Title of Invention

METHOD AND APPARATUS FOR CROSS PAGING IN A MULTI-NETWORK COMMUNICATION SYSTEM

Abstract Various embodiments are described which can serve to increase the cross pagin; call success rate in joint networks. Resource reservation by a requesting network (312) in the context of cross paging is described. In general, such resource reservation may be triggered by the occurrence of any one of a variety of events in conjunction with the requesting network determining tha. a communication session with an AT (301) is desirable. Examples of triggering events include the following: the AT subscribing for resource reservation as a matter of configuration, the AT having a particular call state and perhaps with regard to particular services, the AT requesting resource reservation (before or after being paged / notified of the requesting network's desire to provide service, the communication session for which the requesting network is requesting the AT is of a particular type, and/or resource reservation is an operational default system operation.
Full Text WO 2007/027547 PCT/US2006/033382
METHOD AND APPARATUS FOR CROSS PAGING IN A MULTI-NETWORK
COMMUNICATION SYSTEM
Reference(s) to Related Application(s)
The present application claims priority from provisional application,
Serial No. 60/713113, entitled "METHOD AND APPARATUS FOR CROSS
PAGING IN A MULTI-NETWORK COMMUNICATION SYSTEM," filed August
31, 2005, which is commonly owned and incorporated herein by reference in
its entirety.
This application is related to a co-pending provisional application,
Serial No. 60/678063, entitled "CROSS-PAGING BETWEEN
COMMUNICATION NETWORKS," filed May. 05, 2005, which is incorporated
herein by reference in its entirety.
This application is related to a co-pending provisional application,
Serial No. 60/681941, entitled "METHOD AND APPARATUS FOR AN
EXCHANGE OF PACKET DATA BETWEEN A WIRELESS ACCESS
TERMINAL AND A PACKET SWITCHED COMMUNICATION SYSTEM VIA A
CIRCUIT SWITCHED COMMUNICATION SYSTEM," filed May. 16, 2005,
which is incorporated herein by reference in its entirety.
Field of the Invention
The present invention relates generally to communications and, in
particular, to cross paging in multi-network communication systems.

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Background of the Invention
Third Generation Partnership Project 2 (3GPP2) Code Division Multiple
Access (CDMA), known as 3GPP2 cdma2000, networks support concurrent
services functionality for packet data and circuit switched voice
communication. The original system supports packet data and circuit
switched voice communication and is commonly referred to as the cdma2000
1X system or the 3G1X system. The cdma2000 1X system air interface is
standardized in 3GPP2 document C.S0001 through C.S0005 and
corresponding Telecommunication Industry Associates (TIA) standard TIA-
2000. In addition, new packet data standards, such as cdma2000 High Rate
Packet Data (cdma2000 HRPD) have been created. The cdma2000 HRPD
air interface is standardized in 3GPP2 documents C.S0024-A and C.S0063.
To provide communication continuity for a wireless unit moving
between overlaid 1x and packet data networks, it is desirable to provide
cross-paging capabilities that enable the wireless unit to be notified of
incoming-1x circuit voice calls when the unit is operating"on the HRPD-
network and that notify the unit of incoming packet data in the HRPD packet
data network when the unit is operating on the 1X network. U.S. patent
application publication no. 2004/0120283 can be referenced for a description
of certain aspects of cross-paging functionality. A 3GPP2 architecture which
supports cross paging typically includes a Mobile Switching Center (MSC), a
1x BS (Base Station), an HRPD AN (Access Network or Access Node), an
HRPD PCF (Packet Control Function), and a Packet Data Serving Node
(PDSN) and is standardized for two different RAN architectures in 3GPP2,
A.S0008-A and A.S0009.
Hybrid Access Terminals (HATs) are capable of supporting both the
3G1x and HRPD air interface technologies. In a joint circuit switched, packet
switched communication network, such as the 3GPP2 3G1x-HRPD network
(in which the 3G1x network provides circuit switched voice support and the
HRPD network provides packet switched service), cross paging is used to

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page a HAT on the network where it is currently monitoring a forward link
channel. Thus, cross paging is used to inform the HAT of a call on another
network where the HAT is registered for service but not currently monitoring a
forward link channel.
When a HAT is paged for service on a second network via a first
network, it releases any active call on the first network and begins monitoring
a forward link on the second network, from which it is being paged, to
complete the call. For example, a HAT may be paged for circuit voice service
from the 3G1x network while the HAT is in the HRPD network, currently
engaged in an active packet data call. Alternatively, the HAT may be paged
for packet data service from the HRPD network while in the 3G1x network
monitoring a forward link channel.
When a HAT is cross paged for service in another network, a condition
known as 'ghost ring' may occur. A 'ghost ring' occurs when the HAT
responds to a page from a second network while in the first network,
terminates any active call in the first network, and attempts to initiate the new
call for which it was paged but fails because network resources required to
support the call (e.g., air traffic channels or network bearer connections) are
not available in the second network (even though they may have been
available when the HAT was originally paged, as may occur in networks
operating at or near full capacity). When such a scenario occurs, not only
does the HAT fail to successfully initiate the call in the second network, but it
also may have dropped an existing call in the first network to receive the new
call. Generally, then, this is a problem in cross paging architectures where
each RAN independently manages its network resources.
FIG. 1 is a signaling flow diagram 10 depicting, in accordance with the
prior art (see the 3GPP2-A.S0008-A standard, May 2005 V&V version), a
HAT being paged for HRPD packet data service via a 1x network air interface
while the HAT is engaged in a circuit voice call. The HAT is registered in the
1x system and on a traffic channel when packet data for the HAT arrives at
the HRPD AN/PCF supporting the HAT's packet data session in the packet

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data network. The arrival of data at the HRPD access network triggers an
HRPD cross page in the 1x network.
In prior art signaling 11, it is assumed that, when the HAT arrives on
the HRPD network after releasing its circuit call, a connection will successfully
be established between the HAT and the HRPD network. However, if for any
reason the connection fails to be established due to a lack of network
resources, not only will the new call fail to be delivered in the HRPD network,
but the 1x circuit call will also have been unnecessarily dropped.
Operators are beginning to deploy Voice over Internet Protocol (VoIP)
and Video Telephony (VT) on their HRPD packet data networks and will rely
on cross paging to page HATs for packet data service in the 3G1X circuit
network. Therefore, a need exists to increase the cross-paging call success
rate in joint networks such as the 3GPP2 3G1X-HRPD communication
networks.
Brief Description of the Drawings
FIG. 1 is a signaling flow diagram depicting, in accordance with the
prior art, a HAT being paged for HRPD packet data service via a 1x network
air interface while the HAT is engaged in a circuit voice call.
FIG. 2 is a block diagram depiction of a wireless communication
system in accordance with multiple embodiments of the present invention.
FIG. 3 is a more generalized block diagram depiction of a wireless
communication system in accordance with multiple embodiments of the
present invention.
FIG. 4 is a signaling flow diagram depicting a HAT being cross paged
for HRPD packet data service via a 1x network air interface in accordance
with multiple embodiments of the present invention.

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FIG. 5 is a signaling flow diagram depicting a HAT being cross paged
for HRPD packet data service via a 1x network air interface in accordance
with multiple embodiments of the present invention.
FIG. 6 is a signaling flow diagram depicting a HAT being cross paged
for 1x service via an HRPD air interface in accordance with multiple
embodiments of the present invention.
FIG. 7 is a block diagram depicting an illustrative message definition
for an event notification message in accordance with multiple embodiments of
the present invention.
FIG. 8 is a block diagram depicting an illustrative message definition
for a service request message in accordance with multiple embodiments of
the present invention.
FIG. 9 is a block-diagram depicting an illustrative message definition
for a service response message in accordance with multiple embodiments of
the present invention.
FIG. 10 is a signaling flow diagram depicting a HAT being cross paged
for 1x service via an HRPD air interface in accordance with multiple
embodiments of the present invention.
FIG. 11 is a block diagram depicting an illustrative message definition
for a paging request message in accordance with multiple embodiments of
the present invention.
FIG. 12 is a block diagram depicting an illustrative message definition
for a paging response message in accordance with multiple embodiments of
the present invention.

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Specific embodiments of the present invention are disclosed below
with reference to FIGs. 2-12. Both the description and the illustrations have
been drafted with the intent to enhance understanding. For example, the
dimensions of some of the figure elements may be exaggerated relative to
other elements, and well-known elements that are beneficial or even
necessary to a commercially successful implementation may not be depicted
so that a less obstructed and a more clear presentation of embodiments may
be achieved. In addition, although the signaling flow diagrams above are
described and shown with reference to specific signaling in a specific order,
some of this signaling may be omitted or some may be combined, sub-
divided, or reordered without departing from the scope of the claims. Thus,
unless specifically indicated, the order and grouping of signaling is not a
limitation of other embodiments that may lie within the scope of the claims
Simplicity and clarity in both illustration and description are sought to
effectively enable a person of skill in the art to make, use, and best practice
the present invention in view of what is already known in the art. One of skill
in the art will appreciate that various modifications andchanges may be made
to the specific embodiments described below without departing from the spirit
and scope of the present invention. Thus, the specification and drawings are
to be regarded as illustrative and exemplary rather than restrictive or all-
encompassing, and all such modifications to the specific embodiments
described below are intended to be included within the scope of the present
invention.
Detailed Description of Embodiments
Various embodiments are described which can serve to increase the
cross paging call success rate in joint networks such as the 3GPP2 3G1X-
HRPD communication networks. Resource reservation by a requesting
network in the context of cross paging is described. In general, such resource

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reservation may be triggered by the occurrence of any one of a variety of
events in conjunction with the requesting network determining that a
communication session with an AT is desirable. Examples of triggering events
include the following: the AT subscribing for resource reservation as a matter
of configuration, the AT having a particular call state and perhaps with regard
to particular services, the AT requesting resource reservation (before or after
being paged / notified of the requesting network's desire to provide service,
the communication session for which the requesting network is requesting the
AT is of a particular type, and/or resource reservation is an operational default
system operation.
The disclosed embodiments can be more fully understood with
reference to FIGs. 2-12. FIG. 2 is a block diagram depiction of a wireless
communication system 100 in accordance with multiple embodiments of the
present invention. At present, standards bodies such as OMA (Open Mobile
Alliance), 3GPP (3rd Generation Partnership Project), 3GPP2 (3rd
Generation Partnership Project 2) and IEEE (Institute of Electrical and
Electronics Engineers) 802 are developing standards specifications for
wireless telecommunications systems. (These groups may be contacted via
http://www.openmobilealliance.com, http://www.3qpp.org/,
http://www.3qpp2.com/ and http://www.ieee802.org/, respectively.)
Communication system 100 represents a system having an architecture in
accordance with multiple 3GPP2 technologies cdma2000 1X (also known as
3G1X) and HRPD (also known as 1xEV-DO or IS-856)), suitably modified to
implement the present invention. For example, nodes 121 and 122 have
architectures in accordance with 1X and HRPD, respectively, which are
suitably modified to implement the present invention.
Alternative embodiments of the present invention may be implemented
in communication systems that employ other or additional technologies such
as, but not limited to, others described in the 3GPP2 specifications, those
described in the 3GPP specifications (e.g., GSM, GPRS, EDGE, W-CDMA,
UTRAN, FOMA, UMTS, HSDPA, and HSUPA), those described in the IEEE's
802.xx specifications, those described in the OMA standards specifications,

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those described in the IS-136 (TDMA Third Generation Wireless Standards)
specification, those described in the lS-95 (CDMA) specification, 1xEV-DV
technologies, and integrated dispatch enhanced network technologies.
More specifically, communication system 100 comprises HAT 101,
nodes 121 and 122, Access Network Authentication, Authorization and
Accounting (AN-AAA) entity 142, Mobile Switching Center (MSC) 151, Packet
Data Serving Node (PDSN) 161, TIA-41 network 171, public switched
telephone network (PSTN) 173, and IP-network 175. Those skilled in the art
will recognize that FIG. 2 does not depict all of the network equipment
necessary for system 100 to operate but only those system components and
logical entities particularly relevant to the description of embodiments herein.
For example, 1X circuit node 121 is known to comprise devices such as base
transceiver stations (BTSs) and base site controllers (BSCs), and packet data
node 122 is known to comprise devices such as access networks (ANs) and
packet control functions (PCFs).
FIG. 3 is a block diagram depiction of a wireless communication
system 300 in accordance with multiple embodiments of the present
invention. Communication system 300 is depicted in a more generalized
manner than communication system 100. In particular, access terminal (AT)
301 and two networks are shown, serving network 311 and target network
312. Those skilled in the art will recognize that FIG. 3 does not depict all of
the physical fixed network components necessary for system 300 to operate
but only those system components and logical entities particularly relevant to
the description of embodiments herein.
For example, FIG. 3 depicts networks 311-312 as respectively
comprising transceivers 325-326, network interfaces 321-322, and processing
units 323-324. In general, components such as processing units, network
interfaces and transceivers are well-known. For example, network processing
units are known to comprise basic components such as, but neither limited to
nor necessarily requiring, microprocessors, microcontrollers, memory devices,
application-specific integrated circuits (ASICs), and/or logic circuitry. Such
components are typically adapted to implement algorithms and/or protocols

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that have been expressed using high-level design languages or descriptions,
expressed using computer instructions, expressed using signaling flow
diagrams, and/or expressed using logic flow diagrams.
Thus, given an algorithm, a logic flow, a messaging / signaling flow,
and/or a protocol specification, those skilled in the art are aware of the many
design and development techniques available to implement a network
processing unit that performs the given logic. Therefore, networks 311-312
represent known networks that have been adapted, in accordance with the
description herein, to implement multiple embodiments of the present
invention. Furthermore, those skilled in the art will recognize that aspects of
the present invention may be implemented in and across various physical
components and none are necessarily limited to single platform
implementations. For example, the network aspects of the present invention
may be implemented in / across one or more of the following components: a
BTS, a BSC, an AN, and / or an MSC.
Thus, in certain embodiments, such as those in which system 100
components are mapped onto the generalized system 300 depiction, the
network representing the 1X system (either network 311 or network 312,
depending on which is the serving network) may comprise MSC 151 (or a
portion thereof) and circuit node 121 (or a portion thereof). In such an
embodiment, then, networking interface 321 (or 322) and processing unit 323
(or 324) may be respectively distributed across corresponding aspects of
MSC 151 and circuit node 121. A more general example, then, would be
transceivers 325-326, network interfaces 321-322, and / or processing units
323-324 being distributed across corresponding aspects of one or more of the
following components: a BTS, a BSC, an AN, and / or an MSC.
Networks 311 and 312 respectively use air interfaces comprising
channel groups 111 and 112 for communication with AT 301. In 3GPP2
embodiments, channel groups 111 and 112 each comprise traffic channels,
which are dynamically assigned and de-assigned to support user services,
and a variety of well-known non-traffic channel types, such as broadcast
channels, paging channels, access channels and common control channels,

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all in accordance with the particular 3GPP2 signaling technology used. For
example, channel groups 111 and 112 may respectively comprise a 1X
channel group and an HRPD channel group, or vice versa.
Access terminals (ATs), or remote units, may serve as mobile stations
(MSs); however, ATs are not necessarily mobile nor able to move. Also,
remote units / ATs may be wireless devices but they do not necessarily need
to be wireless; a remote unit / AT may be either wired or wireless. Moreover,
remote unit / AT platforms are known to refer to a wide variety of consumer
electronic platforms such as, but not limited to, mobile stations (MSs), user
equipment (UE), terminal equipment, gaming devices, personal computers,
personal digital assistants (PDAs), cable set-top boxes and satellite set-top
boxes. In particular, AT 301 comprises processing unit 302, transceiver 303,
a keypad (not shown), a speaker (not shown), a microphone (not shown), and
a display (not shown). Processing units, transceivers, keypads, speakers,
microphones, and displays as used in ATs are all well-known in the art.
For example, AT processing units are known to comprise basic
components such as, but neither limited to nor necessarily requiring,
microprocessors, digital-signal processors (DSPs), microcontrollers, memory
devices, application-specific integrated circuits (ASICs), and/or logic circuitry.
Such AT components are typically adapted to implement algorithms and/or
protocols that have been expressed using high-level design languages or
descriptions, expressed using computer instructions, expressed using
messaging / signaling flow diagrams, and/or expressed using logic flow
diagrams. Thus, given an algorithm, a logic flow, a messaging / signaling flow,
a call flow, and/or a protocol specification, those skilled in the art are aware of
the many design and development techniques available to implement user
equipment that performs the given logic. Therefore, AT 301 represents a
known AT that has been adapted, in accordance with the description herein,
to implement embodiments of the present invention.
Operation of various embodiments in accordance with the present
invention occur substantially as follows. Relevant operation of some of the
embodiments illustrated by FIG. 3 begins with AT 301 being registered with

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both networks 311 and 312 but being served by serving network 311. Thus,
AT processing unit 302 is obtaining communication service from serving
network 311 via AT transceiver 303 and network processing unit 323 is
providing communication service to AT 301 via network transceiver 325. This
communication service being provided to AT 301 by serving network 311 may
take various forms depending on AT 301's service state. For example, AT
301 may be involved in a service via a traffic channel of air interface 111
(e.g., a busy service state) or merely monitoring a paging or broadcast
channel of air interface 111 (e.g., an idle service state). Thus, communication
service of various forms is provided AT 301 by serving network 311 via air
interface 111. Having a desire to provide service to AT 301, target network
312 requests AT 301 for service via network interface 322 and serving
network 311. Target network 312 may determine that a communication
session (or service connection) with the AT is desirable in response to
receiving signaling for a service involving the AT such as a circuit-switched
service or a packet data service.
For example, in the case in which serving network 311 is a 1X network
and target network 312 an HRPD network, a packet data service such as a
packet data call request for AT 301 could be received by target network 312
(e.g., data arriving for delivery to AT 301). In another example in which
serving network 311 is an HRPD network and target network 312 a 1X
network, a circuit-switched service such as a circuit-switched call request for
AT 301 could be received by target network 312, thereby creating the need
for a communication session with AT 301.
Thus, serving network processing unit 323 receives a message from
target network 312 via network interface 321 requesting to provide
communication service to AT 301. Depending on the embodiment and/or the
particular scenario at hand, the message requesting to provide service may
take the form of a service request or a paging request message. Signaling
408 (FIG. 4) and signaling 504 (FIG. 5), both A1-BS Service Request
messages, are examples of service request messages, while signaling 603

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(FIG. 6) and signaling 1006 (FIG. 10) are examples of paging request
messages.
In some embodiments in response to receiving the message
requesting to provide communication service to AT 301, serving network 311
pages (i.e., generally notifies in some manner) AT 301. AT processing unit
302 receives the page (i.e., notification) via transceiver 303, and depending
on the embodiment may respond by indicating that resource reservation is
requested. AT processing unit 302, via transceiver 303, may send an
indication that resource reservation is requested, for the communication
service that is to be provided by target network 312, before AT 301 leaves the
communication service of serving network 311. In other words, AT 301 may
be trying to ensure that target network 312 will have the resources required to
provide the service for which AT 301 is being requested, before AT 301 drops
a communication service (such as an ongoing call) being provided by serving
network 311.
Depending on the embodiment, in response to receiving the message
from target network 312 requesting to provide communication service to AT
301, serving network 311 sends an indication to target network"312" that
resource reservation is requested. This indication may be sent in response to
receiving a resource reservation request from AT 301 (e.g., after paging /
notifying AT 301) or as a result of a determination by serving network 311 that
resource reservation is desirable (perhaps before paging / notifying AT 301).
For example, AT 301 may have previously subscribed to resource reservation
via serving network 311 or AT 301 may be actively involved in a
communication service via serving network 311 (such as a call). Thus,
processing unit 323 may determine to send an indication to target network
312 that resource reservation is requested either before or after paging /
notifying AT 301. Signaling 505 (FIG. 5), an A1-BS Service Response
message, and signaling 605 (FIG. 6), a Paging Response message (which
could alternatively be a Clear Request message), are examples of indications
that resource reservation is requested. FIG. 12 is a block diagram (1200)
depicting an illustrative message definition for a paging response message, a

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Paging Response message in particular, that includes an element ("RR
REQUEST") for indicating whether resource reservation is requested.
In response to receiving via network interface 322 an indication that
resource reservation is requested, target network processing unit 324
reserves at least one communication resource in anticipation of providing
service to AT 301. Depending on the embodiment and the particular
communication service that target network 312 seeks to provide to AT 301,
communication resources such as an air interface traffic channel and/or a
network bearer resource, such as an A8 connection, an A10 connection,
terrestrial circuits, or SCCP resources, may be reserved.
After reserving resources (and depending on the embodiment this may
occur in response to various events), target network processing unit 324, via
network interface 322, may indicate to serving network 311 that resource
reservation has occurred in anticipation of providing service to AT 301.
Signaling 408 (FIG. 4) and signaling 509 (FIG. 5), both A1-BS Service
Request messages, and signaling 1006 (FIG. 10) and signaling 608 (FIG. 6),
both Paging Request messages, are examples of indications that resource
reservation has occurred. In addition, FIG. "8 is "a block" "diagram (800)
depicting an illustrative message definition for a service request message, a
BS Service Request message in particular, that includes an element ("RR
INDICATION") for indicating whether anticipatory resource reservation has
occurred. Similarly, FIG. 11 is a block diagram (1100) depicting an illustrative
message definition for a paging request message, a Paging Request
message in particular, that includes an element ("RR INDICATION") for
indicating whether anticipatory resource reservation has occurred.
Serving network processing unit 323, via network interface 321,
receives the indication that resource reservation has occurred in anticipation
of providing service to AT 301. Depending on the embodiment, processing
unit 323 may proceed with paging / notifying AT 301, via transceiver 325, for
the communication service to be provided by target network 312, in response
to receiving the indication that resources have been reserved. However,

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paging / notifying AT 301 need not be in response to an indication of resource
reservation, although from an AT user's perspective this may be desirable.
In general, resource reservation by a target network may be triggered
by the occurrence of any one of a variety of events in conjunction with the
target network determining that a communication session with an AT is
desirable. Examples of triggering events include the following: the AT
subscribing for resource reservation as a matter of configuration, the AT
having a particular call state (such as busy, e.g.) and perhaps with regard to
particular services (such as a voice or data call, e.g.), the AT requesting
resource reservation (before or after being paged / notified of the target
network's request to provide service, the communication session for which the
target network is requesting the AT is of a particular type (e.g., a packet data
service type, examples of which might include a voice over internet protocol
(VoIP) call and / or a video telephony (VT) call), and/or resource reservation is
default system operation. Various specific embodiments which involve
conveying information about these triggering events and/or further defining
these triggering events for particular networks and technologies have been
provided above and will be added to in the discussion that follows.
The timing of and manner in which information about particular
triggering events is communicated (or indicated) in a system is highly specific
to each embodiment, and many possibilities exist. For example, some
embodiments employ the use of a message such as an event notification
message. FIG. 7 is a block diagram depicting an illustrative message
definition for an event notification message in accordance with multiple
embodiments of the present invention. Messaging blocks 710 and 720 depict
the "EVENT" element and some detail of its makeup. Messaging block 730
provides an illustrative list of "EVENT IDENTIFIERS" that may be used;
however, this list is merely an example. A subset of the list may be used,
additional event indicators may be added, an altogether different list of event
indicators may be used, or event indicators may be incorporated into
messaging other than the dedicated messaging that the event notification
message represents. For example, certain event indicators may be added to

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certain other signaling to indicate event information as that signaling is used.
Signaling 401 (FIG. 4) and signaling 1002 (FIG. 10) are examples of event
notification messaging being used.
Some examples of event indicators, whether incorporated into an
event notification message or not, include the following: cross-paging-related
configuration information for the AT, call state information for the AT, location
information for the AT, and resource reservation subscription information for
the AT. The cross-paging-related configuration information for the AT may
include the resource reservation subscription information or somehow, and
perhaps additionally, indicate how resource reservation is to be handled for
the AT. The cross-paging-reiated configuration information may be sent by
the AT to the serving network upon arrival of the AT in the serving network,
and if not sent sooner, may be sent to the target network in response to the
target network's request of the serving network to page the AT.
The call state information for the AT may include information indicating
call states such as a busy call state, an idle call state, an active packet data
session state, and / or a dormant packet data session state. Other call states
could be added, of course, and information indicating the present call state of
the AT in the serving network may be sent to the target network in response
to the present call state of the AT changing. In other words, the serving
network may keep the target network apprised of call state changes for the
AT in order to enable the target network to make resource reservation
decisions.
Information indicating the location of the AT in the serving network may
also be sent to the target network. For example, an indication of which cell is
serving the AT may be sent. The target network may then use the AT location
information in order to more efficiently reserve resources. For example, fewer
air interface and / or network bearer resources may need to be reserved by
the target network if sufficient location information can be provided for the AT.
In addition to or instead of an event notification message, location
information for the AT may be sent in a service response message. FIG. 9 is
a block diagram (900) depicting an illustrative message definition for a service

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response message in accordance with multiple embodiments of the present
invention. Block diagram 900 depicts the "LOCATION INFORMATION"
element of an illustrative BS Service Response message along with some of
its other elements. Signaling 505 (FIG. 5) is an example of such a BS Service
Response message being used.
FIGs. 4, 5, 6 and 10 are detailed signaling flow diagrams that will be
used in the following description of some specific embodiments. These
embodiments are provided in such detail in order to illustrate and describe
some specific implementations of various aspects of the present invention,
the scope of the present invention being defined by the appended claims.
FIGs. 4 and 5 are signaling flow diagrams (400 and 500) that depict a HAT
being cross paged for HRPD packet data service via a 1x network air
interface in accordance with multiple embodiments of the present invention.
The descriptions of diagrams 400 and 500 refer to the following list of HRPD
cross paging triggers:
1. MSC provides indication that HAT is subscribed for guaranteed
resource reservation (HLR configuration). The indicationcould be sent
(a) once when the HAT arrives in the 1x network or (b) when the HAT
is paged for HRPD packet data service
2. HRPD RAN sends HRPD cross-page request to 3G1x circuit network.
MSC responds with an indication that HAT is currently busy with a 1x
circuit call. HRPD network initiates resource reservation and reinitiates
cross-paging in the 1x network with a guaranteed resource indication
to MSC.
3. Tunneled HRPD air interface signaling message requesting resource
reservation from the HAT is received at HRPD AN/PCF (a) prior to or
(b) after being paged.
4. In response to an indication from PDSN of incoming VoIP or VT call.
PDSN determines this when the packet data for the HAT arrives from a
SIP server and signals information to HRPD RAN.

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5. 1x RAN sends an indication to HRPD AN when HAT is engaged in a 1x
circuit call.
6. HRPD RAN always guarantees network resources prior to cross-
paging HAT for HRPD packet data service in circuit network.
The following is a detailed description of the signaling flow of diagram 400 by
reference number:
401) HAT is currently in the 1x network. MSC sends an Event
Notification message to the HRPD network (AN or PCF)
containing at least one of the following pieces of information
(may not be sent for triggers 4,6)
1. HAT is subscribed for guaranteed resource
reservation (1a)
2. HAT is busy with a 1x circuit voice call (5)
3. HAT has requested resource reservation (3a)
The MSG may include the HATs current location information in
the message, if available, to facilitate resource reservation.
402) Packet data arrives for the HAT at the packet data session
anchored at the HRPD network while the MS is engaged in a
circuit voice call on the 1x network. A field in GRE header may
indicate packet data that may required resource reservation
(Trigger 4, e.g. VT, VoIP)
403) HRPD PCF sends A9-BS Service Request message to the
HRPD AN.
404) HRPD AN responds with an A9-BS Service Response message
to HRPD PCF.

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In response to one of the triggers described above, the
HRPD network performs steps e, f, g before requesting a
cross page from the 1x network.
405) HRPD AN sends an A9-Setup-A8 message to HRPD PCF
request an A8 bearer connection.
406) HRPD PCF responds with A9-Connect-A8 after allocating an A8
bearer connection.
407) The HRPD AN reserves a traffic channel for the HAT's packet
data call and exchanges A11-Registration Request/A11-
Registration Response containing Active Start AL record to the
PDSN
408) HRPD AN sends an A1-BS Service Request message to the
MSC to request the MSC to page the HAT for packet data
service. The message may include an indication that resources
have been reserved for the HAT in the HRPD network (to
prevent 'ghost ring'). The AN starts timer TRsrc-Rsv
409)" The 1X MSC responds with an A1-BS Service Response to
HRPD RAN. The HRPD RAN stops timer T311.
410) MSC sends an A1 -ADDS Deliver message to the 1 xBS to page
the HAT for HRPD packet data service.
411) 1xBS sends a data burst message containing a Page message
for HRPD packet data service containing and the HRPD service
option to the HAT.
412) HAT responds with a Layer 2 Ack
413) 1 xBS sends an ADDS Deliver Ack message to MSC.
414) The HAT ends its 1x circuit call and releases the connection
with the 1x RAN.
415) The HAT re-establishes an HRPD connection with the HRPD
RAN. The AN cancels timer TRsrc-Rsv.
416) Packet data begins to flow between the AT and HRPD network.

WO 2007/027547 PCT/US2006/033382
19
The following is a detailed description of the signaling flow of diagram 500 by
reference number:
501) Packet data arrives for the HAT at the packet data session
anchored at the HRPD network while the MS is engaged in a
circuit voice call on the 1x network.
502) HRPD PCF sends A9-BS Service Request message to the
HRPD AN,
503) HRPD AN responds with an A9-BS Service Response message
to HRPD PCF.
504) HRPD AN sends an A1-BS Service Request message to the
MSC requesting it to page the HAT for packet data service.
505) In response to Trigger 1 b (HAT is subscribed for resource
reservation) or trigger 2 (HAT is engaged in a circuit voice call),
MSC responds to HRPD AN with A1-BS Service Response
requesting resource reservation for the call. MSC includes HAT
location information to aid HRPD network in determining where
resources shouldbe reserved. Alternatively; AT is queried for
the information.
506) HRPD AN sends an A9-Setup-A8 message to HRPD PCF
request an A8 bearer connection.
507) HRPD PCF responds with A9-Connect-A8 after allocating an A8
bearer connection.
508) The HRPD AN reserves a traffic channel for the HAT's packet
data call and exchanges A11-Registration Request/A11-
Registration Response containing Active Start AL record to the
PDSN
509) HRPD AN sends an A1-BS Service Request message to the
MSC to request the MSC to page the HAT for HRPD packet
data service. The message may include an indication that
resources have been reserved for the HAT in the HRPD network
(to prevent 'ghost ring'). The AN starts timer TRsrc-Rsv .

WO 2007/027547 PCT/US2006/033382
20
510) The 1X MSC responds with an A1-BS Service Response to
HRPD RAN. The HRPD RAN stops timer T311.
511) MSC sends an A1-ADDS Deliver message to the 1xBS
containing an HRPD Page Request sent by the HRPD AN.
512) 1xBS sends a data burst message containing a Page message
for HRPD packet data service containing and the HRPD service
option to the HAT.
513) HAT responds with a Layer 2 Ack
514) 1xBS sends an ADDS Deliver Ack message to MSC.
515) The HAT drops its 1x circuit call and releases connection with
the 1x RAN.
516) The HAT re-establishes an HRPD connection with the HRPD
RAN. The AN cancels timer TRsrc-Rsv .
517) Packet data begins to flow between the AT and HRPD network.
FIGs. 10 and 6 are signaling flow diagrams (1000 and 600) that depict
a HAT being cross paged for 1x service via an HRPD air interface in
accordance with multiple embodiments of the present invention. The
descriptions of diagrams 1000 and 600 refer to the following list of 3G1X
cross paging triggers:
1. HAT's subscriber profile indicates HAT is subscribed for
guaranteed resource reservation (HLR configuration). The
indication could be sent (a) once when the HAT arrives in the
HRPD network or (b) when the HAT is paged for 1X circuit voice
service
2. 3G1X circuit network sends 1x cross-page request to HRPD
network. HRPD network responds with indication that HAT is
engaged in an active packet data session call (data actively being
exchanged between HAT and packet data network, i.e a traffic
channel is assigned and there is an air interface connnection).

WO 2007/027547 PCT/US2006/033382
21
3. Circuit network reserves network resources and re-pages HAT on
HRPD network for circuit voice call in response to tunneled air
interface signaling from HAT requesting resource reservation (a)
prior to or (b) after being paged.
4. HRPD network informs 1x network in real-time whenever HAT's
session transitions from the dormant to the active state, (note this is
different than trigger '2'). 3G1X network reserves network resources
prior to cross-paging HAT for 1x circuit service whenever HAT is
engaged in a packet data session.
5. 3G1X RAN always guarantees resources before cross-paging HAT
for 1x circuit voice in HRPD packet data network.
The following is a detailed description of the signaling flow of diagram 1000
by reference number:
1001) The mobile is in an active packet data session on HRPD
system.
-1002) HRPD RAN sendsan Event Notification message to the 1X
MSC containing at least one of the following pieces of
information (may not be sent for trigger 5)
1. HAT is subscribed for guaranteed resource reservation (1a)
2. HAT is requesting resource reservation (3a)
3. HAT has transitioned to the packet data active state (4)
The HRPD RAN also includes the HATs current location information in
the message, if available, to facilitate resource reservation.
1003) The 1X MSC receives a voice call from the circuit core network
destined for the mobile.
1004) 1X MSC send a 3G1x Paging Request message to the 1X BSC
(may include the HAT's location information, if available, to

WO 2007/027547 PCT/US2006/033382
22
facilitate resource reservation). The Paging Request includes a
field indicating resource shall be reserved for the mobile. The 1x
BS reserves network resources including air interface traffic
channels for the HAT.
1005) After 1X RAN allocates network resources and radio traffic
channel for HAT, it then responds with a Paging Response
message to 1X MSC. The Paging Response message contains
an indication that resources have been reserved for the HAT.
1006) 1X MSC sends Paging Request to HRPD RAN indicating that
1X network resources have been reserved.
1007) HRPD RAN pages the HAT for the 1X call via CSNA.
1008) If user accept the 1X call, the HAT transitions to the dormant
packet data state and switches to 1X system for the HAT
terminated voice call.
The following is a detailed description of the signaling flow of diagram 1000
by reference number:
601) The mobile is in an active packet data call on HRPD system.
602) The 1X MSC receives a voice call from the circuit core network
destined for the mobile.
603) Since 1X MSC knows that the HAT is in the HRPD network, 1X
MSC send a 3G1x Paging Request message to HRPD RAN.
604) 1X MSC also sends a 3G1X Paging Request message to 3G1x
BS with VPI included.
605) HRPD RAN indicates that the 1X resource needs to be reserved
for the HAT before paging it in the HRPD network, the HRPD

WO 2007/027547 PCT/US2006/033382
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RAN responds with a Paging Response message to 1X MSC
indicating "Request Reserve 1X resource".
606) Upon receipt of the Paging Response from HRPD RAN, 1X
MSC sends a Paging Request message indicating that reserved
resources are required in the 1X RAN. When the 1X RAN
receive the Paging Request, it reserves network resources and
air interface traffic channel for the HAT.
607) 1X BS allocates network resources and radio traffic channel for
HAT, then responds with a Paging Response message to 1X
MSC. The Paging Response message contains a field indicating
that the resource has been reserved for the HAT.
608) 1X MSC sends Paging Request to HRPD RAN indicating that
1X network resources have been reserved.
609) HRPD RAN pages the HAT for the 1X call via CSNA.
610) If user accept the 1X call, the HAT transitions to the dormant
packet data state and switches to 1X system for the HAT
terminated voice call.
Benefits, other advantages, and solutions to problems have been
described above with regard to specific embodiments of the present
invention. However, the benefits, advantages, solutions to problems, and any
element(s) that may cause or result in such benefits, advantages, or
solutions, or cause such benefits, advantages, or solutions to become more
pronounced are not to be construed as a critical, required, or essential feature
or element of any or all the claims.
As used herein and in the appended claims, the term "comprises,"
"comprising," or any other variation thereof is intended to refer to a non-

WO 2007/027547 PCT/US2006/033382
24
exclusive inclusion, such that a process, method, article of manufacture, or
apparatus that comprises a list of elements does not include only those
elements in the list, but may include other elements not expressly listed or
inherent to such process, method, article of manufacture, or apparatus. The
terms a or an, as used herein, are defined as one or more than one. The
term plurality, as used herein, is defined as two or more than two. The term
another, as used herein, is defined as at least a second or more. The terms
including and/or having, as used herein, are defined as comprising (i.e., open
language). The term coupled, as used herein, is defined as connected,
although not necessarily directly, and not necessarily mechanically.
Terminology derived from the word "indicating" (e.g., "indicates" and
"indication") are intended to encompass all the various techniques available
for communicating or referencing the object being indicated. Some, but not all
examples of techniques available for communicating or referencing the object
being indicated include the conveyance of the object being indicated, the
conveyance of an identifier of the object being indicated, the conveyance of
information used to generate the object being indicated, the conveyance of
some part or portion of the object being indicated; the conveyance" of some
derivation of the object being indicated, and the conveyance of some symbol
representing the object being indicated. The terms program, computer
program, and computer instructions, as used herein, are defined as a
sequence of instructions designed for execution on a computer system. This
sequence of instructions may include, but is not limited to, a subroutine, a
function, a procedure, an object method, an object implementation, an
executable application, an applet, a servlet, a shared library/dynamic load
library, a source code, an object code and/or an assembly code.
What is claimed is:

- 25 -
WE CLAIM :
1. A method to facilitate cross-paging in a multi-network communication
system, the method comprising:
obtaining communication service from a first network;
sending, by an access terminal (AT) before leaving the communication
service of the first network, an indication that resource reservation is requested.
2. The method of claim 1, wherein sending the indication that resource
reservation is requested comprises sending an indication that resource
reservation is requested for a service connection to be provided by the second
network.
3. The method of claim 2, further comprising receiving a page from the first
network for the service connection that is to be provided by the second network,
wherein sending the indication that resource reservation is requested comprises
sending the indication that resource reservation is requested after receiving the
page.
4. A method for cross-paging in a multi-network communication system, the
method comprising:
requesting, by a first network via a second network, an access terminal
(AT) for service;
establishing, by the first network, a connection with the AT to support a
communication session;
performing, by the first network prior to establishing the connection with
the AT, at least one step from the group of steps consisting of:
reserving, by the first network prior to requesting the AT for service
via the second network, at least one communication resource in anticipation of
providing service to the AT,
receiving, by the first network from the second network, information
indicating a present call state of the AT in the second network,
AMENDED PAGE

26
receiving, by the first network from the second network, cross-
paging-related configuration information for the AT, and
receiving, by the first network from the second network, an
indication that resource reservation is requested.
5. The method of claim 4, further comprising
reserving, by the first network, at least one communication resource in
anticipation of providing service to the AT, in response to receiving at least one
piece of information from the group consisting of
the information indicating the present call state of the AT in the
second network,
information indicating a location of the AT,
the cross-paging-relaled configuration information for the AT, and
the indication that resource reservation is requested.
6. The method of claim 4, wherein receiving at least one piece of
information, from the group consisting of
the information indicating the present call state of the AT in the
second network,
the cross-paging-related configuration information for the AT, and
the indication that resource reservation is requested,
comprises receiving a message from the group of messages consisting of an
event notification, a service response message, a paging response message,
and a clear request message.
7. A method for cross-paging in a multi-network communication
system, the method comprising:
providing communication service to an access terminal (AT) by a first
network;
receiving, by the first network, a message from a second network
requesting to provide communication service to the AT;
AMENDED PAGE

-27-
performing, by the first network, at least one step from the group of steps
consisting of:
sending information indicating a present call state of the AT in the
first network,
sending cross-paging-related configuration information for the AT,
and
sending an indication that resource reservation is requested.
8. A network comprising:
a transceiver;
a network interface;
a processing unit, communicatively coupled to the transceiver and the
network interface,
adapted to request, via the network interface and a second network, an access
terminal (AT) for service,
adapted to establish a connection with the AT via the transceiver to support a
communication session, and
adapted in at least one manner of adaptation from the group of adaptations
consisting of:
adapted to reserve, prior to requesting the AT for service via the second network
and prior to establishing the connection with the AT, at least one
communication resource in anticipation of providing service to the AT,
adapted to receive, from the second network via the network interface prior to
establishing the connection with the AT, information indicating a present
call state of the AT in the second network,
adapted to receive, from the second network via the network interface prior to
establishing the connection with the AT, cross-paging-related
configuration information for the AT, and
adapted to receive, from the second network via the network interface prior to
establishing the connection with the AT, an indication that resource
reservation is requested.
9. A network comprising:
AMENDED PAGE

-28-
a transceiver;
a network interface;
a processing unit, communicatively coupled to the transceiver and the
network interface,
adapted to provide communication service to an access terminal (AT) via the
transceiver,
adapted to receive a message from a second network via the network interface
requesting to provide communication service to the AT, and
adapted in at least one manner of adaptation from the group of adaptations
consisting of:
adapted to send information via the network interface indicating a present call
state of the AT,
adapted to send cross-paging-related configuration information for the AT via the
network interface, and
adapted to send an indication via the network interface that resource reservation
is requested.
10. An access terminal (AT) comprising:
a transceiver;
a processing unit, communicatively coupled to the transceiver,
adapted to obtain communication service from a first network via the transceiver,
and
adapted to send, via the transceiver before leaving the communication service of
the first network, an indication that resource reservation is requested.

Various embodiments are described which can serve to increase the cross pagin; call success rate in joint networks.
Resource reservation by a requesting network (312) in the context of cross paging is described. In general, such resource reservation
may be triggered by the occurrence of any one of a variety of events in conjunction with the requesting network determining tha. a
communication session with an AT (301) is desirable. Examples of triggering events include the following: the AT subscribing for
resource reservation as a matter of configuration, the AT having a particular call state and perhaps with regard to particular services,
the AT requesting resource reservation (before or after being paged / notified of the requesting network's desire to provide service,
the communication session for which the requesting network is requesting the AT is of a particular type, and/or resource reservation
is an operational default system operation.

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=Mfxs8yBfIgvLO2xQrPD/ZA==&loc=wDBSZCsAt7zoiVrqcFJsRw==


Patent Number 268958
Indian Patent Application Number 732/KOLNP/2008
PG Journal Number 40/2015
Publication Date 02-Oct-2015
Grant Date 24-Sep-2015
Date of Filing 19-Feb-2008
Name of Patentee MOTOROLA MOBILITY INC.
Applicant Address 1303 EAST ALGONQUIN ROAD, SCHAUMBURG, ILLINOIS
Inventors:
# Inventor's Name Inventor's Address
1 SAYEEDI, SHAHAB M 1388 HUNTER CIRCLE, NAPERVILLE, ILLINOIS 60540
2 XU, XIANG A-1501, NO. 218 HANZHONG ROAD, JS, NANJING 210029
3 CROCKER RONALD T 3N800 MEADOWRIDGE CIRCLE, ST. CHARLES, ILLINOIS 60175
PCT International Classification Number H04L 12/56
PCT International Application Number PCT/US2006/033382
PCT International Filing date 2006-08-24
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/713113 2005-08-31 U.S.A.
2 11/466537 2006-08-23 U.S.A.