Telecommunications network circuit usage measurement

A system and method is provided for using underused or unused local telephone company local loops to subscriber premises for providing to such premises a connection to an alternate service provider. The use of the local loop is leased to the ultimate service provider at a rate dependent upon the usage and nature of usage of the circuit. Information and data to permit efficient and convenient billing for leased usage of the loops is implemented by providing on the local loop a passive monitor. The monitor detects and temporarily stores data relating to the commencement and termination of the signaling, the time of day, and the nature of the signaling that occurs. Data collected from the monitors is stored at a monitor center from which it is transferred to a billing operation such as the telephone company Revenue Accounting Office (RAO). Switching is provided to permit optional usage of the loop by either the telephone company of the alternate service provider or both. The use of a single local loop by multiple alternate service providers is also possible.

FIELD OF INVENTION 
This invention relates to the measurement of usage of specific portions of 
links in a telecommunications network and, more particularly, to a system 
and method for monitoring, detecting and measuring third party usage of 
predetermined links in a telecommunication network. 
BACKGROUND ART 
In the current communications environment multiple types of communication 
services and/or broadcasts are being provided to communication service 
customers over varying types of delivery links provided by different 
service providers. Telecommunications services are being provided to 
residences and businesses via the conventional loop and trunk circuits 
over which both voice and data are transmitted. At the present time the 
data transmissions over these circuits include facsimile, packet, imaging, 
and video content. 
U.S. Pat. No. 5,200,993, issued Apr. 6, 1993, to Wheeler et al., describes 
a public telephone network which includes enhanced capabilities with a 
distributed imaging system. The distributed imaging system provides 
centralized image processing to end users and access to a range of image 
management capabilities residing on a shared platform distributed through 
a switched telephone system. The shared platform functions as a service 
bureau in delivering such capabilities to end users. 
The distributed imaging system embodies an image platform based on the 
client-server model with standard communications interfaces to service 
multiple separate user groups accessing different applications. User 
groups can supply applications programs which are stored and run on the 
central hardware in support of respective user requirements. The image 
server operations are provided as functional primitives. User applications 
are provided by combining the primitives in a control script. 
U.S. Pat. No. 5,247,347, issued Sep. 21, 1993, to Litteral et al., 
describes a public switched telephone network architecture for providing 
video-on-demand services. A subscriber uses either a standard telephone 
instrument over the public switched telephone network or a dedicated 
control device over an ISDN packet network to order video programming. The 
request is transmitted to a designated video information provider and 
digital transmission connectivity is established between the video 
information provider and the central office serving the subscriber. 
Connectivity between the central office and subscriber is provided by 
asymmetrical digital subscriber line interface units over a local loop. 
The interface units frequency multiplex digital video information with 
voice information to the subscriber and support transmission of a reverse 
transmission channel from the subscriber to the central office for 
transmission on the ISDN packet data network back to the video information 
provider. The interfaces also allow baseband signaling and audio between 
the central office and the subscriber for conventional telephone 
instrument connectivity. 
U.S. Pat. No. 5,410,343, issued Apr. 25, 1995, to Coddington, et al., 
describes video-on-demand services using the public switched telephone 
network. In this system a central office based public switched telephone 
network is used for supplying video information from a digital information 
storage medium to designated subscriber premises. The system utilizes 
subscriber loop transmission means for transferring (1) selected video 
information from a central office to the subscriber premises, (2) 
subscriber order data from the subscriber premises to the central office 
location, and (3) telephone service signals between the subscriber 
premises and the central office. 
A switch at the central office receives the subscriber order data from the 
subscriber loop transmission means. A video gateway in turn is responsive 
to the subscriber order data from the switch for producing video routing 
data. A file server, responsive to requests received from the video 
gateway, obtains selected video information from the digital information 
storage medium. A cross-connect switch in turn is responsive to the video 
routing data for transmitting the video information from the file server 
to the subscriber loop transmission means. Asymmetrical digital subscriber 
line interface (ADSL) units over a local loop carry the necessary 
signaling between the subscribers and information providers. The interface 
units frequency multiplex digital video information with voice information 
to the subscriber and support transmission of a reverse control channel 
from the subscriber to the central office for transmission back to the 
information provider. 
U.S. Pat. Nos. 4,890,320 and 4,995,078, issued Dec. 26, 1989, and Feb. 19, 
1991, respectively, to Monslow et al., describe programming-on-demand and 
impulse pay-per-view delivery systems that utilize at least in part the 
public switched telephone network. These patents disclose a television 
broadcast system for real-time transmission of a viewer chosen program at 
a viewer requested time for the requesting viewer's television receiver. 
The system comprises a program collection, which stores TV programs on a 
video tape. Each program is assigned and labeled with a catalog number. A 
viewer request is transmitted using a conventional telephone over the 
public switched telephone network to a scheduling computer. The chosen 
program is transmitted at the requested time over a broadband cable for 
viewing on the requesting viewer's television receiver. A control unit 
prevents other households connected to the cable from viewing the program. 
U.S. Pat. No. 4,949,187, issued Aug. 14, 1990, to Cohen describes a video 
communications system comprising a remotely controlled central source of 
video and audio data. This system allows home viewers to select from a 
choice of movies or other video and audio data that may be transmitted 
from the central source to be stored at the viewer's premises. The viewer 
can play the selection at any convenient time of his choosing. The central 
source may store the data digitally. Movies that need to be frequently 
accessed are stored on disks. Movies that are accessed only infrequently 
are archived. A distribution system CPU controls the bi-directional flow 
of data from both types of drives. Several movies can be transmitted 
simultaneously to different viewers through a plurality of input/output 
controllers. To make use of a single transmission media, such as a 
telephone line, a multiplexer is used which may multiplex in the time 
domain or the frequency domain. 
U.S. Pat. No. 4,381,522, issued Apr. 26, 1983, to Lambert, discloses a 
cable television system which includes a plurality of selectable video 
signal sources having suitable television program material. The system 
enables a viewer to select desired program material available by telephone 
at a remote location and have the selected material promptly available for 
viewing. 
U.S. Pat. No. 4,888,638 issued Dec. 19, 1989, to Bohn, discloses a 
marketing research system for substituting stored TV programs for 
regularly scheduled, broadcast TV programs. The substitute TV programs may 
be transmitted from a central office via telephone lines to households of 
cooperating panelists for storage at the household premises. 
More recently, several different wideband digital distribution networks 
have been proposed for offering subscribers an array of video services, 
including true video-on-demand service. The following U.S. patents 
disclose representative examples of such digital video distribution 
networks: No. 5,253,275 to Yurt et al.; No. 5,132,992 to Yurt et al.; No. 
5,133,079 to Ballantyne et al.; No. 5,130,792 to Tindell et al.; No. 
5,057,932 to Lang; No. 4,963,995 to Lang; No. 4,949,187 to Cohen; No. 
5,027,400 to Baji et al. and No. 4,506,387 to Walter. 
A high percentage of television service to residential customers is now 
provided by coaxial cable delivery networks (CATV). CATV provides broad 
bandwidth and it is the expressed intention of cable television operators 
to provide local telephone service over their existing cables. At the same 
time, wireless or radio links are providing co-called wireless cable TV, 
as well as satellite delivery of television and data communication 
signals. In addition, the interexchange or long distance telephone 
carriers have expressed an intent to supply local connectivity for their 
interexchange services, thereby eliminating their need to connect through 
local exchange carriers and their local loop. 
In this competitive context it would seem probable that at least some 
existing local exchange carrier (LEC) local loops may become unused or 
under used. As a consequence it would be desirable and advantageous to 
LEC's to provide an alternate usage for such links and an effective and 
economical method for measuring usage for billing purposes. It is 
accordingly an object of the present invention to provide an arrangement 
and method for utilizing portions of the existing public switched 
telephone network for alternate purposes, while efficiently and 
conveniently providing a method of measuring the usage of such circuits 
for billing purposes. 
DISCLOSURE OF THE INVENTION 
According to the invention there is provided an arrangement wherein one or 
more telephone company local loops to subscriber premises may be utilized 
in whole or in part for providing to such premises a connection to the 
service platform of a third party alternate service provider. The 
alternate service provider may be another local telephone company, an 
interexchange carrier, a video service provider, a multi-media service 
provider, or the like. The use of the local loop is leased to the third 
party service provider at a rate dependent upon the usage and nature of 
usage of the circuit. 
Information and data to permit efficient and convenient billing for leased 
usage of such loops is implemented by providing on the local loop a 
passive monitor. The monitor detects and temporarily stores data relating 
to the commencement and termination of signaling, the time of day, and the 
nature of the signaling that occurs. Thus, charges may be dependent not 
only upon the time duration of signaling, but also on the rate of 
information transferred. 
Data collected from the monitors is stored at a monitor center from which 
it is transferred to a billing operation such as the telephone company 
Revenue Accounting Office (RAO). In the process of transfer of the 
information to the RAO it may be expedient to store the information in a 
convenient switch journal for transfer to the RAO over existing switch 
journal to RAO links. 
The data may be transferred from the monitors to the central storage 
through varying known procedures. The monitors are provided with 
identifying indicia, such as numbers, and are preferably provided with a 
buffer memory for temporarily storing data. The central storage includes a 
processor and can periodically sweep or scan the monitors to collect the 
data. Alternatively the monitors, which also include a microprocessor and 
clock, may periodically transmit or download their identification and data 
to the monitor center storage. As a still further alternative the monitors 
may download data on a real time basis. 
It is another feature of the invention that the monitors may be implemented 
as a part of a monitor-switch module. This module provides the option of 
connecting the local loop which extends to the customer premise to either 
the third party service provider or to an end office telephone company 
switch. This permits the possibility of part-time leasing of the loop or 
of simultaneous loop usage by the third party service provider and the 
telephone company. The latter usage is possible using non-interfering 
signaling modes by the two parties. Control of the necessary switching may 
be implemented without the necessity of additional wiring by using 
non-interfering in-band signaling. 
It is another feature of the invention that the link between the monitors 
and the monitor center for providing the monitor data to the monitor 
center may take multiple forms. According to one preferred embodiment of 
the invention, where a local loop is broken or disconnected remote from 
the end office or monitor center, the link to the monitor center may be 
provided by using that portion of the disconnected loop which formerly was 
connected to the switch for serving the telephone terminal in the customer 
premise. The other portion of the disconnected loop which extends to the 
customer premise is then connected to the alternate service provider's 
line to the service platform of such provider. The monitor is coupled to 
the loop at this location and the data connection of the monitor to the 
monitor center is made via the portion of the former local loop extending 
to the end office. As an alternative, separate links may be provided to 
connect the monitors to the monitor control center. As a still additional 
alternative, wireless or radio links may be utilized between the monitors 
and the monitor control center.

BEST MODE FOR CARRYING OUT THE INVENTION 
FIG. 1 is a simplified block diagram illustrating an arrangement to provide 
leased access to local loops in a switched telecommunications network to 
third party providers. The illustrated arrangement includes a system for 
monitoring, measuring and billing for such usage of the leased circuits on 
the basis of both the amount and nature of such usage. 
Referring to FIG. 1 there is shown an end office 10 of a local exchange 
carrier (LEC), which could be either a Regional Bell Operating Company 
(RBOC) or an independent telephone company which provides local telephone 
and related services. The LEC end office 10 typically includes a program 
controlled switch shown at 12. Such a switch may be a 5ESS switch 
manufactured by AT&T or equivalent switches available from other 
manufacturers. The switch 12 is connected by a suitable trunk 14 and 
tandem switch 16 to the telecommunications network indicated generally at 
18. In its original capacity as an LEC end office switch the switch 12 
provided connection to a series of local loops 20-36 connected to 
telephone terminals 38-54. It will be appreciated that these local loop 
connections are conventionally made and disconnected at the distribution 
frame. The frame is illustrated in FIGS. 2 and 4 but is not specifically 
shown in FIG. 1. The local loops have customer premise ends, which are 
connected to customer premise equipment (CPE), and telephone company 
(Telco) ends. The Telco ends normally terminate in the Telco central 
office which constitutes the end office for the loops. However, as further 
discussed herein, different sites for termination may be provided. The end 
office switch connections to the Telco ends of local loops are made via 
the distribution frame, which is also the terminus for the lines which 
make the actual switch connection. When a particular loop terminating at 
the distribution frame is disconnected from the switch, this disconnect 
commonly occurs via jumpers at the distribution frame. Thus local loop 
terminations at the central office remain on the distribution frame, as do 
switch connections. However, when the local loop terminations are 
disconnected from the switch connections at the distribution frame, this 
normally occurs by disconnecting the jumpers which formerly completed the 
connection. For convenience of illustration the local loops 20, 22 and 24 
are shown in the form of a cable 56 and the remaining local loops are 
shown as cables 58 and 60. 
According to the invention the local loops 26, 28 and 30, shown cabled at 
58, are leased to an alternate service provider A. Service provider A has 
a service platform 62 connected to the loops 26, 28 and 30 through an 
alternate service provider owned cable 64 to the LEC owned cable 58 which 
feeds the terminals 44, 46 and 48. The connection is made through a 
monitor 66. The connection through the monitor may be of a series nature 
such that the service provider signal passes through the monitor or, 
alternatively, the monitor may be inductively or otherwise coupled to the 
line carrying the service provider signal. 
The monitor shown as a single element at 66 actually comprises separate 
monitor units for each of the local loops 26, 28 and 30 for monitoring the 
individual usage of those loops, as presently described in greater detail. 
The individual monitor units in monitor 66 are connected via a data link 
or links 68 to a processor and storage 70. In similar fashion the local 
loops 32, 34 and 36 are connected through cable 60, monitor 72 and cable 
74 to yet another service provider B at that service provider's service 
platform 76. The monitor 72 again comprises three individual units for the 
separate loops 32, 34 and 36. These units are connected via a data link or 
links 78 to the monitor center processor and storage 70. 
Local loops 26-30 and 32-36 are leased to service providers A and B for 
charges based on usage and nature of usage, i.e., voice band, broadband, 
data rate, etc. It is anticipated that the lease agreements would identify 
the nature of usage intended and specify use rates for the particular type 
of service. This would permit the usage monitors indicated at 66 and 72 to 
be designed for measuring the intended usage. On the other hand, more 
universal monitors may be utilized if this should prove advantageous. 
The monitor units are connected by data links 68 and 78 to the processor 
and storage 70. This unit compiles a database of identified per loop 
cumulative usage by duration, time of day and nature of usage. For 
example, each monitor can mark the time of initiation of usage of its 
link, the time of day, the frequency, data rate, and bandwidth of use and 
the time of termination of that usage. The frequency, data rate and 
bandwidth utilized may change during usage and this is duly recorded in 
the processor and storage 70. The processor and storage 70 periodically 
formulate and transmit summary reports of link usage by customer to the 
switch journal 71 and from there to an appropriate billing entity such as 
the Revenue Accounting Office (RAO) 80. At the end of each month the 
records accounting office may compile and submit bills to the respective 
customers for their usage of the leased links. 
Referring to the left-most illustrative telephone terminals 38-42 served by 
the LEC end office switch 12, this set of loops is shown connected to the 
switch 12. However, the loops may also be leased on a full or part-time 
basis to an alternate service provider. When the loops 20-24 are served by 
the LEC switch 12, the cable 56 is connected to the switch at 82. However, 
the cable 56 is connected to cable 82 through a combined monitor and 
switching module 84 described in detail hereinafter in connection with 
FIG. 3. The monitor in the combined module 84 provides a connection 86 to 
a the third alternate service provider C at that provider's service 
platform 88. The switch and monitor module 84 is also connected via data 
link 90 to the processor and storage unit 70. 
This arrangement provides several options. The LEC may provide plain old 
telephone service (POTS) to the telephone terminals 38-42, while granting 
to the service provider C a lease to use the local loops 20-24 for 
non-conflicting or non-interfering service. Such service may be in a 
frequency band separated from the conventional 4,000 KHz band utilized by 
the voice signal. That service usage can be monitored via the monitor unit 
84 and billed by the RAO as previously described. At the same time the LEC 
may provide its own POTS service to one or more of the terminals 38-42. It 
will be understood that simultaneous service by the third party alternate 
service provider terminates in a terminal other than the POTS or other 
telephone served by the LEC. Such a terminal may be a video, facsimile, 
printer, or the like. The monitor module 84 contains separate sub-units 
for the individual loops 20-24 as previously described. 
Alternatively to the foregoing, service provider C may lease one or more of 
the loops 20-24 on an as needed basis at such times as the loop can be 
seized in an on-hook condition. As a still further alternative, service 
provider C may choose to lease the entire capacity of the loops either on 
a demand basis or at specified times of day. In this situation the loops 
are disconnected from the switch during the time of use by the alternate 
service provider. A central office controlled switch may be provided at or 
adjacent to the switch 12 for this purpose. 
Referring to FIG. 2 there is shown another preferred embodiment of the 
invention. While the connections between the alternate service providers 
and the local loops are shown as being made within an LEC end office in 
the embodiment in FIG. 1, it is not necessary that these connections be 
concentrated. In FIG. 2 there is shown an embodiment of the invention 
wherein alternate service providers connect to their leased local loops at 
distributed sites. In this embodiment a monitor center 100 may be located 
at any convenient site. The monitor center houses the processor and 
storage 102 which is connected to the revenue accounting office (RAO) 104 
via a suitable link 105. 
The processor and storage 102 is connected by a data link or links 106 to a 
connection or distribution frame 108 for connection to the monitor leads 
110-126. These monitor leads in turn are connected to outdoor mounted 
monitors 128-132, vault mounted monitors 134-138, and monitor center 
mounted monitors 140-144. The monitor center monitors 140-144 constitute 
the individual monitors in a monitor module such as the monitor module 84 
in FIG. 1 and the module 300 illustrated in FIG. 3, presently to be 
described. These units perform both monitor and switching functions. 
Monitors 140-144 are connected to the distribution frame 108 not only by 
data links 122-126 shown with broken lines, but also by local loop lines 
shown as solid lines at 146-150. These local loop lines provide connection 
through the monitor-switch units 140-144 to the outdoor local loops 
152-156 which terminate at telephone terminals 158-162. The local loops 
152-156 are connected through the distribution frame 108 to lines 164-168 
to the LEC end office switch 170. The switch 170 in turn is connected to 
the switched telephone network indicated generally at 172. 
The second set of monitors 134-138 is not mounted in the monitor center 100 
but in an externally located site 214. Monitors 134-138 connect local 
loops 174-178 to service provider D at 206 via lines 208-212. By way of 
example, the monitors 134-138 may be housed in a controlled environmental 
vault (CEV) 214. The monitors 134-138 are connected to the distribution 
frame 108 by loop lines 116-120. 
The third group of monitors 128-132 is outdoor mounted and may be overhead, 
pedestal or otherwise mounted. The local loops 186-190 connect the 
premises housing telephone terminals 192-196 to alternate service provider 
E. The monitors 128-132 may be exterior units mounted singly or in 
clusters on overhead structures. 
It is a feature of the invention that the monitor connections to the 
distribution frame 108 may be made through the use of the conductors which 
previously served as portions of the local loops from the end office 
switch serving the original telephone terminals. This is particularly 
applicable to the outdoor monitors 128-132 and the CEV monitors 134-138. 
This use of the disconnected local loop leads facilitates implementation 
of distributed connections to the alternate service providers and 
distributed monitoring. When this is done there is no need to locate or 
install separate monitor data collector leads from the monitors to a 
monitor center. The installation is facilitated in that the technician 
making the monitor connection needs only to break the existing local loop, 
connect the telephone terminal end to the alternate service provider, and 
connect the former switch end to the data terminals on the monitor. The 
monitor is either inductively coupled to the leased loop portion, inserted 
in series therewith, or bridged onto that portion of the local loop. The 
monitor center may conveniently be sited proximate an LEC network 
switching office for ready connection to the network. 
It is possible to use these existing local loop leads which are now 
connected to the monitor center to serve combination monitor-switch 
modules such as units 140-144 by conducting the necessary switch control 
via in-band signaling over the loop. Such signaling may be used not only 
from the monitors to the processor and storage 102 but also over the 
connection to the alternate service providers. This permits the alternate 
service providers to also maintain a running compilation of individual 
line usage where this is desired. 
Referring to FIG. 3 there is shown a simplified block diagram of an 
illustrative monitor-switch module which may be used in the system of the 
invention. The monitor-switch module 300 is connected to its alternate 
service provider at 302, to the LEC end office at 304, and to the external 
loop and customer premise terminal at 306. The service provider connection 
at 302 continues in module 300 as line 308. Line 308 is connected to a 
bypass switch module which comprises a switch 310 and a switch control 
312. The switch control and switch are also connected to the LEC line 304 
which goes to the LEC switch (not shown), and to the customer terminal 
line 306 and to the local loop to which it is connected. 
When the local loop 306 is leased by the service provider on a full time 
basis the switch 310 connects the terminal and loop line 306 directly to 
the incoming service provider line 308. The terminal and loop line 306 are 
then disconnected from the LEC switch line 304. If the contrary situation 
exists where the LEC is serving the loop and telephone terminal on a full 
time basis, the converse is true. The loop 306 is then directly connected 
to the LEC line 304 and is disconnected from the service provider lines 
308 and 302. 
The condition of the switch 310 may be controlled by the LEC by in band 
signaling to the switch control 312 over the line 304. If desired, the LEC 
may provide for shared usage of the loop 306 and permit the service 
provider 302 the ability to control the switch by similar inband signaling 
over the service provider line 308. A contention situation may exist at 
the switch 310 which may be handled by conventional busy signal protocols 
or a similar arrangement. The agreement between the LEC and the alternate 
service provider may obviously establish the conditions for solving such 
contention situations. The availability of this type of switching can also 
be used to permit the service provider access to the LEC switched network 
under agreed conditions. 
The monitor module 300 also contains a microprocessor 314, clock 316, 
storage 318, signal analyzer 320, and interface and transmitter or modem 
322. The microprocessor controls the signal analyzer, storage and 
transmitter or modem. The signal analyzer 320 is connected to the incoming 
service provider signal via connection 321 and provides an output which 
indicates the presence or absence of a service provider signal, the nature 
of the signal, the baud rate or rate of information transfer, and other 
details of the signal where desired. Such analyzers are well known in the 
art and in an illustrative embodiment may take the form of the analyzer 
manufactured by Advanced Electronic Applications, Inc. under their model 
number PK-232MBX. 
The output of the signal analyzer 320 is periodically connected to the 
storage 318 under control of the microprocessor and such output is 
recorded along with the time of each entry. This provides in the storage 
318 a database of usage which shows the time and duration of usage and the 
nature of the signal or signals being carried. This data is periodically 
transferred to the processor and storage 70 or 102 of the LEC for billing 
purposes as previously described in connection with FIGS. 1 and 2. 
It is also a feature of the invention that billing information may be 
supplied directly to the service provider for purposes of the service 
provider billing its own customers. Such billing information may be 
supplied by the LEC either from the RAO via the telephone network or, as 
an alternative, the microprocessor in the monitor may be programmed to 
effect a connection from the transmitter or modem 322 to the providers 
line 308 through the switch 310 for transfer direct to the service 
provider by suitable signaling over that line. If desired by the service 
provider the monitor may also be arranged to monitor the identity of the 
channel being delivered to the subscriber over the loop. If such a feature 
is desired the monitor may be provided with the added feature of making 
such an identification in the manner shown by way of example in the 
monitor described in U.S. Pat. No. 4,893,248, issued Jan. 9, 1990 to Pitts 
et al. 
Referring to FIG. 4 there is shown yet another embodiment of the invention 
wherein the link between the monitors and the monitor center is provided 
in a wireless fashion by a suitable radio connection. FIG. 4 shows an 
embodiment of the invention similar to that shown in FIG. 2 with the 
exception of the link provided between the monitors 128-132 for service 
provider E and the monitor center 100. According to this feature of the 
invention the data connection to the monitors 128-132 is fed via lines 
400, 402 and 404 to a suitable multiplexer, modulator and transmitter 406. 
An antenna 408 radiates the modulated carrier, preferably at a frequency 
in the VHF band or above. This signal is received by a receiving antenna 
410 of a receiver, demodulator and demultiplexer 412. From the unit 412 
the demultiplexed signals are fed via leads 414, 416 and 418 to the 
distribution frame 108 and from there via the link 106 to the processor 
and storage 102. The transmitter, modulator, multiplexer and receiver, 
demodulator and demultiplexer may be of any suitable type well known to 
those skilled in the art and may, for example, be of the type described in 
detail in U.S. patent application Ser. No. 08/405,685 filed Mar. 17, 1995, 
and co-assigned with the present invention. 
It will be readily seen by one of ordinary skill in the art that the 
present invention fulfills all of the objects set forth above. After 
reading the foregoing specification, one of ordinary skill will be able to 
effect various changes, substitutions of equivalents and various other 
aspects of the invention as broadly disclosed herein. It is therefore 
intended that the protection granted hereon be limited only by the 
definition contained in the appended claims and equivalents thereof.