Multiple independent named call-coverage paths

An improved call-coverage arrangement (106) allows a principal (120) to program (administer) and name multiple independent call-coverage paths (211) for the principal's telephone number. Selection of an individual call-coverage path for an individual call to the principal's telephone number depends either on which one of the call-coverage path is active (221) or on which one of the call-coverage path's selection criteria (212) are matched by the parameters of the call. The selection criteria are likewise programmable by the principal. The principal remembers and accesses (for administration) individual call-coverage paths by name (220).

TECHNICAL FIELD 
This invention relates to telecommunications user features. 
BACKGROUND OF THE INVENTION 
Call coverage is a call-redirection feature that provides for a plurality 
of alternative-destination telephone numbers (or other addresses) to which 
the telecommunications system can sequentially try to deliver a call (or 
other communication) intended for a principal telephone number when the 
call cannot be delivered to the principal telephone number or when the 
principal elects to not receive the call at the principal telephone 
number. 
Unlike call forwarding, which is a call-redirection feature that provides a 
single alternative-destination telephone number for calls to the 
principal, call coverage has not been user-programmable. That is, the 
principal could not program his or her own call-coverage path, but had to 
rely on an administrator of the telecommunications system to do so. This 
has changed with the introduction of the AT&T True Connections.RTM. 
service. The call sequencing feature of this service allows a principal to 
program his or her own call-coverage path (called a reach list). 
Conventional telecommunications systems allow for one call-coverage path 
for each telephone number served by the system (i.e., for each extension 
number). A principal may have a plurality of extension numbers, and to 
that extent may have a plurality of call-coverage paths. The AT&T 
Definity.RTM. G3V2 private branch exchange (PBX) provides a capability of 
linking these separate call-coverage paths into a single long 
call-coverage path that is common to the plurality of the principal's 
extension numbers. 
SUMMARY OF THE INVENTION 
In accordance with the principles of this invention, an advance is made 
over the prior art by providing for multiple independent, preferably 
user-programmable, coverage paths at least one of which may be active at 
any one time, and further by providing for user naming of the coverage 
paths to facilitate the user's recognition of, and differentiation 
between, the multiple paths. 
According to one aspect of the invention, a telecommunications system 
includes a memory, associated with a principal address (e.g., a principal 
telephone number) for receiving communications (e.g., calls), that stores 
information defining a plurality of independent coverage paths for the 
principal address, wherein each coverage path comprises a plurality of 
alternative addresses for receiving a communication directed to the 
principal address. In response to receipt of a communication directed to 
the principal address, the system selects one of the plurality of coverage 
paths, and redirects the communication to an alternative address included 
in the selected coverage path. Illustratively, the stored call coverage 
information either indicates which of the coverage paths is active or 
includes criteria for selecting each coverage path, and the system selects 
either the one of the plurality of coverage paths that is active, or the 
one of the plurality of coverage paths whose criteria are satisfied by the 
call. The principal address is assigned to a principal as the address of 
communications intended for the principal, and the information defining 
the plurality of independent coverage paths is preferably programmable by 
the principal. The information defining the plurality of independent 
coverage paths preferably includes, for each coverage path, a different 
name given to the coverage path by the principal. The name is likewise 
programmable by the principal. In response to receipt from the principal 
of one of the names, the system gives the principal access to the stored 
information defining the coverage path having that name. 
According to another aspect of the invention, a method of providing 
coverage for a communication directed to a principal address comprises the 
following steps. In response to receipt of the communication directed to 
the principal address, a coverage path for the communication is selected 
from a plurality of independent coverage paths that are defined for the 
principal address. Each defined coverage path comprises a plurality of 
alternative addresses for receiving the communication directed to the 
principal address. In response to the selection, the communication is 
redirected to an alternative address included in the selected coverage 
path. Preferably, the principal names the coverage paths, and programs 
their definitions including their names. The principal then accesses the 
definitions of individual paths by the path names. 
We have recognized that a user's call-coverage needs may change over time 
due to various conditions. User programmability of coverage paths gives 
direct control to the user to change their coverage paths as their need 
changes, rather than having to go through a central administrator who may 
not be able to meet the user's changing needs in a timely manner. 
We have also recognized that a user may need different call-coverage paths 
for different situations. For example, a user may wish to implement 
time-of-day dependency into his or her call-redirection, wherein one 
call-coverage path is active during working hours, but another 
call-coverage path is active during the evening and night and on weekends. 
Multiple call-coverage paths provide the user with the ability to set up 
different call-coverage paths for the different situations. The user then 
simply activates the coverage path that is appropriate for the present 
situation, without having to reprogram each coverage path each time that 
it is needed. Alternatively, the user may have a plurality of paths 
active, and simply specify to the system the selection criteria for 
selecting one or another of the paths. For example, the user may specify 
that one call-coverage path be used for inside calls (ones originating 
from other extension numbers of the system) and that another call-coverage 
path be used for outside calls. 
Finally, we have recognized that, in a multiple call-coverage path 
environment, a user needs an easy way to identify individual paths and to 
differentiate between them. User naming of coverage paths allows the user 
to associate a different meaningful and easily-recognizable tag--a 
name--with each path. This provides the user with an easy way to denote, 
describe, renumber, and recognize each path. For example, meaningful tags 
for the call paths of time-of-day scenario presented above may be "9-to-5" 
and "off-hours", and for the inside/outside call-origination scenario may 
be "internal calls" and "external calls". 
These and other advantages and features of the present invention will 
become more apparent from the following description of an illustrative 
embodiment of the invention taken together with the drawing.

DETAILED DESCRIPTION 
FIG. 1 shows an illustrative telecommunications system. It includes a 
plurality of telecommunications endpoints 100-102 coupled by endpoint 
interfaces 103 to a switching fabric 104 which selectively interconnects 
endpoints 100-102 with each other under control of a telecommunications 
controller 106. Switching fabric 104 also selectively connects endpoints 
100-102 via gateway interfaces 105 to an external telecommunications 
network 109 and therethrough to endpoints 107-108 served by network 109. 
Telecommunications controller 106 is a stored-program-controlled machine 
that includes a memory 112 for storing control programs 113 and control 
data including a translations database 114, a processor 111 that executes 
control programs 113 and uses control data including translations database 
114 to control switching fabric 104, and an interface 110 to switching 
fabric 104 through which processor 111 communicates with switching fabric 
104 and other entities of the system of FIG. 1. 
As described so far, the telecommunications system of FIG. 1 is 
conventional. In one embodiment, elements 103-106 comprise a telephony 
switching system such as the AT&T Definity.RTM. PBX, endpoints 100-101 and 
107-108 comprise telephones, fax machines, data terminals, etc., VMS 102 
comprises the AT&T Intuity.RTM. multimedia messaging system, and network 
109 comprises the public or a private telecommunications network. In 
another embodiment, telecommunications controller 106 comprises the AT&T 
MMCX multimedia communications exchange, switching fabric 104 comprises a 
local area network (LAN), interfaces 103 and 105 comprise LAN interfaces, 
endpoints 100-101 and 107-108 comprise multimedia workstations, VMS 102 
comprises the AT&T Intuity.RTM. multimedia messaging system, and network 
109 comprises a wide area network (WAN) or the public telecommunications 
network. 
According to an illustrative embodiment of the invention and as shown in 
FIG. 2, translations database 114 includes sets of translations 200-201, 
one for each principal address (e.g., extension number) served by 
communications controller 106, each of which provides for definitions of a 
plurality of call-coverage paths 211. Each definition of a call-coverage 
path 211 includes a path name 220, a status (active or inactive) indicator 
221, a criteria list 222 that specifies the criteria for determining when 
to use this call-coverage path, and a sequence of addresses (e.g., 
telephone numbers) 223-224 that make up this call-coverage path. The 
call-coverage data of each set of translations 200-201 further include a 
call-coverage status 210 that indicates whether the call-coverage feature 
is or is not activated for the corresponding principal address. Further 
according to the illustrative embodiment of the invention, control 
programs 113 of telecommunications controller 106 include a 
call-coverage-path administration program and a call-coverage 
call-processing program, whose functionalities are respectively shown in 
FIGS. 3 and 4. 
As shown in FIG. 3, a principal or another user 120 who wishes to 
administer a call-coverage path logs into telecommunications controller 
106 through one of the endpoints 100-101 or 107-108, at step 300, selects 
call-coverage path administration from an activities menu, at step 302, 
and provides the principal address (extension number) whose call-coverage 
he or she wishes to administer, at step 304. In the case of 
telecommunications controller 106 being the AT&T Definity PBX, the user is 
presented with a Touch-Tone signaling interface for administering the 
call-coverage feature. In the case of telecommunications controller 106 
being the AT&T MMCX exchange, the user is presented with a graphical-user 
interface (GUI), such as the one shown in FIG. 5, for administering the 
call-coverage feature. In response, controller 106 checks translations 200 
of the principal address to determine whether it has one or more 
call-coverage paths 211 specified, at step 306, and informs the user 
accordingly, at step 308 or 310. In the case of the Touch-Tone signaling 
interface, the user is informed via played-back announcements. In the case 
of the GUI interface, the user is presented either with a blank window of 
FIG. 5, at step 308, or with the window of FIG. 5 populated with the 
existing call-coverage data, at step 310. The user then provides a 
call-coverage path name by which he or she refers to, and remembers, a 
particular call-coverage path, at step 312. In response, controller 106 
checks whether a call-coverage path 211 of that pathname 220 already 
exists in the address' translations 200, at step 314, and if so, presents 
that path 211 to the user, at step 316. In the case of the Touch-Tone 
interface, the addresses that make up the coverage path are announced to 
the user; in the case of the GUI interface, they are displayed in the 
"Coverage Points" area of the window of FIG. 5. Following step 316, or if 
a path of that name is not found to exist at step 314, the user provides 
data to program or reprogram entries 221 and 223-224 of the path 211, at 
step 318. If the system allows for multiple active paths, as indicated at 
step 320, the user is also asked to provide criteria 222 defining when 
this path is to be used, at step 322. In the case of the Touch-Tone 
interface, this is done via a played-back announcement; in the case of the 
GUI interface, the user is presented with a window such as the one shown 
in FIG. 6. If multiple active paths are not allowed, or after the user 
provides the path-use criteria at step 324, controller 106 validates all 
of the information that was entered by the user, at step 326. For example, 
controller 106 checks that all path names for this principal address are 
unique, that all addresses of coverage points are valid, and that path-use 
criteria of multiple call-coverage paths for this principal address do not 
conflict with each other. If any of the call-coverage information for this 
principal address is invalid, as determined at step 328, controller 106 
informs the user, at step 330. Upon receiving a correction from the user, 
at step 332, controller 106 repeats the validation, at step 326. When the 
call-coverage information for this principal address is determined to be 
valid at step 328, controller 106 enters the information provided by the 
user at steps 304, 312, 318, and 324 in fields 220-224 of the subject path 
211, at step 334. If the user is not done administering call paths, as 
determined at step 336, the system returns to step 312 to administer 
another call path 211; if the user is done, call-path administration ends, 
at step 338. 
As shown in FIG. 4, when a call comes in for a principal address, at step 
400, a call-processing function of controller 106 determines in a 
conventional manner if unconditional call redirection is active for this 
address (e.g., the user of the endpoint that corresponds to the address 
has pushed a "send-all-calls" button), at step 402. If unconditional call 
redirection is not active, controller 106 conventionally attempts to 
connect the call to the principal address, and if the attempt succeeds, as 
determined at step 404, the call is handled conventionally, at step 408. 
However, if the attempt fails (for example, because the endpoint of the 
principal address is busy or does not answer), of if it has been 
determined at step 402 that unconditional redirection is active, 
controller 106 checks call-coverage status 220 of the principal address' 
translations 200, at step 406. If call coverage is not enabled, controller 
106 handles the call conventionally, at step 408. If call coverage is 
enabled, further call-coverage processing depends on whether multiple 
active call-coverage paths are allowed, as indicated at step 410. If 
multiple active paths are not allowed, the call-processing function of 
controller 106 examines status indicators 221 of all paths 211 of the 
principal number and selects the active path 211, at step 412. If multiple 
active paths are allowed, the call-processing function of controller 106 
attempts to match parameters of the incoming call against criteria 222 of 
all paths 211 of the principal number whose status indicators 221 indicate 
that they are active, at step 414, and selects the matching path, at step 
416. One of the paths 211 may have criteria 222 of "default", which result 
in the selection of this path 211 when the criteria 222 of no other paths 
211 match the call parameters. Following step 412 or 416, the 
call-processing function of controller 106 uses the selected one path 211 
in a conventional manner to provide call-coverage to the incoming call, at 
step 418. 
Of course, various changes and modifications to the illustrative embodiment 
described above will be apparent to those skilled in the art. These 
changes and modifications can be made without departing from the spirit 
and the scope of the invention and without diminishing its attendant 
advantages. It is therefore intended that such changes and modifications 
be covered by the following claims.