U.S. patent application number 13/962358 was filed with the patent office on 2013-12-05 for methods and apparatuses for cdma2000/gprs roaming.
This patent application is currently assigned to QUALCOMM Incorporated. The applicant listed for this patent is QUALCOMM Incorporated. Invention is credited to Raymond T. Hsu, John W. Nasielski.
Application Number | 20130322410 13/962358 |
Document ID | / |
Family ID | 34681504 |
Filed Date | 2013-12-05 |
United States Patent
Application |
20130322410 |
Kind Code |
A1 |
Nasielski; John W. ; et
al. |
December 5, 2013 |
METHODS AND APPARATUSES FOR CDMA2000/GPRS ROAMING
Abstract
IIF architectures and corresponding call flows are provided for
CDMA2000/GPRS roaming scenarios such as GPRS foreign mode with
Mobile IPv4, GPRS foreign mode with Simple IPv4 or IPv6, CDMA2000
packet data foreign mode with Mobile IPv4, and CDMA2000 packet data
foreign mode with Simple IPv4 or IPv6.
Inventors: |
Nasielski; John W.; (San
Diego, CA) ; Hsu; Raymond T.; (San Diego,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
QUALCOMM Incorporated |
San Diego |
CA |
US |
|
|
Assignee: |
QUALCOMM Incorporated
San Diego
CA
|
Family ID: |
34681504 |
Appl. No.: |
13/962358 |
Filed: |
August 8, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13587349 |
Aug 16, 2012 |
8509192 |
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13962358 |
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12690584 |
Jan 20, 2010 |
8249021 |
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13587349 |
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10996425 |
Nov 23, 2004 |
7675885 |
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12690584 |
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Current U.S.
Class: |
370/335 |
Current CPC
Class: |
H04W 8/02 20130101; H04W
8/12 20130101 |
Class at
Publication: |
370/335 |
International
Class: |
H04W 8/02 20060101
H04W008/02 |
Claims
1. A method for enabling communication between a home code division
multiple access (CDMA) packet data system and a visited general
packet radio service (GPRS) system when a subscriber using mobile
internet protocol (IP) roams from the home CDMA packet data system
to the visited GPRS system, the method comprising: registering the
subscriber with the visited GPRS system over a first interface
coupling a GSM home location register emulation module to a serving
GPRS support node (SGSN) within the visited GPRS system; and
registering the subscriber with the home CDMA packet data system
over a second interface coupling an ANSI-41 visited location
register emulation module to a ANSI-41 home location register
within the home CDMA packet data system.
2. The method of claim 1, further comprising: establishing bearer
connectivity between the home CDMA packet data system and the
visited GPRS system through: a gateway GPRS support node (GGSN)
emulation module coupled to the SGSN within the visited GPRS
system; and a foreign agent (FA) emulation module coupled to a home
agent (HA) within the home CDMA packet data system.
3. The method of claim 2, further comprising: a packet routing
function between the GGSN emulation module and the FA emulation
module.
4. The method of claim 1, further comprising: mobile IP FA
challenge authentication over a third interface coupling an
authentication, authorization, and accounting (AAA) emulation
module to a AAA entity within the home CDMA packet data system.
5. The method of claim 4, further comprising: packet data
accounting over the third interface.
6. An interface entity for enabling communication between a home
code division multiple access (CDMA) packet data system and a
visited general packet radio service (GPRS) system when a
subscriber using mobile internet protocol (IP) roams from the home
CDMA packet data system to the visited GPRS system, the interface
entity comprising: a GSM home location register emulation module
allowing the subscriber to register over a first interface coupling
the GSM home location register emulation module to a serving GPRS
support node (SGSN) within the visited GPRS system; and an ANSI-41
visited location register emulation module allowing the subscriber
to register over a second interface coupling the ANSI-41 visited
location register emulation module to an ANSI-41 home location
register within the home CDMA packet data system.
7. The interface entity of claim 6, further comprising: a gateway
GPRS support node (GGSN) emulation module coupled to the SGSN
within the visited GPRS system; a foreign agent (FA) emulation
module coupled to a home agent (HA) within the home CDMA packet
data system, wherein the GGSN emulation module and the FA emulation
module support bearer connectivity between the home CDMA packet
data system and the visited GPRS system.
8. The interface entity of claim 7, further comprising: a packet
routing function between the GGSN emulation module and the FA
emulation module.
9. The interface entity of claim 7, further comprising: an
authentication, authorization, and accounting (AAA) emulation
module coupled to a AAA entity within the home CDMA packet data
system over a third interface for mobile IP FA challenge
authentication.
10. The interface entity of claim 9, wherein the AAA emulation
module coupled to the AAA entity within the home CDMA packet data
system over the third interface provides packet data
accounting.
11. A method for enabling communication between a home general
packet radio service (GPRS) system and a visited code division
multiple access (CDMA) packet data system when a subscriber using
mobile internet protocol (IP) roams from the home GPRS system to
the visited CDMA packet data system, the method comprising:
providing a home agent (HA) interface to the visited CDMA packet
data system by coupling a HA emulation module to a packet data
serving node/foreign agent (PDSN/FA) within the visited CDMA packet
data system; and providing a serving GPRS support node (SGSN)
interface to the home GPRS system by coupling a SGSN emulation
module to a gateway GPRS support node (GGSN) within the home GPRS
system, wherein a packet routing function is provided between the
SGSN emulation module and the HA emulation module.
12. The method of claim 11, further comprising: establishing bearer
connectivity between the home GPRS system and the visited CDMA
packet data system through: the HA interface; and the SGSN
interface.
13. The method of claim 12, further comprising: mobile IP
authentication over a third interface coupling an authentication,
authorization, and accounting (AAA) emulation module to a AAA
entity within the visited CDMA packet data system.
14. The method of claim 13, further comprising: packet data
accounting over the third interface.
15. The method of claim 13, further comprising: packet data
accounting over a fourth interface coupling the AAA emulation
module to a AAA entity within the home GPRS system.
16. An interface entity for enabling communication between a home
general packet radio service (GPRS) system and a visited code
division multiple access (CDMA) packet data system when a
subscriber using mobile internet protocol (IP) roams from the home
GPRS system to the visited CDMA packet data system, the interface
entity comprising: a home agent (HA) emulation module providing a
home agent interface to a packet data serving node/foreign agent
(PDSN/FA) within the visited CDMA packet data system; a SGSN
emulation module providing a SGSN interface to a gateway GPRS
support node (GGSN) within the home GPRS system, wherein a packet
routing function is provided between the SGSN emulation module and
the HA emulation module.
17. The interface entity of claim 16, further comprising: a GSM
visited location register emulation module allowing the subscriber
to register over a first interface coupling the GSM visited
location register emulation module to a GSM home location register
within the home GPRS system; and an ANSI-41 home location register
emulation module allowing the subscriber to register over a second
interface coupling the ANSI-41 home location register emulation
module to an ANSI-41 visited location register within the visited
CDMA packet data system.
18. The interface entity of claim 16, further comprising: an
authentication, authorization, and accounting (AAA) emulation
module coupled to a AAA entity within the visited CDMA packet data
system over a third interface for mobile IP authentication.
19. The interface entity of claim 18, wherein the AAA emulation
module coupled to the AAA entity within the visited CDMA packet
data system over the third interface provides packet data
accounting.
20. The interface entity of claim 18, further comprising: the AAA
emulation module coupled to a AAA entity within the home GPRS
system over a fourth interface for packet data accounting.
21. A method for enabling communication between a home general
packet radio service (GPRS) system and a visited code division
multiple access (CDMA) packet data system when a subscriber using
simple internet protocol (IP) roams from the home GPRS system to
the visited CDMA packet data system, the method comprising:
providing a layer 2 tunneling protocol network server (LNS)
interface to the visited CDMA packet data system by coupling a LNS
emulation module to a packet data serving node/layer 2 tunneling
protocol Access Concentrator (PDSN/LAC) within the visited CDMA
packet data system; and providing a serving GPRS support node
(SGSN) interface to the home GPRS system by coupling a SGSN
emulation module to a gateway GPRS support node (GGSN) within the
home GPRS system, wherein a packet routing function is provided
between the SGSN emulation module and the home agent emulation
module.
22. The method of claim 21, further comprising: establishing bearer
connectivity between the home GPRS system and the visited CDMA
packet data system through: the LNS interface; and the SGSN
interface.
23. The method of claim 21, further comprising: layer 2 tunneling
protocol (L2TP) authentication over a third interface coupling an
authentication, authorization, and accounting (AAA) emulation
module to a AAA entity within the visited CDMA packet data
system.
24. The method of claim 23, further comprising: packet data
accounting over the third interface.
25. The method of claim 23, further comprising: packet data
accounting over a fourth interface coupling the AAA emulation
module to a AAA entity within the home GPRS system.
26. An interface entity for enabling communication between a home
general packet radio service (GPRS) system and a visited code
division multiple access (CDMA) packet data system when a
subscriber using simple internet protocol (IP) roams from the home
GPRS system to the visited CDMA packet data system, the interface
entity comprising: a L2TP network server (LNS) emulation module
providing a LNS interface to a packet data serving node/layer 2
tunneling protocol Access Concentrator (PDSN/LAC) within the
visited CDMA packet data system; a SGSN emulation module providing
a SGSN interface to a gateway GPRS support node (GGSN) within the
home GPRS system, wherein a packet routing function is provided
between the SGSN emulation module and the home agent emulation
module.
27. The interface entity of claim 26, further comprising: a GSM
visited location register emulation module allowing the subscriber
to register over a first interface coupling the GSM visited
location register emulation module to a GSM home location register
within the home GPRS system; and an ANSI-41 home location register
emulation module allowing the subscriber to register over a second
interface coupling the ANSI-41 home location register emulation
module to an ANSI-41 visited location register within the visited
CDMA packet data system.
28. The interface entity of claim 27, further comprising: an
authentication, authorization, and accounting (AAA) emulation
module coupled to a AAA entity within the visited CDMA packet data
system over a third interface for L2TP authentication.
29. The interface entity of claim 28, wherein the AAA emulation
module is coupled to the AAA entity within the visited CDMA packet
data system for packet data accounting.
30. The interface entity of claim 28, further comprising: the AAA
emulation module coupled to a AAA entity within the home GPRS
system over a fourth interface for packet data accounting.
31. A method for enabling communication between a home code
division multiple access (CDMA) packet data system and a visited
general packet radio service (GPRS) system when a subscriber using
simple internet protocol (IP) roams from the home CDMA packet data
system to the visited GPRS system, the method comprising: coupling
the home CDMA packet data system to the visited GPRS system by
providing a distinct interface for each of an ANSI-41 home location
register, an authentication, authorization, and accounting (AAA)
entity, and a layer 2 tunneling protocol network server (LNS)
within the home CDMA packet data system.
32. The method of claim 31, wherein the coupling the home CDMA
packet data system to the visited GPRS system further includes
providing a distinct interface for a Serving GPRS Service Node
(SGSN) within the visited GPRS system.
33. The method of claim 32, further comprising: registering the
subscriber with the visited GPRS system over the distinct interface
for the SGSN within the visited GPRS system; and registering the
subscriber with the home CDMA packet data system over the distinct
interface for the ANSI-41 home location register within the home
CDMA packet data system.
34. The method of claim 32, further comprising: establishing bearer
connectivity between the home GPRS system and the visited CDMA
packet data system through: the distinct interface for the SGSN;
and the distinct interface for the ANSI-41 home location
register.
35. The method of claim 31, further comprising: layer 2 tunneling
protocol (L2TP) authentication and packet data accounting over the
distinct interface for the AAA entity.
36. A method for enabling communication between a home code
division multiple access (CDMA) packet data system and a visited
general packet radio service (GPRS) system when a subscriber using
simple internet protocol (IP) roams from the home CDMA packet data
system to the visited GPRS system, the method comprising:
registering the subscriber with the visited GPRS system over a
first interface coupling a GSM home location register to a serving
GPRS support node (SGSN) within the visited GPRS system; and
registering the subscriber with the home CDMA packet data system
over a second interface coupling an ANSI-41 visited location
register to a ANSI-41 home location register within the home CDMA
packet data system.
37. The method of claim 36, further comprising: establishing bearer
connectivity between the home CDMA packet data system and the
visited GPRS system through: a gateway GPRS support node (GGSN)
emulation module coupled to the SGSN within the visited GPRS
system; and a layer 2 tunneling protocol Access Concentrator (LAC)
emulation module coupled to a layer 2 tunneling protocol network
server (LNS) within the home CDMA packet data system.
38. The method of claim 37, further comprising: a packet routing
function between the GGSN emulation module and the LAC emulation
module.
39. The method of claim 36, further comprising: layer 2 tunneling
protocol (L2TP) authentication over a third interface coupling an
authentication, authorization, and accounting (AAA) emulation
module to a AAA entity within the home CDMA packet data system.
40. The method of claim 39, further comprising: packet data
accounting over the third interface.
41. An interface entity for enabling communication between a home
code division multiple access (CDMA) packet data system and a
visited general packet radio service (GPRS) system when a
subscriber using simple internet protocol (IP) roams from the home
CDMA packet data system to the visited GPRS system, the interface
entity comprising: a GSM home location register allowing the
subscriber to register over a first interface coupling the GSM home
location register to a serving GPRS support node (SGSN) within the
visited GPRS system; and an ANSI-41 visited location register
allowing the subscriber to register over a second interface
coupling the ANSI-41 visited location register to an ANSI-41 home
location register within the home CDMA packet data system.
42. The interface entity of claim 41, further comprising: a gateway
GPRS support node (GGSN) emulation module coupled to the SGSN
within the visited GPRS system; a layer 2 tunneling protocol Access
Concentrator (LAC) emulation module coupled to a L2TP network
server (LNS) within the home CDMA packet data system, wherein the
GGSN emulation module and the FA emulation module support bearer
connectivity between the home CDMA packet data system and the
visited GPRS system.
43. The interface entity of claim 42, further comprising: a packet
routing function between the GGSN emulation module and the LAC
emulation module.
44. The interface entity of claim 42, further comprising: an
authentication, authorization, and accounting (AAA) emulation
module coupled to a AAA entity within the home CDMA packet data
system for L2TP authentication.
45. The interface entity of claim 44, wherein the AAA emulation
module coupled to the AAA entity within the home CDMA packet data
system provides packet data accounting.
Description
CLAIM OF PRIORITY UNDER 35 U.S.C. .sctn.119
[0001] The present application for patent is a continuation of and
claims priority to application Ser. No. 13/587,349 filed Aug. 16,
2012 entitled "METHODS AND APPARATUSES FOR CDMA2000/GPRS ROAMING",
and assigned to the assignee hereof. The disclosure of the prior
application is considered part of, and is incorporated by reference
in, this disclosure. The prior application for patent is a
continuation of and claims priority to U.S. Pat. No. 8,249,021
filed Jan. 20, 2010 entitled "METHOD AND APPARATUSES FOR
CDMA2000/GPRS ROAMING", and assigned to the assignee hereof. The
disclosure of the prior application is considered part of, and is
incorporated by reference in, this disclosure. U.S. Pat. No.
8,249,021 is a continuation of and claims priority to U.S. Pat. No.
7,675,885 filed Nov. 23, 2004 entitled "METHODS AND APPARATUSES FOR
CDMA2000/GPRS ROAMING", and assigned to the assignee hereof. The
disclosure of U.S. Pat. No. 7,675,885 is considered part of, and is
incorporated by reference in, this disclosure. U.S. Pat. No.
7,675,885 claims priority to Provisional Application No. 60/526,557
entitled "CDMA/GPRS Packet Data Roaming" filed Dec. 3, 2003, and
assigned to the assignee hereof. Provisional Application No.
60/526,557 is hereby expressly incorporated by reference
herein.
BACKGROUND
[0002] 1. Field
[0003] The present disclosed embodiments relate generally to
wireless communications, and more specifically to roaming in the
context of CDMA2000 and GPRS systems.
[0004] 2. Background
[0005] Wireless subscribers may desire to use their wireless
terminals in conjunction with wireless systems other than their
home systems to obtain access to services using their existing
subscriptions. Access to these services may be independent of their
normal wireless terminals, through wireless systems other than
their home systems. This may occur, for example, when the
subscriber is roaming outside the service area of their home
system. Accordingly, manufacturers and system operators desire to
allow subscribers to receive services using their terminals and
subscriptions via a system which may not be the subscriber's home
system, provided that the terminal and the serving system are
compatible.
[0006] Serving roaming subscribers can be difficult even when the
serving system and home system employ identical technologies. When
the serving system uses an air interface that differs from that
used in the subscriber's home system, interworking between these
systems is typically performed due to fundamental differences in
message protocols, call models, et cetra. This interworking can be
achieved via an Interworking and Interoperability Function
(IIF).
[0007] One example of an IIF is described in US Patent Application
2002/094811 A1 to Bright et al. entitled "Interworking and
Interoperability of GPRS Systems With Systems of Other Technology
Families." US Patent Application 2002/094811 A1 provides a GPRS
interworking and interoperability function (IIF) interposed between
a serving GSM/GPRS wireless system and a second wireless system of
a different technology family. The IIF allows a mobile station
homed to the second wireless system to operate in the GSM/GPRS
system. According to US Patent Application 2002/094811 A1,
telecommunications system components are provided that allow
interworking and interoperability of a serving GSM and/or GPRS
system with certain "domestic wireless" systems. For example, a
mobile station homed on such a domestic wireless system, but
registered with the serving system in a GPRS-only mode, may receive
services from the serving system. US Patent Application 2002/094811
A1 mentions that the term "domestic wireless" (DW) is intended to
refer to non-GSM systems compatible with ANSI or equivalent
standards for TDMA, CDMA, and analog cellular systems, as generally
used in North America, or compatible with other similar
systems.
[0008] Although US Patent Application 2002/094811 A1 acknowledges
the need for an IIF allows a mobile station homed to a CDMA
wireless system to operate in the GSM/GPRS system, US Patent
Application 2002/094811 A1 does not discuss an IIF adapted for
CDMA2000/GPRS roaming scenarios when the terminal is using Mobile
IP or Simple IP. US Patent Application 2002/094811 A1 fails to
provide sufficient information, direction or guidance regarding how
an IIF could be constructed that would allow a mobile station homed
to a CDMA2000 wireless system could operate in the GSM/GPRS system,
when the terminal is using Mobile IP or Simple IP. For example, US
Patent Application 2002/094811 A1 fails to provide any details
regarding what modules would be needed to implement such an IIF,
how the modules would be interconnected, timed and controlled so as
to obtain the specific operations needed to implement such an
IIF.
[0009] Thus, there is a need in the art for a general architecture
can be adapted for CDMA2000/GPRS roaming scenarios, such as, GPRS
foreign mode with Mobile IPv4, GPRS foreign mode with Simple IPv4
or IPv6, CDMA2000 packet data foreign mode with Mobile IPv4, and
CDMA2000 packet data foreign mode with Simple IP, Mobile IPv4 or
Mobile IPv6. It would be desirable to enable communication between
a CDMA 2000 packet data system and a GPRS system, when a CDMA 2000
packet data native subscriber using Simple IP, Mobile IPv4 or
Mobile IPv6 roams to the GPRS system by supporting bearer
connectivity between the GPRS and CDMA 2000 packet data system.
Similarly, it would also be desirable to enable communication
between a GPRS system and a CDMA 2000 packet data system when a
GPRS native subscriber roams from the GPRS system to the CDMA 2000
packet data system using Simple IP, Mobile IPv4 or Mobile IPv6 by
supporting bearer connectivity between the GPRS system and the CDMA
2000 packet data system.
SUMMARY
[0010] According to one aspect of the invention, an interface
entity, interposed between a CDMA 2000 packet data system and a
GPRS system, is provided that enables communication between the
CDMA 2000 packet data system and the GPRS system when a CDMA 2000
packet data native subscriber roams to the GPRS system by
supporting bearer connectivity between the GPRS and CDMA 2000
packet data system by providing a packet routing function.
[0011] According to one aspect of the invention, an interface
entity is provided that enables communication between a home CDMA
2000 packet data system and a visited GPRS system comprising a
SGSN, when a CDMA 2000 packet data native subscriber using Mobile
IPv4 roams to a visited GPRS system.
[0012] For example, in an embodiment where a CDMA 2000 packet data
native subscriber roams to a visited system and uses Mobile IPv4,
an interface entity can be provided that couples the home system to
the visited system to enable communication between the home system
and the visited system. In this situation, the home system is a
CDMA 2000 packet data system that can include a ANSI-41 home
location register; an AAA entity; and a home agent, whereas the
visited system can be a GPRS system that includes a SGSN.
[0013] According to one aspect of this embodiment, the interface
comprises a GSM home location register emulation module, and an
ANSI-41 visited location register emulation module. The GSM home
location register emulation module can be coupled to the SGSN via a
Gr interface, that allows a subscriber to register over a Gr
interface, whereas the ANSI-41 visited location register emulation
module can be coupled to the ANSI-41 home location register via a D
interface that allows a subscriber to register over the D
interface. According to one aspect of this embodiment, the
interface further comprises a foreign agent emulation module and a
GGSN emulation module. The foreign agent emulation module can be
coupled to the home agent via an X1 interface, and supports bearer
connectivity between the visited system and the home system such
that a foreign agent interface and an AAA interface are presented
to the CDMA 2000 packet data system over the X1 interface. The GGSN
emulation module can be coupled to the SGSN via a Gp interface, and
can support bearer connectivity between the visited system and the
home system such that a GGSN interface is presented to the visited
system over the Gp interface. The interface can serve as an
endpoint for a GTP tunnel and a Mobile IP tunnel. In this
embodiment, the interface provides a packet routing function
between the GGSN interface and the foreign agent interface.
According to another aspect of this embodiment, the interface can
also include an AAA emulation module that can be coupled to the AAA
entity via an X3 interface. In this embodiment, the AAA emulation
module provides an accounting function to interacting with a home
network's AAA for Mobile IP Foreign Agent challenge authentication
and 3GPP2 packet data accounting.
[0014] According to one aspect of the invention, an interface
entity is provided that enables communication between a home CDMA
2000 packet data system and a visited GPRS system comprising a
SGSN, when a CDMA 2000 packet data native subscriber using Simple
IP roams to a visited GPRS system.
[0015] In an embodiment where a CDMA 2000 packet data native
subscriber roams to a visited system and uses Simple IP, an
interface entity can be provided that couples the home system to
the visited system to enable communication between the home system
and the visited system. In this situation, the home system is a
CDMA 2000 packet data system that can include a ANSI-41 home
location register; an AAA entity; and a LNS, whereas the visited
system can be a GPRS system that includes a SGSN.
[0016] According to one aspect of this embodiment, the interface
comprises an ANSI-41 visited location register, and a GSM home
location register. The ANSI-41 visited location register can be
coupled to the ANSI-41 home location register via a D interface,
and allows a subscriber to register over the D interface. The GSM
home location register can be coupled to the SGSN via a Gr
interface and allows a subscriber to register over the Gr
interface. According to another aspect of this embodiment, the
interface may comprise a LAC emulation module and a GGSN emulation
module. The LAC emulation module can be coupled to the LNS via an
X2 interface, and supports bearer connectivity between the visited
and home networks over the X2 interface. The GGSN emulation module
can be coupled to the SGSN via a Gp interface, and supports bearer
connectivity between the visited and home networks over the Gp
interface by presenting a GGSN interface to the visited system and
presenting a normal routing interface to the CDMA 2000 packet data
system to thereby provide a packet routing function between the
GGSN interface and the home system. In this case, the interface
serves as an endpoint for a GTP tunnel and an IPSec tunnel.
According to yet another aspect of this embodiment, the interface
can include an AAA emulation module that can be coupled to the AAA
entity via an X3 interface. The AAA emulation module can provide an
accounting function by interacting with the home network's AAA for
L2TP authentication and 3GPP2 packet data accounting over the X3
interface.
[0017] According to another aspect of the invention, an interface
entity, interposed between a GPRS system to a CDMA 2000 packet data
system, is provided that enables communication between the GPRS
system and the CDMA 2000 packet data system when a GPRS native
subscriber roams from the GPRS system to a CDMA 2000 packet data
system using one of Mobile IPv4 and Simple IP by supporting bearer
connectivity between the GPRS system and the CDMA 2000 packet data
system by providing a packet routing function.
[0018] According to yet another aspect of the invention, an
interface entity is provided that enables communication between a
home GPRS system comprising a GSM home location register, a GGSN,
and an AAA entity, and a visited CDMA 2000 packet data system that
comprises an ANSI-41 visited location register, an AAA entity, and
a packet data serving node/foreign agent, when a GPRS native
subscriber using Mobile IPv4 roams to the visited CDMA 2000 packet
data system.
[0019] In an embodiment where a GPRS native subscriber roams to a
visited system and uses Mobile IPv4, an interface entity can be
provided that couples the home system to the visited system to
enable communication between the home system and the visited
system. In this situation, the home system is a GPRS system
comprising a GSM home location register; a GGSN; and an AAA entity,
whereas the visited system can comprise a CDMA 2000 packet data
system that includes a ANSI-41 visited location register; a AAA
entity; and a packet data serving node/foreign agent.
[0020] According to one aspect of this embodiment, the interface
comprises a home agent emulation module and a SGSN emulation
module. The home agent emulation module can be coupled to the
packet data serving node/foreign agent via an X1 interface, and
presents a home agent interface to the visited system. The SGSN
emulation module can be coupled to the GGSN via a Gp interface, and
presents a SGSN interface to the home system to support bearer
connectivity between the visited and home networks by providing a
packet routing function between the SGSN interface and the home
agent interface. Here, the interface serves as an endpoint for a
GTP tunnel and a Mobile IP tunnel. According to another aspect of
this embodiment, the interface can also include an ANSI-41 home
location register emulation module, and a GSM visited location
register emulation module. The ANSI-41 home location register
emulation module can be coupled to the ANSI-41 visited location
register via a D interface, whereas the GSM visited location
register emulation module can be coupled to the GSM home location
register via a D interface, to allow a subscriber to register.
According to yet another aspect of this embodiment, the interface
may also include an AAA emulation module that can be coupled to the
AAA entity via a Gi interface and coupled to the AAA entity via a
X3 interface. The AAA emulation module interacts with the visited
network's AAA for Mobile IP authentication and 3GPP2 packet data
accounting, over the X3 interface, and the home network's AAA for
3GPP packet data accounting, over the Gi interface.
[0021] According to one aspect of the invention, an interface
entity is provided that enables communication between a home GPRS
system comprising a GSM home location register, a GGSN, and an AAA
entity, and a visited CDMA 2000 packet data system that comprises
an ANSI-41 visited location register, an AAA entity, and a packet
data serving node/LAC entity, when a GPRS native subscriber using
Simple IP roams to the visited CDMA 2000 packet data system.
[0022] In an embodiment where a GPRS native subscriber roams to a
visited system and uses Simple IP, an interface entity can be
provided that couples the home system to the visited system to
enable communication between the home system and the visited
system. In this situation, the home system is a GPRS system
comprising a GSM home location register; a GGSN; and an AAA entity,
whereas the visited system can comprise a CDMA 2000 packet data
system that includes a ANSI-41 visited location register; a AAA
entity; and a packet data serving node/LAC entity. According to one
aspect of the invention, the interface supports bearer connectivity
between the visited and home networks by providing a packet routing
function. For example, the interface can include a SGSN emulation
module, and a LNS emulation module. The SGSN emulation module can
be coupled to the GGSN over a Gp interface, and presents a SGSN
interface to the home system, whereas the LNS emulation module can
be coupled to the packet data serving node/LAC entity over an X2
interface, and presents a L2TP Network Server (LNS) interface to
the visited system. As such, this interface provides the packet
routing function between the SGSN emulation module and the LNS
emulation module. Here, the interface serves as an endpoint for a
GTP tunnel and a Mobile L2TP tunnel.
[0023] According to another aspect of this embodiment, the
interface comprises a ANSI-41 home location register emulation
module and a GSM visited location register emulation module. The
ANSI-41 home location register emulation module can be coupled to
the ANSI-41 visited location register via a D interface, whereas
the GSM visited location register emulation module can be coupled
to the GSM home location register via another D interface. This
allows a subscriber to register. According to yet another aspect of
this embodiment, the interface may also include an AAA emulation
module that can be coupled to the AAA entity via a Y3 interface and
coupled to the AAA entity via a X3 interface. The AAA emulation
module interacts with the visited network's AAA entity, over an X3
interface, for L2TP authentication and 3GPP2 packet data
accounting, and with the home network's AAA entity, over an Gi
interface, for 3GPP packet data accounting.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a block diagram of a system that comprises a home
system, a visited system, and an interface entity that enables
communication between the home system and the visited system;
[0025] FIG. 2A is a block diagram of GPRS foreign mode with Mobile
IPv4;
[0026] FIG. 2B is a call flow diagram that shows Mobile IPv4
operation in the GPRS foreign mode;
[0027] FIG. 3A is a block diagram of GPRS foreign mode with Simple
IP;
[0028] FIG. 3B is a call flow diagram that shows Simple IP
operation in the GPRS foreign mode;
[0029] FIG. 4A is a block diagram of CDMA2000 packet data foreign
mode with Mobile IPv4;
[0030] FIG. 4B is a call flow diagram that shows Mobile IPv4
operation in the CDMA2000 packet data foreign mode;
[0031] FIG. 5A is a block diagram of CDMA2000 packet data foreign
mode with Simple IP; and
[0032] FIG. 5B is a call flow diagram that shows Simple IP
operation in the CDMA2000 packet data foreign mode.
DETAILED DESCRIPTION
[0033] The word "exemplary" can be used herein to mean "serving as
an example, instance, or illustration." Any embodiment described
herein as "exemplary" can be not necessarily to be construed as
preferred or advantageous over other embodiments.
[0034] FIG. 1 is a block diagram of a system that comprises a home
system 10, such as a CDMA 2000 packet data system or a GPRS system,
a visited system 20, such as a GPRS system or a CDMA 2000 packet
data system, and an interface entity 30 or "IIF" that couples the
home system 10 to the visited system 20, and enables communication
between the home system 10 and the visited system 20.
[0035] The following sections describe architectures that can be
adapted for CDMA2000/GPRS roaming scenarios, such as, GPRS foreign
mode with Mobile IPv4, GPRS foreign mode with Simple IPv4 or IPv6,
CDMA2000 packet data foreign mode with Mobile IPv4, and CDMA2000
packet data foreign mode with Simple IPv4 or IPv6.
[0036] GPRS Foreign Mode with Mobile IPv4
[0037] FIG. 2A is an exemplary block diagram of a GPRS foreign mode
with Mobile IPv4, and depicts the functions and control interface
provided by an IIF in this embodiment. This roaming scenario occurs
when a CDMA2000 packet data native subscriber operates Mobile IPv4
[IS-835-C] in GPRS foreign mode. In this embodiment, the home
system 10 can be a CDMA 2000 packet data system wherein a CDMA 2000
packet data native subscriber roams to a GPRS system and uses
Mobile IPv4. The home system 10 comprises a ANSI-41 home location
register 131, an AAA entity 116, and a home agent 135. The visited
system 20 can be a GPRS system that comprises a SGSN 137.
[0038] The interface 30 or "IIF" comprises an ANSI-41 visited
location register 111 coupled to the ANSI-41 home location register
131 via a D interface 113, a GSM home location register 124 coupled
to the SGSN 137 via a Gr interface 123, a GGSN 126 coupled to the
SGSN 137 via a Gp interface 127 and coupled to the Internet via a
Gi interface, an AAA entity 140 coupled to the AAA entity 116 via
an X3 interface 117, and a foreign agent 118 coupled to the home
agent 135 via an X1 interface 115. The IIF provides both GSM HLR
and ANSI-41 VLR emulation to allow the subscriber to register. This
interworking can be provided over the interface references "Gr" and
"D". The IIF provides GGSN and FA emulation to support bearer
connectivity between the visited and home networks via the IIF.
This interworking can be provided over the interface references
"Gn" and "X1". The IIF provides AAA emulation to interact with the
home network's AAA for Mobile IP Foreign Agent challenge
authentication and 3GPP2 packet data accounting. This interworking
can be provided over the interface reference "X3".
[0039] If bearer connectivity between from the GPRS system and the
CDMA2000 packet data system is not required, then reverse tunneling
on the X1 interface is not required. Rather, MS-terminated traffic
traverses through the X1 and Gp interfaces. In the case where
reverse tunneling is not required, the IIF routes MS-originated
traffic, received on a Gp interface, to the Internet directly via a
Gi interface.
[0040] Thus, for a user homed in a CDMA Mobile IP system roaming to
a GSM system, the IIF may present a GGSN interface to GSM and a FA
and AAA interfaces to the CDMA system. The IIF may serve as the
endpoint for the GTP and Mobile IP tunnels, with a packet routing
function between the GGSN and FA. The IIF may also provide an
accounting function so that operators can charge based on
configurable measurements such as packet count, bandwidth, time of
day, etc.
[0041] FIG. 2B is an exemplary call flow diagram that shows Mobile
IPv4 operation in the GPRS foreign mode. FIG. 2B depicts a call
flow example for the roaming scenario where a CDMA2000 packet data
native subscriber operates Mobile IPv4 [IS-835-C] in the GPRS
foreign mode. In this example, the MS has shared secrets with the
home CDMA2000 system for Mobile IP authentication. The MS may
request the home CDMA2000 system to assign a HA and/or an IP
address. The reverse tunneling can be enabled so that all data
traffic (MS-originated and -terminated) traverses through the IIF
and home CDMA2000 system. The IIF generates 3GPP2 packet data
accounting records and sends it to the home CDMA2000 system via
RADIUS.
[0042] The MS performs GPRS attach with a SGSN. The authentication
associated with the GPRS attach can be a SIM-based authentication
requiring the Ki secret key. The IIF acts as the GSM HLR configured
with the Ki secret. In any case, the IIF can be not required to
communicate with the HLR in the home CDMA2000 system for the
authentication. (Step 1) The MS sends the Activate PDP Context
Request to the SGSN. The message includes the Access Point Name
(APN). The APN has the format <Network
ID>.<MNC>.<MCC>.gprs. The Network ID (e.g.,
CDMA2000carrier.com) indicates to which external network the MS
wants to establish a logical connection. The Requested PDP Address
can be omitted in the message. The MS has a static Mobile IP home
address or obtains a new Mobile IP home address. (Step 2) The SGSN
selects a GGSN based on the APN. The SGSN uses the APN as the
lookup name to query a DNS server (not shown in the figure) and
obtains a list of available GGSNs that can be used to support the
requested APN. The APN's Network ID indicates a CDMA2000 operator;
thus, the DNS server returns with the IIF's IP address. (Step 3)
The SGSN sends the Activate PDP Context Request to the selected IIF
to set up a PDP context for the MS. The message includes the APN,
but the Requested PDP Address can be omitted. (Step 4) The IIF acts
as the GGSN and sends the Create PDP Context Response to the SGSN
that in turn sends the Activate PDP Context Accept to the MS. The
PDP Address in both messages can be set to 0.0.0.0 to indicate that
the PDP address will be assigned later after successful Mobile IP
registration. (Step 5) The IIF acts as the FA and sends one or more
Mobile IP Agent Advertisements to the MS, because the omission of
the Requested PDP Address in the Activate PDP Context Request can
be the indication that the MS wishes to use Mobile IP. The Agent
Advertisement can be sent over the established PDP context. The
Agent Advertisement contains the FA Care-of Address and the FA
Challenge (FAC). (Step 6)
[0043] The MS sends the Mobile IP Registration Request to the IIF
over the PDP context. The following information can be contained in
the Registration Request: MS's NAI [RFC 2794] has the format of
<username>@<domain_name>, where the domain_name
identifies the MS's home CDMA2000 system. MS-HA authenticator can
be computed based on the content of the Registration Request and
the secret shared between the MS and HA [RFC 2002]. MS-AAA
authenticator can be computed based on the FAC and the secret
shared between the MS and home AAA server [RFC 3012]. The HA
Address field can be set to a known value if the MS uses a
permanent HA, or to 0.0.0.0 if the MS wants a new HA assigned by
the home network. Home Address field can be set to a known value if
the MS uses a permanent address, or to 0.0.0.0 if the MS wants a
new address assigned by the HA. The T-bit can be set to one to
enable a reverse tunnel from the IIF to the MS's HA. (Step 7) The
IIF acts as the RADIUS client and sends a RADIUS Access-Request to
the home AAA server. The RADIUS Access-Request conveys MS's NAI,
FAC authenticator, FAC, HA address, etc. [IS-835]. (Step 8) If the
authentication is successful, the home AAA server responds with the
RADIUS Access-Accept that includes the MS's HA address. (Step 9)
The IIF acts as the FA and forwards the Mobile IP Registration
Request to the HA address contained in the RADIUS Access-Accept.
(Step 10) The HA verifies the MS-HA authenticator in the Mobile IP
Registration Request. If the HA doesn't have the shared secret, as
in the case of dynamically assigned HA, it communicates with the
home AAA server for the shared secret. The HA responds to the
Mobile IP Registration Request with the Mobile IP Registration
Reply containing a registration result (e.g., successful or an
error code). If the MS wishes for a new home address, a new address
can be returned in the Registration Reply; otherwise, the MS's
permanent address can be returned. (Step 11) The IIF acts as the FA
and forwards the Mobile IP Registration Reply to the MS over the
appropriate PDP context. The IIF FA functionality notes the
assigned MS IP address and shares that address with the IIF GGSN
functionality. (Step 12)
[0044] The IIF acts as the GGSN and updates its PDP context by
setting the PDP address to the MS's home address (as indicated in
the Registration Reply and shared by the FA functionality). The PDP
address (hence the MS's home address) can be associated with a GTP
tunnel identified by the Tunnel Endpoint ID (TEID). (Step 13) The
IIF acts as the GGSN and triggers the GGSN-initiated PDP Context
modification procedure in order to update the PDP address in the
SGSN and MS [3GPP TS 29.061]. The IIF sends the Update PDP Context
Request to the SGSN that forwards it to the MS. (Step 14) The MS
responds with the Update PDP Context Response to the SGSN that
forwards it to the IIF. (Step 15) The IIF acts as the RADIUS client
and sends the RADIUS Accounting-Request (Start) to the home AAA
server [IS-835]. 3GPP2-vendor-specific attributes are used to
convey accounting records, but some airlink record attributes
(e.g., service option, mux option, etc.) are not applicable. (Step
16) The home AAA server responds with a RADIUS Accounting-Response
(Start). (Step 17) Bearer traffic traverses through the IIF in both
directions, if reverse tunneling from the IIF to HA is enabled. For
routing MS-originated packets, the IIF routes packets received from
the MS's GTP tunnel (identified by a TEID) to the MS's HA via a
Mobile IP reverse tunnel. For routing MS-terminated packets, the
IIF routes packets received from the HA-to-FA tunnel to the MS's
GTP tunnel. IPsec can be used to protect the Mobile IP tunnels
between HA and IIF, and the GTP tunnels between IIF and SGSN. (Step
18)
[0045] GPRS Foreign Mode with Simple IP
[0046] FIG. 3A is an exemplary block diagram of a GPRS foreign mode
with Simple IP that shows a roaming scenario where a CDMA2000
packet data native subscriber operates IPv4 or IPv6 in the GPRS
foreign mode. FIG. 3A also depicts the functions and control
interface provided by an interface or IIF in this case. In this
embodiment, the home system 10 can be a CDMA 2000 packet data
system wherein a CDMA 2000 packet data native subscriber roams to a
GPRS system and uses Simple IP. The home system 10 comprises a
ANSI-41 home location register 131, an AAA entity 116, and a LNS
139. The visited system 20 can be a GPRS system that comprises a
SGSN 137.
[0047] The interface 30 or "IIF" comprises an ANSI-41 visited
location register 111 coupled to the ANSI-41 home location register
131 via a D interface 113, a GSM home location register 124 coupled
to the SGSN 137 via a Gr interface 123, a GGSN 126 coupled to the
SGSN 137 via a Gp interface 127 and coupled to the Internet via a
Gi interface, an AAA entity 140 coupled to the AAA entity 116 via
an X3 interface 117, and a LAC entity 109 coupled to the LNS 139
via an X2 interface 119. The IIF provides both GSM HLR and ANSI-41
VLR emulation to allow the subscriber to register. This
interworking can be provided over the interface references "Gr" and
"D." The IIF provides GGSN and LAC emulation to support bearer
connectivity between the visited and home networks via the IIF.
This interworking can be provided over the interface references
"Gn" and "X2." The IIF provides AAA emulation to interact with the
home network's AAA for L2TP authentication and 3GPP2 packet data
accounting. This interworking can be provided over the interface
reference "X3."
[0048] If bearer connectivity between the CDMA2000 packet data
system and GPRS system is not required, then the X2 interface is
not required. The IIF still supports a Gp interface to the SGSN and
provides Internet access via a Gi interface (not shown in the
figure).
[0049] Thus, for a user homed in a CDMA Simple IP system roaming to
a GSM system, the IIF may present a GGSN interface to GSM and a
normal routing interface to the CDMA system. The IIF may serve as
the endpoint for the GTP and IPSec tunnels, with a packet routing
function between the GGSN and the CDMA system. The IIF may also
provide an accounting function so that operators can charge based
on configurable measurements such as packet count, bandwidth, time
of day, etc.
[0050] FIG. 3B is an exemplary call flow diagram that shows Simple
IP operation in the GPRS foreign mode, and explains a roaming
scenario where a CDMA2000 packet data native subscriber operates
Simple IP in the GPRS foreign mode. In this example, the MS has
shared secrets with the home CDMA2000 system for Simple IP
authentication (i.e., CHAP). The MS establishes a PPP session, via
L2TP, to the home CDMA2000 system. During the PPP establishment,
the home CDMA2000 system assigns an IP address to the MS
dynamically. All the MS's data traffic (MS-originated and -MS
terminated) traverses through the IIF and home CDMA2000 system. The
IIF generates 3GPP2 packet data accounting records and sends it to
the home CDMA2000 system via RADIUS.
[0051] The MS performs GPRS attach with a SGSN. The authentication
associated with the GPRS attach can be a SIM-based authentication
requiring the Ki secret. The IIF acts as the GSM HLR configured
with the Ki secret or the GSM VLR. In any case, the IIF can be not
required to communicate with the HLR in the home CDMA2000 system
for the authentication. (Step 1) The MS sends the Activate PDP
Context Request to the SGSN. The message includes the APN (Access
Point Name). The APN has the format <Network
ID>.<MNC>.<MCC>.gprs. The Network ID (e.g.,
CDMA2000carrier.com) indicates to which external network the MS
wants to establish a logical connection. The Requested PDP Address
can be omitted in the message so that the IIF (acting as a GGSN)
later will not assign an IP address to the MS; instead, the address
will be assigned by the LNS. (Step 2) The SGSN selects a GGSN based
on the APN. The SGSN queries a DNS server (not shown in the figure)
and obtains a list of available GGSNs that can be used to support
the requested APN. In this case, the APN's Network ID indicates a
CDMA2000 operator; thus, the DNS server returns with the IIF's IP
address. (Step 3)
[0052] The SGSN sends the Activate PDP Context Request to the
selected IIF to set up a PDP context for the MS. The message
includes the APN, but the Requested PDP Address can be omitted.
(Step 4) The IIF acts as the GGSN and sends the Create PDP Context
Response to the SGSN that in turn sends the Activate PDP Context
Accept to the MS. The PDP Address in both messages can be set to
0.0.0.0 to indicate that the PDP address will be reset later. (Step
5)
[0053] After the PDP context can be established, the MS and IIF
perform PPP LCP negotiation. The IIF LAC functionality establishes
L2TP tunnels with a LNS. The IIF determines which LNS based on the
requested APN. The IIF is configured with the LNS information
(e.g., LNS's IP address) corresponding to an APN. After the L2TP
tunnel establishment, the IIF LAC functionality forwards LCP
information between the LNS and MS. During the LCP negotiation, the
LNS and MS negotiate PAP or CHAP as the protocol for PPP
authentication. (Step 6) PPP authentication (PAP or CHAP) is
performed. The MS's credential is authenticated by the home AAA in
the CDMA2000 system. The RADIUS interaction between the LNS and
home AAA is not shown in the figure. (Step 7) The LNS and MS
perform PPP IPCP negotiation. The IIF LAC functionality relays IPCP
messages between the L2TP tunnel and PDP context. During the
negotiation, the LNS assigns an IP address to the MS. The IIF
monitors for this address and uses it as the MS's PDP address.
(Step 8)
[0054] The IIF also needs to notify the SGSN and MS about the
updated PDP address. Recall that the PDP address can be set to
0.0.0.0 initially. Therefore, the IIF sends the Update PDP Context
Request to the SGSN that forwards it to the MS. (Step 9) The MS
responds with the Update PDP Context Response to the SGSN that
forwards it to the IIF. (Step 10)
[0055] The IIF acts as the RADIUS client and sends the RADIUS
Accounting-Request (Start) to the home AAA server [IS-835].
3GPP2-vendor-specific attributes are used to convey accounting
records, but some airlink record attributes (e.g., service option,
mux option, etc.) are not applicable. (Step 11) The home AAA server
responds with the RADIUS Accounting-Response (Start). (Step 12)
Bearer traffic traverses through the IIF in both directions. For
routing MS-originated packets, the IIF routes packets received from
the MS's GTP tunnel (identified by a TEID) to the MS's L2TP
tunnel/session. For routing MS-terminated packets, the IIF routes
packets received from the MS's L2TP tunnel/session to the MS's GTP
tunnel. IPsec can be used to protect the L2TP tunnel/session
between LNS and IIF, and the GTP tunnels between IIF and SGSN.
(Step 13)
[0056] CDMA2000 Packet Data Foreign Mode with Mobile IPv4
[0057] FIG. 4A is an exemplary block diagram of a CDMA2000 packet
data foreign mode with Mobile IPv4. This section describes the
roaming scenario where a GPRS native subscriber operates Mobile
IPv4 [IS-835-C] in the CDMA2000 packet data foreign mode. FIG. 4A
also depicts the functions and control interface provided by the
IIF in this case. In this embodiment, the home system 10 can be a
GPRS system. A GPRS native subscriber roams to a CDMA 2000 packet
data system and uses Simple IP. The home system 10 comprises a GSM
home location register 124, a GGSN 126, and an AAA entity 128. The
visited system 20 can be a CDMA 2000 packet data system that
comprises a ANSI-41 visited location register 111, an AAA entity
116, and a packet data serving node/foreign agent 118.
[0058] The interface 30 or "IIF" comprises an ANSI-41 home location
register 131 coupled to the ANSI-41 visited location register 111
via a D interface 113, a GSM visited location register 133 coupled
to the GSM home location register 124 via a D interface 121, a SGSN
137 coupled to the GGSN 126 via a Gp interface 127, an AAA entity
140 coupled to the AAA entity 128 via a X4 interface 129 and
coupled to the AAA entity 116 via a X3 interface 117, and a home
agent 135 coupled to the packet data serving node/foreign agent 118
via a X1 interface 115. The IIF provides both GSM VLR and ANSI-41
HLR emulation to allow the subscriber to register. This
interworking can be provided over the interface reference "D". The
IIF provides HA and SGSN emulation to support bearer connectivity
between the visited and home networks via the IIF. This
interworking can be provided over the interface reference "X1" and
"Gn". The IIF provides AAA emulation to interact with the visited
network's AAA for Mobile IP authentication and 3GPP2 packet data
accounting. The IIF also may interact with the home network's AAA
for 3GPP packet data accounting. This interworking can be provided
over the interface reference "X3" and "X4". The IIF/AAA
requirements for CDMA2000 packet data foreign mode with mobile IP
will be described below in greater detail.
[0059] If bearer connectivity between the visited CDMA2000 packet
data system and home GPRS system is not required, the Gp interface
is not required. In this case, mobile-originated data traffic can
be routed directly to the Internet via the PDSN/FA in the visited
system, or via the IIF/HA if reverse tunneling is enabled.
Mobile-terminated data traffic is routed to the PDSN/FA via the
IIF/HA. The interface X3 and X4 are required for the IIF to
interwork AAA messages between the CDMA2000 AAA server and GPRS AAA
server.
[0060] Thus, for a user homed in a GSM system roaming to a CDMA
Mobile IP system, the IIF may present a HA interface to the CDMA
system and a SGSN interface to the GSM system. A subset of SGSN
functions is required including APN resolution. The IIF may serve
as the endpoint for the Mobile IP and GTP tunnels, with a packet
routing function between the HA and SGSN functions.
[0061] FIG. 4B is an exemplary call flow diagram that shows Mobile
IPv4 operation in the CDMA2000 packet data foreign mode. This call
flow example shows a roaming scenario where a GPRS native
subscriber operates Mobile IPv4 [IS-835-C] in the CDMA2000 packet
data foreign mode. In this example, the home GPRS system doesn't
support HA; thus, the MS has shared secrets with the IIF for Mobile
IP authentication. The home GPRS system dynamically assigns an IP
address to the MS. All MS's data traffic (MS-originated and
MS-terminated) traverses through the IIF and home GPRS system. The
IIF receives 3GPP2 accounting records from the visited CDMA2000
system and may map them to 3GPP accounting records and forward them
to the home GPRS system via RADIUS.
[0062] The MS originates SO 33 and establishes a PPP session with
the PDSN/FA. (Step 1) The PDSN/FA sends one or more Mobile IP Agent
Advertisements to the MS, because the omission of the IP-Address
Configuration Option during the PPP IPCP negotiation indicates that
the MS wishes to use Mobile IP. The Agent Advertisement contains
the FA Care-of Address and the FA Challenge (FAC). (Step 2)
[0063] The MS sends the Mobile IP Registration Request to the
PDSN/FA. The following information can be contained in the
Registration Request: MS's NAI [RFC 2794] has the format of
<username>@<domain_name>, where the domain_name
identifies the MS's home GPRS system. MS-HA authenticator can be
computed based on the content of the Registration Request and the
secret shared between the MS and HA [RFC 2002]. MS-AAA
authenticator can be computed based on the FAC and the secret
shared between the MS and home AAA server [RFC 3012]. The HA
Address field can be set to a known value if the MS uses a
permanent HA, or to 0.0.0.0 if the MS wants a new HA assigned by
the home network. The HA field can be set to 0.0.0.0 to request a
new address assigned by the HA. The T-bit can be set to one to
request the PDSN/FA to establish a reverse tunnel to the MS's HA.
(Step 3)
[0064] The PDSN/FA generates a RADIUS Access-Request conveying MS's
NAI, FAC authenticator, FAC, HA address, etc. [IS-835]. Because the
domain name of the MS's NAI indicates a GPRS system, the PDSN/FA
sends a RADIUS Access-Request to the IIF via the AAA in the
CDMA2000 system. The IIF may modify the message in accordance with
[3GPP TS 29.061]. (Step 4) If the authentication is successful, the
home AAA server responds with the RADIUS Access-Accept. The message
is routed back to the PDSN via IIF and visited AAA. The IIF may
modify the message in accordance with [P.S0001-A V3.0]. (Step 5)
The PDSN/FA forwards the Mobile IP Registration Request to the HA
function in the IIF. The IIF verifies the MS-HA authenticator in
the Mobile IP Registration Request. (Step 6)
[0065] If the authentication is successful, the IIF SGSN
functionality establishes GTP tunnels with a GGSN in the home GPRS
system and can request an IP address from the GGSN. The IIF SGSN
functionality derives an APN that has the format <Network
ID>.mnc<MNC>.mcc<MCC>.gprs [TS 23.003]. The
<Network ID> is the realm portion of the MS's NAI and
indicates which GGSN the MS wants to access for the requested
service. The <MNC> and <MCC> are derived from the MS's
IMSI. The MS's NAI and IMSI are available from the RADIUS
Access-Request in step 4. The SGSN functionality uses the derived
APN as the lookup name to query GPRS DNS server (not shown in the
figure) and from it obtains a list of available GGSNs that can be
used to support the requested service. The IIF SGSN functionality
sends the Create PDP Context Request to the selected GGSN. The
Requested PDP Address in the message is set to 0.0.0.0 to request a
new IP address. (Step 7) The GGSN responds with the Create PDP
Context Response including the new IP address assigned to the MS.
(Step 8) The IIF acts as the HA and sends the Mobile IP
Registration Reply to the MS via the PDSN/FA. The Home Address
field in the Mobile IP Registration Reply can be set to the IP
address assigned by the GGSN. (Step 9) The PDSN sends the RADIUS
Accounting-Request (Start) containing 3GPP2 packet data accounting
information [P.S0001-A V3.0]. Because the domain name of the MS's
NAI indicates a GPRS system, the RADIUS Accounting-Request (Start)
is routed to the home AAA in the GPRS system via the visited AAA
and IIF. The IIF may modify the message in accordance with [3GPP TS
29.061]. (Step 10) The IIF acts as the RADIUS server and replies
with the RADIUS Accounting-Response (Start). (Step 11)
[0066] Bearer traffic traverses through the IIF in both directions.
For routing MS-originated packets, the IIF routes packets received
from the Mobile IP reverse tunnel to the MS's GTP tunnel
(identified by a TEID). For routing MS-terminated packets, the IIF
routes packets received from the GTP tunnel to a HA-to-FA tunnel.
IPsec can be used to protect the Mobile IP tunnels between PDSN/FA
and IIF, and the GTP tunnels between IIF and GGSN. (Step 12)
[0067] IIF/AAA Requirements for CDMA2000 Packet Data Foreign Mode
with Mobile IP
[0068] The IIF requirements to process the RADIUS Access-Request
received from the visited CDMA2000 packet data system will now be
described.
[0069] The IIF proxies all IETF RADIUS attributes without
modification, except the Calling-Station-ID attribute,
Called-Station-ID attribute, and Framed-Protocol attribute. The
processing of these three attributes is described below. If the
Calling-Station-ID attribute in the received RADIUS Access-Request
contains IMSI, the IIF copies the IMSI into the 3GPP-IMSI attribute
[3GPP TS 29.061] and include it in the RADIUS Access-Request
destined for the MS's home GPRS system. The IIF does not include
the Calling-Station-ID attribute in the RADIUS Access-Request sent
to the home AAA in the GPRS system. If the Calling-Station-ID
attribute in the received RADIUS Access-Request contains MIN or
IRM, the IIF maps it to the MS's IMSI used in the home GPRS system
and include it in the 3GPP-IMSI attribute of the RADIUS
Access-Request destined for the home GPRS system. The IIF does not
include the Calling-Station-ID attribute in the RADIUS
Access-Request sent to the home AAA in the GPRS system.
[0070] The IIF includes the Called-Station-ID attribute in the
RADIUS Access-Request destined for the MS's home GPRS system. The
Value field of the Called-Station-ID attribute is set to the APN
(see section 8.3.4). If the Framed-Protocol attribute is included
in the received RADIUS Access-Request, the IIF overrides the value
to 7 [3GPP TS 29.061]. The IIF removes all 3GPP2 VSAs from the
received RADIUS Access-Request. The IIF is not required to include
any 3GPP VSAs, except the 3GPP-IMSI attribute, in the transmitted
RADIUS Access-Request destined for the MS's home GPRS system.
[0071] The IIF requirements to process the RADIUS Access-Accept
received from the MS's home GPRS system will now be described.
[0072] The IIF proxies all IETF RADIUS attributes without
modification. The IIF removes all 3GPP VSAs from the received
RADIUS Access-Accept, before transmitting the RADIUS Access-Accept
to the visited CDMA2000 packet data system.
[0073] If the policy of the home GPRS system requires the roaming
MS's data traffic to traverse through the home GPRS system via the
IIF, and the HA-Address VSA was included in the corresponding
RADIUS Access-Request received earlier from the visited CDMA2000
packet data system, the IIF includes the
Reverse-Tunnel-Specification VSA in the transmitted RADIUS
Access-Accept destined for the visited CDMA2000 packet data system.
The value field of the VSA is set to 1 indicating that reverse
tunneling is required.
[0074] The IIF requirements to process the RADIUS
Accounting-Request START and Accounting-Request INTERIM are the
same as the requirements to process the RADIUS Access-Request.
[0075] The IIF requirements to process the RADIUS
Accounting-Request STOP are the same as the requirements to process
the RADIUS Access-Request with the following additional
requirements: If the Session-Continue VSA is set to FALSE in the
received RADIUS Accounting-Request STOP, and if the IIF has not
previously received an Accounting-Request (Start) from another PDSN
with the same IP Address (for the case of inter-PDSN handoff with
Mobile IP), the IIF inserts the 3GPP-Session-Stop-Indicator VSA to
indicate that the PDP session has been terminated.
[0076] CDMA2000 Packet Data Foreign Mode with Simple IP
[0077] FIG. 5A is an exemplary block diagram of a CDMA2000 packet
data foreign mode with Simple IP. This section describes the
roaming scenario where a GPRS native subscriber operates IPv4 or
IPv6 in the CDMA2000 packet data foreign mode. FIG. 5A also depicts
the functions and control interface provided by the interface 30 or
"IIF" in this case. In this embodiment, the home system 10 can be a
GPRS system wherein a GPRS native subscriber roams to a CDMA 2000
packet data system and uses Mobile IPv4. The home system 10
comprises a GSM home location register 124, a GGSN 126, and an AAA
entity 128. The visited system 20 can be a CDMA 2000 packet data
system that comprises a ANSI-41 visited location register 111, an
AAA entity 116, and a home system 109.
[0078] The interface 30 or "IIF" comprises an ANSI-41 home location
register 131 coupled to the ANSI-41 visited location register 111
via a D interface 113, a GSM visited location register 133 coupled
to the GSM home location register 124 via a D interface 121, a SGSN
137 coupled to the GGSN 126 via a Gp interface 127, an AAA entity
140 coupled to the AAA entity 128 via a X4 interface 129 and
coupled to the AAA entity 116 via a X3 interface 117, and a LCS
entity 139 coupled to the packet data serving node/LAC entity 109
via an X2 interface 119. The IIF provides both GSM VLR and ANSI-41
HLR emulation to allow the subscriber to register. This
interworking can be provided over the interface reference "D". The
IIF provides LNS and SGSN emulation to support bearer connectivity
between the visited and home networks via the IIF. This
interworking can be provided over the interface reference "X2" and
"Gn". The IIF provides AAA emulation to interact with the visited
network's AAA for L2TP authentication and 3GPP2 packet data
accounting. The IIF also may interact with the home network's AAA
for 3GPP packet data accounting. This interworking can be provided
over the interface reference "X3" and "X4". The IIF/AAA
requirements for CDMA2000 packet data foreign mode with Simple IP
will be described below in greater detail.
[0079] If bearer connectivity between the visited CDMA2000 packet
data system and home GPRS system is not required, the X2 and Gp
interface are not required. In this case, both mobile-originated
and mobile-terminated data traffic is routed to/from the Internet
via the PDSN in the visited system. The interface X3 and X4 are
required for the IIF to interwork AAA messages between the CDMA2000
AAA server and GPRS AAA server.
[0080] Thus, for a user homed in a GSM system roaming to a CDMA
Simple IP system, the IIF may present a L2TP Network Server (LNS)
interface to the CDMA system and a SGSN interface to the GSM
system. A subset of SGSN functions is required including APN
resolution. The IIF may serve as the endpoint for the Mobile L2TP
and GTP tunnels, with a packet routing function between the LNS and
SGSN functions.
[0081] FIG. 5B is an exemplary call flow diagram that shows Simple
IP operation in the CDMA2000 packet data foreign mode. This call
flow example illustrates a roaming scenario where a GPRS native
subscriber operates Simple IP in the CDMA2000 packet data foreign
mode. In this example, the MS has shared secrets with the home AAA
in the GPRS system for CHAP authentication. The home GPRS system
dynamically assigns an IP address to the MS. All MS's data traffic
(MS-originated and mobile-terminated) traverses through the IIF and
home GPRS system. The IIF receives 3GPP2 accounting records from
the visited CDMA2000 system and maps it to 3GPP accounting records
and forward it to the home GPRS system via RADIUS.
[0082] The MS originates SO 33 and initiates PPP LCP negotiation
with the PDSN/LAC. CHAP can be negotiated as the protocol for PPP
authentication. (Step 1) PDSN/LAC sends a CHAP challenge to the MS.
(Step 2) The MS replies with its NAI and a challenge response
computed based on the challenge and the secret shared with the home
AAA in the GPRS system. The PDSN/LAC sends RADIUS Access-Request.
Because the domain name of the MS's NAI indicates a GPRS system,
the RADIUS Access-Request can be routed through the visited AAA and
IIF that proxies the message to the home AAA in the GPRS system.
The IIF may modify the message in accordance with [3GPP TS 29.061].
(Step 3) If the authentication is successful, the home AAA responds
with the RADIUS Access-Accept. The message can be routed back to
the PDSN/LAC via the IIF and visited AAA. The IIF inserts the
Tunnel-Server-Endpoint attribute in the RADIUS Access-Accept. This
attribute informs the PDSN/LAC to establish a L2TP tunnel with the
IIF that acts as the LNS. The PDSN/LAC sends the CHAP Success to
inform the MS about the successful authentication. (Step 4)
[0083] The PDSN/LAC establishes a L2TP tunnel/session with the IIF
that acts as the LNS. During the L2TP tunnel/session establishment,
the PDSN/LAC forwards the LCP information (exchanged between the MS
and PDSN/LAC) to the IIF. The IIF LNS functionality may initiate
CHAP challenge (not shown in the figure) to authenticate the MS
before IPCP negotiation. (Step 5) The IIF SGSN functionality
establishes GTP tunnels with a GGSN in the home GPRS system and can
request an IP address from the GGSN. The IIF derives an APN that
has the format <Network
ID>.mnc<MNC>.mcc<MCC>.gprs. The <Network ID>
is the realm portion of the MS's NAI and is used to indicate which
GGSN the MS wants to access for the requested service. The
<MNC> and <MCC> are derived from the MS's IMSI. The
MS's NAI and IMSI are available from the RADIUS Access-Request in
step 3. The IIF SGSN functionality uses the derived APN as the
lookup name to query GPRS DNS server (not shown in the figure) and
obtains a list of available GGSNs that can be used to support the
requested service. The IIF SGSN functionality sends the Create PDP
Context Request to the selected GGSN. The Requested PDP Address in
the message is set to 0.0.0.0 to request a new IP address. (Step 6)
The GGSN responds with the Create PDP Context Response including
the new IP address assigned to the MS. (Step 7)
[0084] This new IP address can be assigned to the MS during the PPP
IPCP negotiation between the IIF and MS. (Step 8) The PDSN/FA sends
the RADIUS Accounting-Request (Start) containing 3GPP2 packet data
accounting information [IS-835]. The PDSN sends the RADIUS
Accounting-Request (Start) containing 3GPP2 packet data accounting
information [P.S0001-A V3.0]. Because the domain name of the MS's
NAI indicates a GPRS system, the RADIUS Accounting-Request (Start)
is routed to the home AAA in the GPRS system via the visited AAA
and IIF. The IIF may modify the message in accordance with [3GPP TS
29.061]. (Step 9) The home AAA replies with the RADIUS
Accounting-Response (Start) that is routed back to the PDSN via IIF
and visited AAA. (Step 10)
[0085] Bearer traffic traverses through the IIF in both directions.
For routing MS-originated packets, the IIF routes packets received
from the MS's L2TP tunnel/session to the MS's GTP tunnel
(identified by a TEID). For routing MS-terminated packets, the IIF
routes packets received from the MS's GTP tunnel to the MS's L2TP
tunnel/session. IPsec can be used to protect the L2TP
tunnel/session between PDSN/LAC and IIF, and the GTP tunnels
between IIF and GGSN. (Step 11)
[0086] IIF/AAA Requirements for CDMA2000 Packet Data Foreign Mode
with Simple IP
[0087] The IIF requirements to process the RADIUS Access-Request
are the same as the requirements to process the RADIUS
Access-Request for the CDMA2000 Packet Data Foreign Mode with
Mobile IP, described above.
[0088] The IIF requirements to process the RADIUS Access-Accept are
similar to the requirements for processing the RADIUS Access-Accept
for the CDMA2000 Packet Data Foreign Mode with Mobile IP, however,
if the policy of the home GPRS system requires the roaming MS's
data traffic to traverse through the home GPRS system via the IIF,
and the HA-Address VSA was not included in the corresponding RADIUS
Access-Request received earlier from the visited CDMA2000 packet
data system, the IIF inserts the Tunnel-Server-Endpoint,
Tunnel-Type, and Tunnel-Medium-Type attributes in the transmitted
RADIUS Access-Accept destined for the visited CDMA2000 packet data
system. The Tunnel-Server-Endpoint attribute indicates the IIF/LNS
address. The Tunnel-Type attribute indicates L2TP. The
Tunnel-Medium-Type attribute indicate IPv4.
[0089] The IIF requirements to process the RADIUS
Accounting-Request START and Accounting-Request INTERIM are the
same as the requirements to process the RADIUS Accounting-Request
START and Accounting-Request INTERIM for the CDMA2000 Packet Data
Foreign Mode with Mobile IP, described above.
[0090] The IIF requirements to process the RADIUS
Accounting-Request STOP are the substantially the same as the
requirements to process the RADIUS Accounting-Request STOP for the
CDMA2000 Packet Data Foreign Mode with Mobile IP, however, if the
Session-Continue VSA is set to FALSE in the received RADIUS
Accounting-Request STOP, and the IP-Technology VSA indicates Simple
IP, the IIF inserts the 3GPP-Session-Stop-Indicator VSA to indicate
that the PDP session has been terminated.
[0091] Those of skill in the art would understand that information
and signals may be represented using any of a variety of different
technologies and techniques. For example, data, instructions,
commands, information, signals, bits, symbols, and chips that may
be referenced throughout the above description may be represented
by voltages, currents, electromagnetic waves, magnetic fields or
particles, optical fields or particles, or any combination
thereof.
[0092] Those of skill would further appreciate that the various
illustrative logical blocks, modules, circuits, and algorithm steps
described in connection with the embodiments disclosed herein may
be implemented as electronic hardware, computer software, or
combinations of both. To clearly illustrate this interchangeability
of hardware and software, various illustrative components, blocks,
modules, circuits, and steps have been described above generally in
terms of their functionality. Whether such functionality can be
implemented as hardware or software depends upon the particular
application and design constraints imposed on the overall system.
Skilled artisans may implement the described functionality in
varying ways for each particular application, but such
implementation decisions should not be interpreted as causing a
departure from the scope of the present invention.
[0093] The various illustrative logical blocks, modules, and
circuits described in connection with the embodiments disclosed
herein may be implemented or performed with a general purpose
processor, a digital signal processor (DSP), an application
specific integrated circuit (ASIC), a field programmable gate array
(FPGA) or other programmable logic device, discrete gate or
transistor logic, discrete hardware components, or any combination
thereof designed to perform the functions described herein. A
general purpose processor may be a microprocessor, but in the
alternative, the processor may be any conventional processor,
controller, microcontroller, or state machine. A processor may also
be implemented as a combination of computing devices, e.g., a
combination of a DSP and a microprocessor, a plurality of
microprocessors, one or more microprocessors in conjunction with a
DSP core, or any other such configuration.
[0094] The steps of a method or algorithm described in connection
with the embodiments disclosed herein may be embodied directly in
hardware, in a software module executed by a processor, or in a
combination of the two. A software module may reside in RAM memory,
flash memory, ROM memory, EPROM memory, EEPROM memory, registers,
hard disk, a removable disk, a CD-ROM, or any other form of storage
medium known in the art. An exemplary storage medium can be coupled
to the processor such the processor can read information from, and
write information to, the storage medium. In the alternative, the
storage medium may be integral to the processor. The processor and
the storage medium may reside in an ASIC. The ASIC may reside in a
user terminal. In the alternative, the processor and the storage
medium may reside as discrete components in a user terminal.
[0095] The previous description of the disclosed embodiments can be
provided to enable any person skilled in the art to make or use the
present invention. Various modifications to these embodiments will
be readily apparent to those skilled in the art, and the generic
principles defined herein may be applied to other embodiments
without departing from the spirit or scope of the invention. Thus,
the present invention can be not intended to be limited to the
embodiments shown herein but can be to be accorded the widest scope
consistent with the principles and novel features disclosed
herein.
* * * * *