U.S. patent application number 09/908813 was filed with the patent office on 2001-11-15 for extended number portability database services.
Invention is credited to Madour, Lila, Sultana, Shabnam.
Application Number | 20010040958 09/908813 |
Document ID | / |
Family ID | 22826634 |
Filed Date | 2001-11-15 |
United States Patent
Application |
20010040958 |
Kind Code |
A1 |
Madour, Lila ; et
al. |
November 15, 2001 |
Extended number portability database services
Abstract
A system and method for providing portability of internet
addressing maintains additional IP addressing information in number
portability databases located throughout provider domains in a
telecommunications network. This additional IP addressing
information, in conjunction with additional Number Portability
Request messaging information, permits portability of addresses
across telecommunication and data communication networks in a
transparent fashion.
Inventors: |
Madour, Lila; (Kista,
SE) ; Sultana, Shabnam; (Kista, SE) |
Correspondence
Address: |
Ronald L. Grudziecki
BURNS, DOANE, SWECKER & MATHIS, L.L.P.
P.O. Box 1404
Alexandria
VA
22313-1404
US
|
Family ID: |
22826634 |
Appl. No.: |
09/908813 |
Filed: |
July 20, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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09908813 |
Jul 20, 2001 |
|
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09221165 |
Dec 28, 1998 |
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Current U.S.
Class: |
379/221.14 ;
379/207.02 |
Current CPC
Class: |
Y10S 379/90 20130101;
H04L 9/40 20220501; H04L 61/00 20130101; H04L 61/45 20220501; H04Q
3/005 20130101 |
Class at
Publication: |
379/221.14 ;
379/207.02 |
International
Class: |
H04M 003/42; H04M
007/00 |
Claims
What is claimed is:
1. A method of routing calls through a communications network
comprising the steps of: a) initiating a call from a first
subscriber in a call-originating domain to a second subscriber in a
data communications domain; b) transmitting a first message from a
first node in said call-originating domain to a database in said
call-originating domain; c) locating a current data communication
network node parameter in said database, wherein said network node
parameter is associated with said second subscriber; d)
transmitting a second message that includes said located data
communication network node parameter from said database to said
first node; e) routing said call from said first node to a data
communications address indicated by said located data communication
network node parameter; and f) updating said database when said
second subscriber changes membership from a first communication
network provider to a data communication network provider.
2. The method of claim 1, wherein step c) further comprises the
substep of: i) converting said located data communication network
node parameter to a data communications address using a naming
address database.
3. The method of claim 1, wherein the network node parameter is an
IP address.
4. The method of claim 2, wherein the data communications address
is an IP address.
5. The method of claim 1, wherein said first message includes a
first parameter that indicates whether said first node supports
data communication network addressing.
6. A system for routing calls through a communications network
comprising: means for initiating a call from a first subscriber in
a call-originating domain to a second subscriber in a data
communications domain; means for transmitting a first message from
a first node in said call-originating domain to a database in said
call-originating domain; means for locating a current data
communication network node parameter in said database, wherein said
network node parameter is associated with said second subscriber;
means for transmitting a second message that includes said located
data communication network node parameter from said database to
said first node; means for routing said call from said first node
to a data communications address indicated by said located data
communication network node parameter; and means for updating said
database when said second subscriber changes membership from a
first communication network provider to a data communication
network provider.
7. The system of claim 6, wherein said means for locating a network
node parameter further comprises: means for converting said located
data communication network node parameter to a data communications
address using a naming address database.
8. The system of claim 6, wherein the network node parameter is an
IP address.
9. The system of claim 7, wherein the data communications address
is an IP address.
10. The system of claim 6, wherein said first message includes a
first parameter that indicates whether said first node supports
data communication network addressing.
11. A method of routing calls through a communications network, the
communications network having a set of domains, at least one of the
domains in said set of domains being a data communications domain,
the method comprising the steps of: accessing, in a
call-originating domain included in the set of domains, a database
to obtain an address of a node of the data communications domain
which currently serves a called subscriber; and including the
address of the data communications domain which currently serves
said called subscriber as a parameter in a routing message for
routing a call from the call-originating domain to said node of
said data communications domain.
12. The method of claim 11, further comprising the step of:
providing a first message to said database indicating whether said
call-originating domain supports data communication network
addressing.
13. The method of claim 11, wherein the address included as a
parameter in the routing message is the IP address of the data
communications domain which currently serves said called
subscriber.
14. The method of claim 11, wherein the method further comprises
the step of: updating said database when said subscriber changes
membership from a communications domain in said set of domains to a
data communications domain whereby the address of the node of the
data communications domain is associated in said database with said
subscriber.
15. The method of claim 11, wherein said call-originating domain is
a telecommunications domain.
16. A system for routing calls through a communications network,
the communications network having a set of domains, at least one of
the domains in said set of domains being a data communications
domain, comprising: means for accessing, in a call-originating
domain included in the set of domains, a database to obtain an
address of a node of the data communications domain which currently
serves a called subscriber; and means for including the address of
the data communications domain which currently serves said called
subscriber as a parameter in a routing message for routing a call
from the call-originating domain to said node of said data
communications domain.
17. The system of claim 16, further comprising: means for providing
a first message to said database indicating whether said
call-originating domain supports data communication network
addressing.
18. The system of claim 16, wherein the address included as a
parameter in the routing message is the IP address of the data
communications domain which currently serves said called
subscriber.
19. The system of claim 16, wherein the system further comprises:
means for updating said database when said subscriber changes
membership from a communications domain in said set of domains to a
data communications domain whereby the address of the node of the
data communications domain is associated in said database with said
subscriber.
20. The system of claim 16, wherein said call-originating domain is
a telecommunications domain.
Description
BACKGROUND
[0001] Applicants' invention relates generally to number
portability in telecommunications systems and, more particularly,
to techniques for providing number portability towards Internet
service providers.
[0002] Number portability in telecommunication systems typically
permits end users (i.e., mobile subscribers) to retain the same
telephone numbers whenever the end users change from one
telecommunication service provider/operator domain to another
telecommunication service provider/operator domain. Without number
portability, service providers will be unable to accommodate the
relocation of a mobile subscriber from one service provider to
another without changing the subscriber's directory telephone
number.
[0003] Changing a directory telephone number in the event of
relocation of a subscriber occasions expense and effort for both
the subscriber and the telecommunications provider. For the
provider, it is an expensive process to administer the changes of
directory telephone numbers when a subscriber relocates from one
area to another. The administration required by the provider
includes both efforts to define available new numbers in the new
location and to update the existing directory. The relocated
subscriber also incurs expense in providing notice of the new
directory number to potential callers (friends and business
contacts). If such notice is not provided or retained by the
potential callers, calls may not be placed to the relocated
subscriber. Loss of calls to a relocated subscriber can result in
loss of social or business opportunity. Thus, number portability is
advantageous in that it permits relocated mobile subscribers, who
have changed service providers, to receive calls that otherwise
might be directed to the wrong service provider and therefore would
be lost.
[0004] For an understanding of number portability, a conventional
telecommunications network 10 is shown in FIG. 1 and is described
below. Network 10 includes a set of service provider domains
20A-20C and 20F. Three of the domains (particularly domains
20A-20C) are mobile telecommunications domains serving mobile
stations; domain 20F serves fixed stations. In the illustrated
network, domain 20F can be of a network type such as a public
switched network (PSTN) or integrated services digital network
(ISDN), for example. At least some of the areas served by domains
20 can be, and likely are, geographically coextensive. Some of the
domains 20 may also be served by differing service providers, e.g.,
different telecommunications operating companies.
[0005] Fixed station domain 20F includes at least one local
exchange 22F. Local exchange 22F is connected to a plurality of
fixed subscriber stations, only one of which (subscriber 24) is
shown in FIG. 1. Local exchange 22F is connected either directly or
ultimately (e.g., via transit exchanges) to a gateway exchange or
gateway node 26F. Gateway node 26F is connected to a database 30F.
Database 30F is, in turn, connected (e.g., for updating and
maintenance purpose) to a service management system 32F.
[0006] Mobile telecommunications domains 20A-20C each have
respective gateway nodes 26A-26C, each of which takes the form of
gateway mobile services switching center (GMSC) and accordingly are
respectively referred to as GMSCs 26A-26C.
[0007] Each gateway node GMSC 26 serves as an interface to external
domains 20 for one or more mobile services switching centers (MSCs)
40 which belong to the domain.
[0008] Although any given domain likely has a plurality of MSCs 20,
only a single MSC 40 is shown in domains 20 for purposes of
illustration. Each GMSC 26 is connected to the MSCs 40 in its
domain; MSCs 40 in the same domain may also be connected. Each MSC
40 in FIG. 1 is connected to serve at least one and preferably a
plurality of base station controllers (BSCs) 50. For example, MSC
40A serves base station controllers 50A-1 through 50A-m; MSC 40B(1)
serves base station controllers 50B(1)-1 through 50B(1)-m. It
should be understood that, typically, differing MSCs 40 serve a
differing number of base station controllers 50 The use of BSCs 50,
shown in the Figures, is for purposes of illustration. It will be
recognized that each MSC 40 can directly serve the BSs 60 without
any intermediary BSCs 50 in some mobile systems (e.g., TDMA
according to IS-136).
[0009] Each base station controller 50 is connected to one or more
base transceiver stations (BS) 60A-1 through 60A-1(q). The number
of base transceiver stations (BS) 60 per base station controller 50
can vary.
[0010] Each base transceiver stations (BS) 60 transmits and
receives radio frequency communications to and from a plurality of
mobile subscribers (MS) 70 in the geographical areas served by the
respective BS 60. For sake of simplicity and illustration, only one
mobile station 70 is shown in FIG. 1, although it should be
understood that each domain 20 serves hundreds if not thousands of
unillustrated mobile stations. The particular mobile station 70
depicted in FIG. 1 is shown as being served by base transceiver
station (BS) 60A-m(q).
[0011] Mobile telecommunications domains 20A-20C each include
respective databases 30A-30C. Databases 30A-30C are connected to
and maintained by service management systems 32A-32C, respectively.
Service management systems 32A-32C are connected to and supervised
by a master management system 32M.
[0012] Databases 30 are subscriber location servers which are
augmented with additional intelligence and are known as mobile
subscriber number portability databases. Databases 30 include
information which facilitates number portability for many types of
subscribers in their respective domains, including mobile
subscribers.
[0013] As will become more apparent below, the mobile
telecommunications domains 20A-20C described above comprise a
mobile subscriber number portability domain. In the number
portability domain, mobile subscribers can change service
providers, e.g., change from one of the domains to another, e.g.,
change from domain 20A to domain 20C, and still maintain their
"directory" number. FIG. 2 shows the circumstance where mobile
subscriber 71 has changed service providers. In particular, as
depicted in FIG. 2, mobile subscriber 71 has changed his
subscription from the provider which operates domain 20C to the
provider which operates domain 20B. In fact, at the time shown in
FIG. 2, mobile subscriber 71 is served by MSC 40B(1).
[0014] Upon the change of subscription as depicted in FIG. 2,
deletion of the subscriber (owning mobile station 71) from MSC 40C
was communicated to service management system (SMS) 32C, which
advised master service management system (SMS) 32M. SMS 32M
subsequently communicated the deletion of the subscriber to all
SMSs 32, including SMSs 32A, 32B, and 32F, which in turn updated
respective databases 30A, 30B, 32F, accordingly. Then, when the
subscriber joined the service provider which operates domain 20B,
SMS 32C advised master SMS 32M of the enlistment. SMS 32M
subsequently advised all SMSs 32 of the enlistment in domain 20B of
the subscriber, including SMSs 32A, 32C, 32F, which in turn updated
respective databases 30A, 30C, and 30F, accordingly. Therefore, in
accordance with the above process, the subscriber of mobile station
71 is able to retain the same directory number upon changing
service providers from domain 20C to domain 20B.
[0015] FIG. 2 further shows placement of a call from mobile
subscriber 70 in domain 20A to mobile subscriber 71 which has
changed from service provider 20C to service provider 20B. The
originating MSC 40A receives the mobile subscriber call via BS
60A-m(q) and BSC 50A-m. Then, in accordance with conventional
techniques, MSC 40A initiates a number portability request message
(Action 3-1; FIG. 2), such as, for example, the Number Portability
Request Invoke message utilized in ANSI41, to number portability
database 30A. However, in view of the previous updating of database
30A to reflect the mobile subscriber 71 changing service providers
(as discussed above), the parameter returned by database 30A at
action 3-2 includes the address of the new GMSC 26B, not the
address of the old GMSC 26C. Thus, at 3-2, number portability
database 30A initiates a number portability return message, such
as, for example, the Number Portability Request Return Result
(npreq) utilized in ANSI41, to the originating MSC 40A. This return
message includes a local portability routing number (LRN) to GMSC
26B. Thus, MSC 40A can then connect the originating call from
mobile subscriber 70 to GMSC 26B, and thereby to MSC40B(1), BSC
50B(1)-1, BS 60B(1)-1(a), and finally to called mobile subscriber
71. Therefore, mobile subscriber 70 is able to call mobile
subscriber 71, which has changed service providers from 20C to 20B,
using the same directory number.
[0016] Thus, as described above, a call-originating domain accesses
a mobile subscriber number portability database to obtain the
address of the gateway node of the telecommunications domain which
currently serves a called mobile subscriber. Use of the Number
Portability database will therefore advantageously permit a mobile
subscriber in a telecommunications system to retain the same
directory number whenever the subscriber changes from one service
provider/operator domain to another service provider/operator
domain.
[0017] Conventionally, however, the above described number
portability database is usable only for telecommunication service
providers and does not provide portability towards Internet service
providers. Applying conventional number portability techniques to
the portability of Internet addressing would be advantageous since
both current and proposed (Ipv6) Internet addressing systems are
provider-based and therefore, whenever a subscriber changes
providers, the subscriber's domain name changes as well as the
subscriber's IP address. Therefore it would be desirable to extend
application of the number portability database to permit a
subscriber to change from one Internet access provider to another
access provider without changing the subscriber's Internet IP
address and/or domain name. Additionally, number portability can be
applied to the internet service provider itself. Thus, if an
internet service provider's IP address changes, then number
portability can permit continued access by subscribers and/or other
data communication network. Extending application of the
conventional number portability database to Internet service
providers therefore advantageously permits a cohesive integration
between telecommunication and data communication networks. This
integration would permit telecommunication network operators and
data communications providers (e.g., internet service providers) to
improve service to their subscribers by providing access between
the two in a transparent fashion (i.e., telecom to datacom or
datacom to telecom). Extending application of the conventional
number portability database to internet service providers
additionally permits number portability between data communications
providers (i.e., datacom to datacom).
SUMMARY
[0018] These desirable characteristics and others are provided by
the following exemplary embodiments of the invention.
[0019] According to one exemplary embodiment of the invention a
method of routing calls through a communications network is
provided. The method of this exemplary embodiment comprises the
steps of: a) initiating a call from a first subscriber in a
call-originating domain to a second subscriber in a data
communications domain; b) transmitting a first message from a first
node in said call-originating domain to a database in said
call-originating domain; c) locating a current data communication
network node parameter in said database, wherein said network node
parameter is associated with said second subscriber; d)
transmitting a second message that includes said located data
communication network node parameter from said database to said
first node; e) routing said call from said first node to a data
communications address indicated by said located data communication
network node parameter; and f) updating said database when said
second subscriber changes membership from a first communication
network provider to a data communication network provider.
[0020] According to a second exemplary embodiment of the invention
a system for routing calls through a communications network is
provided. The system of this exemplary embodiment comprises: means
for initiating a call from a first subscriber in a call-originating
domain to a second subscriber in a data communications domain;
means for transmitting a first message from a first node in said
call-originating domain to a database in said call-originating
domain; means for locating a current data communication network
node parameter in said database, wherein said network node
parameter is associated with said second subscriber; means for
transmitting a second message that includes said located data
communication network node parameter from said database to said
first node; means for routing said call from said first node to a
data communications address indicated by said located data
communication network node parameter; and means for updating said
database when said second subscriber changes membership from a
first communication network provider to a data communication
network provider.
[0021] According to a third exemplary embodiment of the invention a
method of routing calls through a communications network, the
communications network having a set of domains, at least one of the
domains in said set of domains being a data communications domain,
is provided. The method of this exemplary embodiment comprises the
steps of: accessing, in a call-originating domain included in the
set of domains, a database to obtain an address of a node of the
data communications domain which currently serves a called
subscriber; and including the address of the data communications
domain which currently serves said called subscriber as a parameter
in a routing message for routing a call from the call-originating
domain to said node of said data communications domain.
[0022] According to a fourth exemplary embodiment of the invention
a system for routing calls through a communications network, the
communications network having a set of domains, at least one of the
domains in said set of domains being a data communications domain,
is provided. The system of this exemplary embodiment comprises:
means for accessing, in a call-originating domain included in the
set of domains, a database to obtain an address of a node of the
data communications domain which currently serves a called
subscriber; and means for including the address of the data
communications domain which currently serves said called subscriber
as a parameter in a routing message for routing a call from the
call-originating domain to said node of said data communications
domain.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The objects and advantages of the invention will be
understood by reading the following detailed description in
conjunction with the drawings in which:
[0024] FIG. 1 is a diagram of a conventional telecommunications
network that implements number portability;
[0025] FIG. 2 is a diagram of a call from a first mobile subscriber
to a second mobile subscriber that has changed service providers in
a telecommunications network;
[0026] FIG. 3 is a diagram of message parameters of exemplary
embodiments of the invention that are included in the Number
Portability Request Invoke message;
[0027] FIG. 4 is a diagram of message parameters of exemplary
embodiments of the invention that are included in the Number
Portability Request Return Result message;
[0028] FIG. 5 is a flow diagram of exemplary embodiments of the
invention; and
[0029] FIG. 6 is a diagram illustrating the messaging between
system components in accordance with exemplary embodiments of the
invention.
DETAILED DESCRIPTION
[0030] To provide portability of addresses across telecommunication
and data communication networks, exemplary embodiments of the
invention extend the conventional number portability principles,
described in the Background section above, to include Internet
addresses as well as the E.164 type of addresses currently returned
as the local number portability routing digits. To account for
Internet addressing, exemplary embodiments of the invention modify
the conventional number portability request invoke messages (e.g.,
ANSI41 NPREQ) and the number portability request return result
messages (e.g., ANSI41 npreq) to include additional information.
For request invoke messages, this additional information will
include a new parameter, "Transaction Capability," that indicates
whether Internet addressing is supported. For return result
messages, the additional information will include a new optional
routing address parameter, "Routing IP Address," that will permit
routing of the call on the IP network towards the ported Internet
service provider (e.g., voice over IP), and a new "Ported Gateway
Capabilities" parameter that specifies the protocol capabilities of
the ported gateway.
[0031] FIG. 3 illustrates modification of the conventional Number
Portability Request Invoke message 100 in accordance with exemplary
embodiments of the invention. As discussed above, "Transaction
Capability" flag 101 is added to the message 100 to indicate
whether the originating mobile switching center/end user
terminal/network node is capable of initiating Internet calls to a
destination IP address. If the flag 101 is "set," then the
capability of supporting Internet addressing is indicated.
Conversely, if the flag is "cleared," then Internet addressing is
not supported.
[0032] FIG. 4 illustrates modification of the conventional Number
Portability Request Return Result message in accordance with
further exemplary embodiments of the invention. In these further
exemplary embodiments, a "Routing IP Address" parameter 103 is
added to the Return Result message 102. This "Routing IP Address"
parameter is composed of sub-elements including Parameter ID 104,
Parameter Length 105, Address Type 106, and IP Address 107. The
Parameter ID 104 is an identifier or tag that specifies the type of
information included in the message, the Parameter Length 105
specifies the length of the "Routing IP Address" parameter, the
Address Type 106 specifies the type of IP address (e.g., Ipv4,
Ipv6, ATM, etc.) contained in the "Routing IP Address" parameter,
and the IP Address 107 specifies the IP address to which the called
subscriber is ported.
[0033] In addition to the "Routing IP Address," the protocol
capabilities of the ported gateway will be included in a new
"Ported Gateway Capabilities" parameter 130. This parameter will
specify the protocol capabilities of the ported gateway including
options such as SIP, H.323, L2TP tunneling (IETF), PPP (point to
point protocol, IETF), or ATM UNI.
[0034] It is noted that, though FIGS. 3 and 4 illustrate the
additional parameters of exemplary embodiments as being appended to
the end of the conventional Request Invoke and Return Result
messages, one skilled in the art will recognize that these
additional parameters could be located at any appropriate location
within the messages.
[0035] In further exemplary embodiments of the invention, the
conventional Number Portability database (30 in FIG. 2) can also be
modified to support a new entry for IP addresses. Additionally, a
"Name Address" entry could also be added to the NPDB. This "Name
Address" entry could be used for performing conversion to an IP
address before the NPDB answers a number portability request
message. This conversion could be performed, for example, by
querying a directory name server. For example, if the ported
address is a text address (e-mail, URL, etc.), the NPDB would query
a directory name server to request the IP address corresponding to
the text address. This IP address can then be returned via the
Return Result message (102 and 103 of FIG. 4).
[0036] A flow diagram of the operation of the exemplary embodiments
discussed above is shown in FIG. 5. When a communication is
initiated 110, the switching center/end user terminal/network node
(117, FIG. 6) will initiate 111 a Number Portability Request
message (118, FIG. 6) to the NPDB (30, FIG. 6) which will include
the "Transaction Capability" parameter. The NPDB then determines
112 whether the "Transaction Capability" parameter indicates that
the MSC/end user terminal/network node is capable of initiating
Internet calls to a destination IP address. If internet addressing
is not supported, meaning that the originating domain is not able
to set-up an internet call to the ported internet service provider,
the NPDB will return 113 an LRN in E.164 format that is the address
of the closest gateway to the ported internet service provider
(ISP) capable of performing protocol conversion. If, however,
Internet addressing is supported, the NPDB further analyzes the
ported address to determine whether the ported address is a text
address 114. If the ported address is a text address, then the NPDB
queries a directory name server to request the IP address which
corresponds to the text address.
[0037] The NPDB then returns 115 the IP address to which the called
subscriber is ported to the originating MSC/end user
terminal/network node via the "Routing IP Address" parameter (119,
FIG. 6). The NPDB additionally returns 120 the available protocol
options of the ported gateway via the "Ported Gateway Capabilities"
parameter. The originating domain (i.e., the mobile switching
center, end user terminal, or network node), then selects 122 one
of the options specified in the parameter for initiating 123 the
call towards the ported domain (or the new service provider).
[0038] Thus, as described above, exemplary embodiments of the
invention extend the number portability principle, implemented in
existing telecommunication networks, to support IP address
portability between telecommunication service providers and data
communication service providers or between data communication
service providers and other data communication service providers.
One skilled in the art will additionally recognize that a number of
standard protocols could be used to support the enhancements of the
exemplary embodiments of the invention described above with only
minor modifications. For telecommunications domains, these
protocols could include, e.g., ANSI41, GSM MAP, and ISUP (ISDN user
part). For data communications domains these protocols could
include, e.g., SIP and H.323.
[0039] Although a number of embodiments are described herein for
purposes of illustration, these embodiments are not meant to be
limiting. Those skilled in the art will recognize modifications
that can be made in the illustrated embodiments. Such modifications
are meant to be covered by the spirit and scope of the appended
claims.
* * * * *