Automatic route selection

Abstract

An Automatic Route Selection (ARS) method and system for telephone calls. Routing is based upon a variety of factors using both digit analysis and table lookups. Calls are routed based on factors such as call type, call priority, and actual call costs defined in a rate table. With the present invention routing based on a variety of factors can be applied by the system administrator to achieve a cost efficient and cost-effective routing plan. An important factor that is used to route calls is the profile of the caller's history of usage. With a sliding window of recent calls, it is possible to estimate the expected hold time (duration) of a new call being placed in order to determine the most cost-effective route for that call.

Description

FIELD OF THE INVENTION

[0002] The present invention relates to communications systems and more particularly to telephone systems.

BACKGROUND OF THE INVENTION

[0003] Telephone switching is a well developed technology. Telephone switches are designed to route voice calls on a point to point basis. The technology for connecting computers into networks is also well developed. Computers networks such as local area networks (LANS) and wide area network (WANS) use packet routers and switches which are designed to route and switch data packets. Historically, the telephone systems and LANS in offices were entirely separate systems. Recently, there has been a growing tendency to integrate telephone systems and LANS. For example, co-pending patent application Ser. No. 09/527,968 filed Mar. 17, 2000 entitled “Integrated Scalable PBX and Router with Pooling” describe an integrated system that provides the functions of both a telephone PBX and an Ethernet data router. Systems such as that shown in co-pending application Ser. No. 09/527,968 include a programmable computer which allows one to route calls according to a stored program.

SUMMARY OF THE PRESENT INVENTION

[0004] The present invention provides Automatic Route Selection (ARS) for calls placed by a variety of users. Routing is based upon a variety of factors using both digit analysis and table lookups. Calls are routed based factors such as call type, call priority, and actual call costs defined in a rate table. With the present invention, routing based on a variety of factors, can be applied by the system administrator to achieve an efficient and cost-effective routing plan. An important factor that is used to determine the route of a particular call is a profile of a caller's history of usage. With a sliding window of recent calls to specific phone numbers, it is possible to estimate the expected hold time (duration) of a new call being placed in order to determine the most cost-effective route for that call.

DESCRIPTION OF FIGURES

[0005] FIG. 1 is an overall system diagram of a system utilizing the present invention.

[0006] FIG. 2 is a program flow diagram of the operation of the present invention.

[0007] FIG. 3 is a flow diagram of the program that determines the calling patterns of users.

[0008] FIG. 4A and 4B are a program flow diagram illustrating routing based upon a user profile.

[0009] FIGS. 5A and 5B are a program flow diagram illustrating routing based on priority.

DETAILED DESCRIPTION

[0010] In order to facilitate an explanation of the invention a number of terms will be defined. Many of the defined terms are terms of art regularly used in the telephone industry in connection with call accounting products. For example many of the terms given below are used in connection with a product known as “CommView” which is commercially marketed by the AtComm Corporation of Burlingame Calif. In the following description the following terms have the meaning given below:

[0011] Call Type—The call type is defined based on the jurisdiction of the call. After the breakup of AT&T in 1984 telephone call were classified calls into local carrier (LEC) and inter-exchange carrier (IXC) jurisdictions. The LEC's domain was defined within the Local Access Transport Area (LATA). The IXC's domain was defined as calls carried across LATA or state boundaries. These boundaries apply to the North American dialing plan only and are not applicable for international locations.

[0012] Within the LATA there are two classifications of calls: local and local toll. While most commercially marketed rate tables, such as those marketed by AtComm Corporation, rate both local and local toll calls, there is no call type distinction between the two (ie, both are call type 11). This is due to the variety of ways local calls are priced in different parts of the country. Some areas use a single flat-rate to price all local calls. Other areas use a mileage-based zone pricing scheme. Still other areas use a non-mileage-based zone pricing scheme.

[0013] Within the IXC's domain for domestic long-distance there are 4 classifications of calls: Interstate/InterLATA, Intrastate/InterLATA, Intrastate/IntraLATA, Interstate/IntraLATA. Other call types addressed for non-domestic calls are Canada, Puerto Rico and the Virgin Islands, and other international countries.

[0014] LEC—Local Exchange Carrier—The LEC is also known as the local telco or phone company. The Regional Bell Operating Companies (RBOCs) are the most common telcos in the US. These include Bell Atlantic (Nynex), Bell South, Ameritech, US West, SBC Communications (formerly PacTel and Southwestern Bell). Independent Operating Carriers (IOCs) and Competitive Local Exchange Carriers (CLECs) compete with the incumbent LECs.

[0015] IXC—Inter-exchange Carrier—Long distance carriers such as AT&T, Sprint, and MCI Worldcom.

[0016] Peak Hours—identifies the period of time during the 24-hour day when a carrier's “peak rates” apply. Typically, the peak time is assigned to the business day hours (8 am-5 pm). Off-Peak Hours—identifies the period of time during the 24-hour day when a carrier's “off-peak rates” apply. Typically, the off-peak time is assigned to the non-business day hours (5 pm-8 am).

[0017] Initial Peak Period—identifies the initial period of time used to measure the rate of a call carried during peak hour. Periods may be expressed in minutes (e.g., 1 min., 3 min.) or seconds (e.g., 60 secs., 6 secs.)

[0018] Overtime Peak Period—identifies the additional periods of time following the initial period used to measure the rate of a call carried during peak hour. Periods may be expressed in minutes (e.g., 1 min., 3 min.) or seconds (e.g., 60 secs., 6 secs.). Overtime periods are often, but not always shorter periods than the initial periods. As an example, the initial period may be 1 minute and the overtime period may be 6 seconds.

[0019] Initial Off-Peak Period—identifies the initial period of time used to measure the rate of a call carried during off-peak hour. Periods may be expressed in minutes (e.g., 1 min., 3 min.) or seconds (e.g., 60 secs., 6 secs.).

[0020] Overtime Peak Period—identifies the additional periods of time following the initial period used to measure the rate of a call carried during peak hour. Periods may be expressed in minutes (e.g., 1 min., 3 min.) or seconds (e.g., 60 secs., 6 secs.). Overtime periods are often, but not always shorter periods than the initial periods. As an example, the initial period may be 1 minute and the overtime period may be 6 seconds.

[0021] Rate Table—Commercially marketed proprietary information that contains rate information for a variety of carriers including the incumbent LEC and one or more IXCs. Rate tables are prepared by companies such as AtComm and delivered to call accounting customers in a variety of options. One common commercially used rate table format is designed for use with the AtComm product marketed under the name “CommView”. Rate tables are generally delivered to the customer via dial-up modem using secure authentication. Rates can also be delivered to customers over secure IP connections.

[0022] Time-Of-Day—(1) identifies the time of day a call occurred. This is referenced as the start time of the call; (2) TOD is sometimes used to refer to the call type (local, Interstate/InterLATA, etc.).

[0023] FIG. 1 is a block diagram of a first preferred embodiment of the present invention. As illustrated in FIG. 1, there are three main parts to the system. First, there is a variety of input-output devices or terminals 101, second there is a combined PBX and data router 102, and third, there are a variety of external networks 103.

[0024] The combined PBX data router 102 can for example be the system unit shown in co-pending application Ser. No. 09/527,968 filed Mar. 17, 2000 entitled “Integrated Scalable PBX and Router with Pooling”. Co-pending application Ser. No. 09/527,968 describes an integrated system that provides the functions of both a telephone PBX and an Ethernet data router. The content of co-pending application Ser. No. 09/527,968 is hereby incorporated herein by reference. Alternatively unit 102 can some other available programmable PBX. By providing a combined PBX and data router additional facilities are available to the system administrator. The present invention is implemented by computer programs 102B which are stored in unit 102.

[0025] The input-output devices 101 can be telephones connected to ports on unit 102 by normal telephone lines, computers connected to ports on unit 102 by LAN connections such as by Ethernet connections, or they can be other types of input-output units such as fax units connected to appropriate ports on unit 102. For convenience of illustration only four input devices 101A to 101Z are shown. In a typical system there would be many such input devices. For example a system with fifty such input-output devices would not be unusual.

[0026] The networks 103 are networks such as the conventional public switched network 103B, Internet network 103A which can handle data and Internet telephone calls, and private network 103C which can handle voice and data. Network 103B is connected to unit by 102 by connections such as trunk lines, T1 lines or other types on conventional telephone system connections. The Internet network 102A is the widely available Internet network which can be connected to unit 102 by a wide variety of available connections . Generally a connection to the Internet is through a commercial Internet Service Provider (ISP), many of which are available. Finally the system can be connected to a private data and voice network 103C. Such a connection would generally be through an Ethernet port on unit 102.

[0027] When the system receives a request from a user to place a call, the system has a wide variety of alternatives available. It can place the call over traditional telephone lines as is done with a conventional PBX or as a voice over IP call. The system can have a wide variety of different telephone services available via the public switched network. The task the present invention performs is to choose the most cost effective service consistent with other requirements for each call.

[0028] Each particular system will have a variety of alternatives available. One alternative is to send calls on a packetized basis over a data network as Voice over IP (VoIP). VoIP technology is known. These alternatives are established by a system administrator (from those available on the particular system) when the system is installed or at a later time. If one route is busy (fully occupied), the call can be sent over an alternative route. Route selection is based on a variety of factors including expected call length and the priority of the particular call.

[0029] Unit 102 is programmable and it includes programs 102B, a data base 102A which stores user and system information and a rate table 102C. Block flow diagram of programs 102B are given in FIGS. 2 to 5.

[0030] Programs 102B operate as follows: As indicated by block 201, the process begins when a user places a call or when the user sends a connection request via a computer terminal. Alternatively the connection request can be from another input-output unit such as a fax machine or video conference machine. Each unit 101 is connected to unit 102 via a particular port, hence, as indicated by block 202, when unit 102 receives a request it determines from its data base 102A, the characteristics of the unit that placed the request.

[0031] As indicated by block 203, each call is classified based upon the type of the call and the destination of the call. As indicated by block 204, data base 102A is interrogated in order to make this classification. As indicated by block 205, each call is assigned a class. The class of a call determines the type and quality of the service that will be provided. It also determines the priority for that call in relationship to other call types.

[0032] The least cost route is determined as indicated by block 208 and the call is routed as indicated by block 209. The route is determined by the class of the call and the profile of the user that made the call. For example, if a user usually makes very short calls to a particular dialed number, a route may be selected which measures calls in short increments, even though the cost per increment may be higher than other routes. On the other hand if a user usually makes long calls, a route with a low cost per increment will be selected even though the length of the increments may be longer.

[0033] The fact that it may be less expensive to select a route with a higher per second cost in certain situation is given below. The factor that must be considered in addition to the per second cost is the measurement increment. It should be understood that the numbers given below are merely an example and rate tables can provide a wide variety of alternatives. This following table provides a simple illustration.

	Length	Route of	Measurement	Cost per	Total
	of Call	Call	Increment	Minute	cost
Call A	1.5	Route 1	ten seconds	.03 cent	$1.89
	minute	Route 2	one minute	.02 cent	$3.60
Call B	5	Route 1	ten seconds	.03 cent	$9.00
	minutes	Route 2	one minute	.02 cent	$6.00

[0034] As illustrated about, for call A, route 1 is less expensive even though the per second cost is higher. Thus in routing a call, the expected length of the call is an important factor in determining the lowest cost route.

[0035] The rate table 102C can for example be the rate table which is commercially available from At Comm corporation and which is updated monthly on a subscription basis. In the case of the rate tables commercially available from Atcomm, rates are updated monthly on a server (the At Comm “CommView Server”) and are available for download to eligible customers at any time.

[0036] The program 102B requires three types of information in order to classify and route calls. The first type of information is the rate table information which is provided by table 102C. The second type of information is information about the nature of the input-output devices from data base 102A. The information about the various input-output devices can be loaded into the data base 102A by the system administrator or alternatively there are programs available that can automatically interrogate devices to determine this type of information.

[0037] The third type of information which program 102B needs is information about the typically calling patterns of users. FIG. 3 is a block diagram of a program for determining the typically calling patterns of users. This particular program detects a pattern in the last ten calls made by a user. Naturally various other techniques for detecting a pattern in the calls made by a user can be used in place of the relatively simple process illustrated in FIG. 3. The object of the program is to determine the expected length of calls by a particular user. In other embodiments, more complicated pattern can be determined.

[0038] The program begin as indicated by block 301, by assigning a default set of characteristics. That is, the user is assumed to have made ten calls having a length set to a default value. For example the default length could be five minutes. It is noted that a calling pattern can be determined by examining a certain number of calls. In the example illustrated in FIG. 3, a calling pattern is determined by examining the last ten calls made by a user. Initially all ten calls are set to a default value as indicated by block 301. Each time as call is made the oldest previous call is deleted and the characteristics of the new call replaces the deleted call as indicated by 303. The parameters for that user are then updated. In the example illustrated the parameter is the expected length of a call. In more complex situations the parameters calculated can be more complex. As shown in FIG. 3, calls to any number are grouped together. In other embodiments, the profile could be more granular. For example, a separate profile could be established for call to each particular telephone number, or to each area code, or to each group of area codes that is frequently called by the particular user. In still other embodiments, a separate profile is established for a group of frequently called area codes. The expected length of a call is calculated as indicated by block 302. After the user makes a call as indicated by block 303, the oldest previous value is reset to the more recent value as indicated by block 305. The expected length is then recalculated as indicated by block 308. The process is repeated when the user makes another call as indicated by block 303.

[0039] In general the technology is known for calculating various parameters from call history. For example see issued U.S. Pat. No. 6,185,145 which shows how patterns in calls can be calculated. The first embodiment of the present invention calculates the expected call length from the call history. It is noted that in alternative embodiments, additional factors used call routing can also be calculated from call history.

[0040] With the preferred embodiment of the present invention calls are divided into Priority-1 Routing and Priority-2 routing. It should be understood that each embodiment will have its own priority arrangement.

[0041] Priority-1 Routing is accepted as the top priority routing scheme for any calls offered to the switch matching criteria defined in this category. If the preferred Priority-1 route is not available, an optional attempt is made to route the call using the next matching Priority-1 route. If there are no more matching Priority-1 routes, an optional attempt is made to route the call using the first matching Priority-2 route, and so on.

[0042] Priority-1 routes are defined based on digits dialed. Priority-1 routes are expected to handle situations where carrier services have been assigned/contracted to handle specific types of calls. Examples of these types of calls are: ISDN BRI dialup connections to an ISP, Tie Lines (T1) to remote offices, or international calls handled under a special rating plan by a carrier different than the one used for domestic calls.

[0043] Priority-1 calls do not require any specific pricing information. They are identified based on the digits dialed by the person placing the call.

[0044] The Priority-1 table is limited to X number of table entries to be determined. A minimum of 64 entries is expected to be supported.

Trunk	Dial Access		Insert	Overflow
Group(s)	Code	Dialed Number	Digits	Permitted
Selected	Different dial	Any sequence of	This	Yes/No
from a list	access codes	digits following the	option	Selecting
of trunk	may be used	dial access code	allows the	“yes”
groups	to influence	such as:	adminis-	continues
available	the call	011 - any int'l call	trator to	search
to unit 102	routing.	01144 - any call to	identify	for next
in order of	Typically 9 is	UK	specific	Priority-1
prece-	used for PSTN	01144778 - any call	digits to	match if
dence.	calls. 8 or 7	to a specific city	be	circuit is
The defi-	for on-	in the UK	inserted	not
nition ex-	net/ESN calls.	1650 - any call to	into the	available.
ists to the	Numbers	area code 650	outpulsed	The last
granularity	dialed without	1650375 - any call	digits.	criteria
of trunk	an access	to the 375 prefix in	This	matched
group. If	code should	650	provides a	in
more than	be attempted	16503758188 - any	convenient	Priority-1
one circuit	to be	call to a different	and	may
is	completed as	office of the com-	flexible	overflow
available	station-to-	pany that owns the	way to	to
in the	station calls.	unit.	automate	Priority-2
trunk	In this case	375 - any call to the	remote	list under
group,	insert digits	local prefix 375	office DID	“yes”
Unit 102	option can still	3751111 - any call	speed	condition
hunts	be used to	to a local number	dialing,	and
based on	place a call	375xxxx - permits	routing to	circuit not
its	over the	wildcard to require	alternate	available
previously	PSTN.	7 digits dialed	equal
defined	The	where each last 4	access
hunt	administrator	digits can be any	carriers
algorithm	can define any	digit 0-9 - this may	(101xxxx)
for that	access codes	avoid conflicts be-	or other
group	as needed -	tween NPAs and	applica-
(terminal	the default	NXXs where 1+	tions.
or	access code is	dialing is not
circular).	9 for PSTN	required
	access.	Wildcard characters:
	Access codes	‘x’ - any digit 0-9
	should support	‘n’ - any digit 2-9
	at least 2-
	digits.

[0045] Priority-1 Routing Examples

	Dial
Trunk	Access	Dialed	Insert	Overflow
Group(s)	Code	Number	Digits	Permitted	Comment
Group 3 -	9	3128200		No	ISP access to
ISDN BRI					shared LAN
					Internet
					account over
					dialup
					BRI circuit.
Group 10 -		5xxx	16505	No	Implements a
MCI T1			48		convenient
					system-wide
					speed dial
					mechanism to
					call a remote
					office with
					exts. 5000-
					5999. Assumes
					a coordinated
					dialing plan
					between sites
					in the
					enterprise.
Group 13 -	21	011			Special Int'l
INTL A1					carrier group
					for special
					business calls
					to Pacific Rim
Group 11 -	9	011		Yes	All
AT&T T1					international
					calls are
					attempted to be
					carried by
					preferred
					carrier
					(AT&T). If all
					circuits are
					busy, other
					trunk groups
					may be used
Group 10 -	9	011		Yes	Alternate
MCI T1					carrier for int'l
					calls
Group 10 -	9	1		Yes	Preferred
MCI T1					carrier for
Group 11 -					domestic LD
AT&T T1					call (MCI),
					followed by
					alternate carrier
					(AT&T)
Group 10 -	9	nxxnxxx	1	Yes	Any 10-digit
MCI T1		xxx			number
Group 11 -					following
AT&T T1					NANP
					guidelines for
					LD matches
Group 2 -	9	1nxxnxx	10103	No	Default equal
PacBell CO		xxxx	21		access carrier
					for all
					domestic call
					types
Group 2 -	9	911		Yes
PacBell CO
Group 2 -		911		Yes	No dial access
PacBell CO					required for
					911
Group 2 -	9	nxxxxxx		No	All local traffic
PacBell CO					routed over
					LEC

[0046] Default Priority-1 Routing Table with BRI

[0047] If a BRI circuit is enabled, the user may elect to setup a table similar to the example below. This provides overflow for voice calls from the COTs to the BRI circuits if they are not in use for data.

[0048] Since no dialed numbers are defined in this example, all calls will be routed to the COT as first choice. This should be modified or deleted whenever a Priority-2 Table or Call Type Override Table is defined by the administrator to allow the Priority-2 table to select the proper least-cost route for each call.

	Dial
Trunk	Access	Dialed	Insert	Overflow
Group(s)	Code	Number	Digits	Permitted	Comment
Group 0 -	9			Yes	Default CO trunk
COT					group 0 for base
					unit's 4 CO circuits
					used for all inbound/
					outbound local +
					toll calls
Group 1 -	9			No	If BRI is available,
BRI					trunk group 1 can
					serve as overflow
					from group 0 as
					well as service data
					connections to ISP

[0049] Priority-2 Routing

[0050] Priority-2 Routing is a special application of call rating information that unit 102 has access to. This information is maintained as part of a subscription service that updates the rate table 102C. Unit 102 makes use of this same information to provide a least-cost reference which may be used in real-time to route offered call traffic. In addition to translating rate information maintained in the a rate table, users of system 102 can be provided with the option of adding their own rate definitions to be used in Priority-2 table lookups.

[0051] The Priority-2 Routing table is consulted if and only if all Priority-1 searches failed for any particular call being offered to the system. A single default entry always exists at the end of the Priority-2 table. This entry is defined as “DEFAULT CO OVERFLOW”. Its responsibility is to ensure that an attempt will always be made to carry any call offered to the switch through the CO trunk group serving the local exchange. It is important that unit 102 carry, rather than block calls, regardless of any programming errors made on the part of the administrator.

[0052] Custom Rates Plans can only be defined if a Rate Table which in included in the system allows the call type to be determined. This option allows the system adminstrator to define pricing that can be used to select the least-cost route for calls based on dialed digits. The rate plans defined by the administrator are used in addition to any other rate plans included in the Rate Table stored in the system.

Rate Plan	Call Types
User-defined name for this rate	Call types supported for this rate
table (tariff)	plan are defined by the Rate Table.
	The user enters 3 sets of
	information detailed below
	addressing these 3 call types:
	Intrastate, Interstate and
	International.
Peak Day Type	Peak Hours
Days types when peak	Defined as the hours during
rates may be applied:	which peak rates should be
Monday-Friday	applied for each type of
Saturday	day. Off-Peak Hours are
Sunday	defined by default as the
Holiday	other hours in the 24-hour
	period.
Initial Peak		Overtime Peak	Overtime Peak
Period	Initial Peak Rate	Period	Rate
Identifies the	Assigned as	Identifies the	Assigned as units
initial period	units (cents) as a	additional periods of	(cents) as a
of time used	floating decimal	time following the	floating decimal
to measure	(e.g., 0.655)	initial period used to	(e.g., 0.655)
the rate of a		measure the rate of
call carried		a call carried during
during peak		peak hour. Periods
hour.		should be expressed
Periods		in whole seconds
should be		(e.g., 60 secs., 6
expressed in		secs.). Overtime
whole		periods are often,
seconds		but not always
(e.g., 60		shorter periods than
secs., 6		the initial periods.
secs.)		As an example, the
		initial period may be
		60 seconds and the
		overtime period may
		be 6 seconds.
Initial Off-	Initial Off-Peak	Overtime Off-Peak	Overtime Off-
Peak Period	Rate	Period	Peak Rate
Identifies the	Assigned as	Identifies the ad-	Assigned as units
initial period	units (cents)	ditional periods of	(cents) as a float-
of time used	as a floating	time following the	ing decimal (e.g.,
to measure	decimal (e.g.,	initial period used to	0.655)
the rate of a	0.655)	measure the rate of
call carried		a call carried during
during off-		peak hour. Periods
peak hour.		should be expressed
Periods		in whole seconds
should be		(e.g., 60 secs., 6
expressed		secs.).
in whole		Overtime periods
seconds		are often, but not
(e.g., 60		always shorter
secs., 6		periods than the
secs.).		initial periods. As
		an example, the
		initial period may be
		60 seconds and the
		overtime period may
		be 6 seconds.

[0053]

Rate Plan	Call Type	Peak Day Type	Peak Hours
AT&T Custom	IntraState	Monday-Friday	8 am-5 pm
Tariff	(types 2, 3)	(Note: As a result
		these are
		automatically
		defined as
		off-peak):
		Saturday	12 am-11 pm
		Sunday	12 am-11 pm
		Holidays	12 am-11 pm
Initial Peak	Initial Peak	Overtime Peak	Overtime Peak
Period (secs)	Rate (cents)	Period	Rate
60	5	6	0.5
Initial Off-Peak	Initial Off-Peak	Overtime Off-	Overtime Off-Peak
Period	Rate	Peak Period	Rate
60	10	6	1
	Interstate	Monday-Friday	8 am-5 pm
	(types 1, 4)
Initial Peak	Initial Peak	Overtime Peak	Overtime Peak
Period (secs)	Rate (cents)	Period	Rate
60	10	6	1
Initial Off-Peak	Initial Off-Peak	Overtime Off-	Overtime Off-Peak
Period	Rate	Peak Period	Rate
60	15	6	1.5
	International	Monday-Friday	8 am-5 pm
	(types 8, 12-
	100)
Initial Peak	Initial Peak	Overtime Peak	Overtime Peak
Period (secs)	Rate (cents)	Period	Rate
60	25	6	2.5
Initial Off-Peak	Initial Off-Peak	Overtime Off-	Overtime Off-Peak
Period	Rate	Peak Period	Rate
60	25	6	2.5

[0054] The Priority-2 Routing table makes use of the rate information available from rate table 102C as well as any user-defined rates described in section 4.1 above. The search criteria for Priority-2 routing require tariffs supported by the user to be assigned to a hunt of one or more defined trunk groups.

[0055] The Priority-2 table is limited to X number of table entries to be determined by engineering. A minimum of 64 entries is expected to be supported.

		Intrastate	Interstate	Int'l.
	Associated Trunk	Discount	Discount	Discount
Rate Plan	Group(s)	Percentage	Percentage	Percentage
Initially	The trunk group	The user	The user	The user
provided or	associated with	may elect to	may elect	may elect to
user-defined	the rate table	enter a fixed	to enter a	enter a fixed
name for this	selected.	percentage	fixed per-	percentage
rate table	The list of avail-	discount for	centage	discount for
(tariff). This	able trunk groups	all intrastate	discount	all
is selected if	is based on the	calls for this	for all in-	international
evaluated as	logical groups de-	carrier rate	terstate	calls for this
the least cost	fined and avail-	plan. In this	calls for	carrier rate
route for the	able in data base	case, the rate	this carrier	plan. In this
call based on	102A. Any given	calculated by	rate plan.	case, the rate
the dialed	rate table may	program	In this	calculated by
number.	have more than	102B will be	case, the	program
The Rate	one associated	discounted	rate calcu-	102B ARS
Plan is	trunk groups. For	before com-	lated by	will be
matched in	example, A	parison to	program	discounted
union with	customer	other rates/	102B will	before
the Call	subscribing to the	plans	be dis-	comparison
Type. If	MCI Vision long	available.	counted	to other
either	distance plan may		before	rates/plans
matches, the	be carrying long		compari-	available.
associated	distance calls		son to
trunk group	over multiple		other
is selected.	MCI T1s. Each		rates/plans
Defining a	T1 would be de-		available.
Rate Plan in	fined as a unique
a table entry	logical trunk
does not re-	group. The MCI
quire a cor-	Vision rate table
responding	would then be as-
Call Type to	sociated to the
be defined.	collective group
	of T1s.

[0056] Priority-2 Routing Example—Note: this example does not assume that the Priority-1 Table example precedes it.

Rate Plan
Selected as		Intrastate	Interstate	Int'l.
Least Cost	Associated Trunk	Discount	Discount	Discount
Route	Group(s)	Percentage	Percentage	Percentage
MCI Vision	Trunk Group 9 -	8%	8%	15%
	MCI T1
	Trunk Group 10 -
	MCI T1
AT&T Custom	Trunk Group 11 -
Tariff	AT&T T1
Custom Tie	Trunk Group 15 -
Line	PacBell Tie Line
AT&T/LEC	Trunk Group 2 -
DDD	PacBell CO
	Trunk Group 2 -
	PacBell CO
	DEFAULT CO
	OVERFLOW -
	(This is the standard
	default to the CO
	trunk group for all
	call types -- user
	cannot remove or
	change this as last
	choice.)

[0057] Suggested Priority-2 Default Table

[0058] A setup wizard can be provided to assist the user in selecting tariffs available in the Rate Table 102C and associating them with trunk groups in the unit 102. The default table identifies overflow to the default CO group (Group 0—COT) for all local + toll calls.

Rate Plan
Selected as		Intrastate	Interstate	Intl.
Least Cost	Associated Trunk	Discount	Discount	Discount
Route	Group(s)	Percentage	Percentage	Percentage
	DEFAULT CO
	OVERFLOW -
	(This is the
	standard default to
	the CO trunk
	group for all call
	types -- user
	cannot remove or
	change this as last
	choice.)

[0059] Call Type Override

[0060] The Priority-2 table lookup must have the ability to be overridden by a simple call type lookup. The purpose of this table is to allow unit 102 to automatically recognize call types and route traffic accordingly. This can greatly simplify otherwise intricate data entry requirements such as discovering and entering all local prefixes. The Call Type Override requires the Rate Table 102C to be available in unit 102.

Call Type	Associated Trunk Group(s)
Select the call type from the list of possible	Select one or more trunk
call types:	groups to direct calls
1	Interstate/InterLATA	matching the call type
2	Intrastate/InterLATA	selected. The trunk list is
3	Intrastate/IntraLATA	prioritized top-down.
4	Interstate/IntraLATA
5	Canada
8	Puerto Rico
11	Local
12-19	Caribbean
20-100	International

[0061] Typically ARS programming tables on PBX equipment tend to become obsolete as soon as they have been entered or updated by the technician. Since January 1996, changes to the North American Dialing Plan have accelerated so that is difficult for any service organization to maintain coherent ARS tables in a PBX. With the trend continuing to drive negotiated tariff contracts to a postalized rating structure, one aspect of true cost reduction lies in the ability for the PBX to automatically distinguish between local calls, intrastate calls, interstate calls and international calls.

[0062] Companies that provide rate tables commercially are generally capable of automatically updating the national dialing plan information on a frequent (monthly) basis. New local prefixes, NPA splits and overlays, new Caribbean NPAs are all adjusted automatically in the PBX. This relieves the PBX service company and the administrator of the burden of trying to manually update the information.

[0063] Call Type Override is the simplest mechanism available to control call routing and reduce costs.

EXAMPLE

Call Type Override

[0064]

                     Associated Trunk
Call Type            Group(s)
Local (type 11)      Trunk Group 2 - PacBell
                     CO
Intrastate/IntraLATA Trunk Group 2 - PacBell
                     CO

[0065] Suggested Default Call Type Override

[0066] If Rate Table 102C exists in a system, the default call type override table should select the default CO trunk group 0 as the preferred route for all local and intrastate/intraLATA calls. Most long distance carrier plans do not provide any cost savings on local calls. The COT is the cheapest way to handle this. Mistakes in this programming on a PBX can cost the company in the range of 5 to 15 cents per minute, or more for every misrouted call.

                     Associated Trunk
Call Type            Group(s)
Local (type 11)      Group 0- COT
Intrastate/IntraLATA Group 0 - COT

[0067] Program 102B has the ability to present the administrator with breakdowns of calls placed to different locations (local, long-distance, int'l.) with actual costs accrued serves as another incentive for rate table subscriptions. The program 102B can also present the administrator with a detailed list of local prefixes (by zone if applicable) is a particularly useful incentive for some of the service providers and equipment providers. The details of the actual reporting program are conventional.

[0068] FIGS. 4A, 4B, 5A and 5B provide a more detailed program flow diagram of a program which implements the present invention on a programmable unit 102A.

[0069] As indicated by block 401, the process begins when a user places a request for a call. As indicated by block 402 the PBX captures all dialed digits terminated by ‘#’ or based on inter-digit timeout or submitted from user speed-dial list. Next as indicated by block 403 the PBX analyzes the dialed digits to determine the class of call, that is, the Call Type. Calls may be generally classified as internal station-to-station, On-Net VPN, Off-Net Public Network (local, local toll, long distance, international). Block 404 indicates that a check is made to determine if an authorization code is needed for the particular call. At system initialization or at some later time, the system administrator must store a list of calls needing authorization in data base 102A. As indicated by block 405 the PBX can identify the caller by the extension ID. It is noted that each extension is plugged into a different port on unit 102. Alternatively as indicated by block 496, the PBX can identify the caller by the authorization code. Either path leads to block 410 via block 409 and call permission is granted if appropriate.

[0070] Next as indicated by block 411 in FIG. 4B, The PBX queries the data base 102A for the user profile. This profile would have been previously generated as indicated in FIG. 3. Using the profile, the system calculates the estimated time for the call as indicated by block 412. The system then looks up Priority Routes for call in Priority Routing Tables based on Call Type as indicated by block 413. As indicated by block 414, the system calculates least cost route based on possible Priority Routes, Call Type and expected hold time for the call as a prioritized route list based on trunk groups available at that time. The system then sets up the call on the first available trunk or virtual circuit available in the selected Prioritized Route list as indicated by block 415. Finally the Call is attempted over the proper network (VPN, Public Network, Internet) and the process ends for that particular call.

[0071] FIGS. 5A and 5B are more detailed program block program flow diagrams showing how the system utilizes priority to route calls. The process begins as indicated by block 501 with the system, doing an analysis of the dialed digits including the dialed access code and the other dialed digits. As indicated by blocks 502 and 503, the system examines the rows in the priority-1 routing table until a match is found as indicated by block 504. Block 505 indicates that a check is made to determine if a circuit is available. If no circuit is available and overflow is not permitted as determined by block 506, the process proceeds to priority 2 routing block 509.

[0072] If a circuit is available a determination is made as to whether digit insertion is necessary as indicated by block 508. If digit insertion is necessary, the digits are inserted as indicated by block 507. The circuit is then selected as indicated by block 510.

[0073] The priority 2 routing process is illustrated in FIG. 5B. The call type is determined as indicated by block 511. As indicated by block 512, the estimated hold time is determined as previously explained. Blocks 513 and 516 indicate that the lines of the priority table are searched until a match is found as indicated by block 519. As indicated by block 514, the results table is sorted in order from the lowest cost to the highest cost. Blocks 515, 517 and 518 indicated that the result table is searched to find an available circuit. When an available circuit is found, the process ends as indicated by block 521.

[0074] With the present invention a call can be priced in real-time and this information can be sent to the end-user's telephone station during the call (for example via a related computer terminal). In this way, users would be apprised of actual call costs while on the phone.

[0075] It should be noted that while the embodiment of the invention described herein is implemented in the system shown in co-pending application Ser. No. 09/527,968, it should be understood that the invention can be applied to a wide variety of systems that include a programmable PBX. It should also be understood that the present invention can utilize the same principles to classify and route other types of requests for service. For examples, requests for transmission of data can be routed in a similar manner.

[0076] While the invention has been shown and explained with respect to preferred embodiments thereof, it should be understood that various changes in form and detail can be made without departing from the sprit and scope of the invention.

Claims

1) a method of routing telephone calls including the steps of: gathering information about the typical calling patterns of users, routing a call based upon both the typical calling pattern of the call's originator and data in a rate table that specifies the cost of routing calls along specific routes.

2) A system for routing telephone calls including means for gathering information about the typical calling patterns of users, means for routing a call based upon both the typical calling pattern of the call's originator and data in a rate table that specifies the cost of routing calls along specific routes.

3) A method of routing calls defined by dialed digits, said method placing calls based upon, an analysis of the dialed digits, the cost of the various available routes as specified by rate tables, and a profile of the user that placed the call whereby the anticipated length of the call is taken into account.

4) The method recited in claim 1 wherein said method includes the alternative of routing said calls via the Internet.

5) The method recited in claim 1 where the call pattern indicates the length of calls made.

6) The system recited in claim 2 wherein said system includes the alternative of routing call via the Internet.

7) The system recited in claim 2 wherein said calling pattern relates to the length of calls made by said caller.

8) The method of routing telephone calls comprising the steps of storing a rate table which indicates the cost of calls made using various routes, establishing the priority of various types of calls, determining the call pattern of the users that place calls, routing calls based upon a combination of the data in said rate table, the priority of a call and the call pattern of the user who placed the call.

9) A system for routing telephone calls comprising, a rate table which indicates the cost of calls made using various routes, a table which specifies the priority of various types of calls, a program for determining the call pattern of the users that place calls, a program analyzing the digits of a dialed call to establish the type of the call, and a program for routing calls based upon a combination of the data in said rate table, the priority of a call and the call pattern of the user who placed the call.

10) The method recited in claim 8 wherein said method includes the alternative of routing said calls via the Internet.

11) The method recited in claim 8 where the call pattern indicates the length of calls made.

12) A method of routing telephone calls comprising the steps of, analyzing the dialed digits to determine characteristics of the call, consulting a priority table to establishing a priority for the call, examining a profile of the callers past calls to establish an anticipated length of the call, and consulting a rate table based on the priority of the call and the anticipated length of the call to select a route for the call.