not secure (e.g., subject to monitoring or to caller location determination); where cellular service is not permitted (e.g., around sensitive electronic systems in airplanes and hospitals); or where cellular service is outright blocked (e.g., jammed or disrupted by high sunspot activity). While telephones  12  with radio frequency based subscriber-side channels  108 , e.g., Bluetooth, WiFi, and ZigBee, may be subject to similar concerns, telephones  12  with other types of subscriber-side channels  108  can serve, e.g., USB. 
     Additionally, a suitable telephone  12  and the telephone interface  100  can permit communications when cellular service is fully available or its presence is simply not a consideration. For instance, an old cell phone  12   d  can be plugged into a POTS/PSTN RJ11 jack (via the telephone interface  100 ) and used as if it were a POTS/PSTN device rather than a cellular one. 
     There has been a growing trend of people “turning off” their subscriber-end POTS/PSTN service and questioning the cost of its installation and maintenance in new construction. The telephone interface  100  provides incentive based ways to at least slow this trend. Telephone service provider companies (TelCos) can keep POTS/PSTN phone lines installed but allow people to use cell phones in their homes or offices, potentially at a lower overall cost to the providers or the customers. Manufacturers can modify PBXs to allow cell phones  12   d  to operate through PBX systems, allowing cellular service providers and manufacturers to partner up with PBX manufacturers to allow the use of advance features in the telephone  12  as part of the PBX system. TelCos that provide POTS/PSTN but not cellular service especially have an incentive here, to have users keep existing POTS/PSTN live (subscribed to) and to install POTS/PSTN in new construction. Similarly, government entities have incentives here, to ensure there is telecommunications redundancy and to retain its existing levels of design and regulatory control. 
     Companies that provide non-telecommunications services also can have potential incentives here. For example, when there are device-area considerations. Without limitation, hotels, hospitals, alarm companies, and airports and airlines (in waiting and arrival areas, and on board aircraft) can benefit by providing their customers with telecommunications access via the customer&#39;s own telephones  12 . Hotels and hospitals are expected to provide telecommunications access, yet the conventional telephones they provide get little used and are costly to maintain. The same is the case for telephone handsets provided at every seat in passenger aircraft. 
     Airports are expected to provide pay-phones for the use of newly arrived travelers, but this particularly is costly as well as a source of customer service issues. As with most pay-phones, those in airports are subject to increased user abuse and outright vandalism. Airport pay-phones also have customer culture and payment considerations. Pay-phones with multi-language instructions are more costly, and still cannot address the language needs of every potential user. The features and the manners of usage of pay-phones also varies considerably by country or region. And then there is the matter of payments. In the United States, we are traditionally used to coin operated pay-phones. In some countries, e.g., Argentina, one purchases coin-like tokens at a shop or kiosk and then uses these in pay-phones, and in other countries, e.g., Japan, one purchases pre-paid calling cards from vending machines and all pay-phones accept these (exclusively, no coins of currency notes). In the U.S., airport staff are often asked by foreign visitors where they can buy tokens and phone cards. U.S. airports are also notorious for their lack of foreign exchange kiosks, and businesses at U.S. airport are almost as notorious for their rude responses to requests for coin change. 
     All of the above parade of horribles, as well as many others, can be avoided by businesses that provide telephone interfaces  100 . First, only the subscriber-side port  106   b  of the telephone interface  100  needs to be exposed, say as a conventional USB port, thus reducing the potential for damage and vandalism. In fact, if the subscriber-side channel  108  uses Bluetooth, WiFi, or ZigBee, nothing need be exposed. Second, instruction language and device feature concerns will be greatly reduced when users employ their own telephones  12  (e.g., cell phones, iPad™, etc.) Third, subscriber-provider protocol concerns can largely be eliminated, because the native protocol of the subscriber&#39;s telephone  12  (SIM card, CDMA, etc) is not relevant. Bluetooth and WiFi are standardized, and USB is close to standardized, so the subscriber-side port  106   b  of a telephone interface  100  can have sockets for all of the 5-6 most common USB plug types). Fourth, payment concerns will also be greatly reduced, since users can pay via one of their existing payment mechanisms. If a user uses a prepaid type cell phone  12   d , the charges can come from the prepaid amount. If a user is invoiced monthly by their cellular service provider, the charges can appear in their next invoice. If a user uses an iPad™ or Android™ tablet as their telephone  12 , and if it has payment for services set up (say, for downloading movies or music and charging these to a bank credit or debit card), then telephone charges can simply be included as well. Further, currency exchange transactions can easily be handled automatically, for instance, just as one can use a North American credit card to make purchases in Japan or use a North American debit card to withdraw Euros from ATM machines in Europe. And fifth, we come to user personalization. 
     Today, we enter huge amounts of data into smart instances of cell phones and other computerized devices. The phonebooks, contacts, and favorites entries in a smart cell phone or a tablet computer are common examples. Similarly, many of us extensively configure devices to better serve our needs and desires. The language of the user interface, particularized ring tones for different individuals or groups, and the uses of and accesses to call and location logging are common examples. Collectively we can term this “personalization.” 
     The telephone interface  100  permits us to significantly apply our personalization of telephones  12  more widely. All one needs to do with a personalization laden telephone  12  is connect it to a telephone interface  100  connected to a POTS/PSTN line, cable company, alarm company, or TelCo PBX (albeit, some of these will require minor modification), and one can employ their personalization. As just a few additional examples, a handicapped person can employ speaker phone features, sound volume or hearing aid interface settings, high contrast or color-blindness minimizing display preferences, etc. 
     Finally, returning to the example disaster scenarios, and in view of the present inventor&#39;s professional involvement in emergency services and management, it should be noted that the inventive telephone interface  100  can especially supplement or easily integrate with key Federal, State, local, and tribal government safety and critical infrastructure reliability programs, both in the United States and with foreign equivalents. 
     The 2003, 2008, and 2011 power outage examples discussed herein have not gone unnoticed by key officials. In the U.S., the Department of Homeland Security (DHS) as well as others concerned with emergency communications for crisis or emergency, attack and recovery and reconstitution are making substantial and ongoing preparedness efforts. The affects of the 2003 event on the Province of Ontario doubtless has similarly motivated Canada, and the affects of the 2011 event on the State of Baja del Sol doubtless has similarly motivated Mexico. 
     The U.S. Department of Homeland Security includes the National Communications System (NCS), which has multiple services that the present invention can coexist with or further the goals of. For instance, the NCS operates both the Wireless Priority Service (WPS) and the Government Emergency Telecommunications Service (GETS). 
     The Wireless Priority Service acknowledges our growing reliance on cellular networks, and that services in these networks can be “problematic” in national security and emergency situations. The WPS therefore provides priority for emergency calls made from some cellular telephones. The present invention supplements this, permitting the use of cell phones and similar devices (e.g., PDAs, tablets, etc.) when cellular service fails entirely. 
     As its name implies, the Government Emergency Telecommunications Service strives to maintain telecommunications between government entities. One of GETS&#39;s key programs is helping to establish Points of Contact (POCs) between government entities at all levels. Returning briefly to our hypothetical paramedic example, the regional disaster management center there is an example of such a POC and the ability of the paramedic to reach it with her personal cell phone  12   d  in the hypothetical disaster scenario there illustrates how the inventive telephone interface  100  can significantly further the goals of GETS. 
     In addition to furthering national efforts, however, the telephone interface  100  can assist in local efforts. Police and fire call boxes, blue tower/emergency phones, and even roadside emergency call boxes all can work with or be easily converted to work with the inventive telephone interface  100 . 
     For the above, and other, reasons, it is expected that the telephone interface  100  of the present invention will have widespread industrial applicability and it is therefore expected that the commercial utility of the present invention will be extensive and long lasting.