WO2001091419A1 - Method for address resolution to find call control function instances - Google Patents

Method for address resolution to find call control function instances Download PDF

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Publication number
WO2001091419A1
WO2001091419A1 PCT/EP2001/005682 EP0105682W WO0191419A1 WO 2001091419 A1 WO2001091419 A1 WO 2001091419A1 EP 0105682 W EP0105682 W EP 0105682W WO 0191419 A1 WO0191419 A1 WO 0191419A1
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WO
WIPO (PCT)
Prior art keywords
cscf
control function
state control
call state
address
Prior art date
Application number
PCT/EP2001/005682
Other languages
French (fr)
Inventor
Adam Boeszoermenyi
Otto Janko
Mohammad Ali Memar
Original Assignee
Siemens Aktiengesellschaft
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens Aktiengesellschaft filed Critical Siemens Aktiengesellschaft
Publication of WO2001091419A1 publication Critical patent/WO2001091419A1/en

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W8/00—Network data management
    • H04W8/26—Network addressing or numbering for mobility support
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L61/00—Network arrangements, protocols or services for addressing or naming
    • H04L61/45—Network directories; Name-to-address mapping
    • H04L61/4505—Network directories; Name-to-address mapping using standardised directories; using standardised directory access protocols
    • H04L61/4511—Network directories; Name-to-address mapping using standardised directories; using standardised directory access protocols using domain name system [DNS]

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Databases & Information Systems (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

A mobile station can be provided with necessary information of call state control functions, especially in case of roaming without expenditure when using a proxy call state control function (P-CSCF) acting as a border element and controlling local services and occasionally necessary resources within this network. According to a preferred embodiment the selected call state control function (CSCF) acts as a redirect server and redirects a session initiation protocol (SIP) request to another, especially an (CSCF).

Description

Description:
Method for* address resolution to find call control runction instances
Present invention relates to an address resolution procedure to find various CSCF instances in an IP controlled network according to pre-characterising part of claim 1.-
For Universal Mobile Telecommunication System (UMTS) there is known a routing model introduced in Third Generation Partnership Project (3GPP) Standard *TS 23.228". In each network exists a Proxy Call State Control Function (P-CSCF) which is the first contact point within the IM CN (IP Multimedia Core Network) subsystem.
When a mobile station or mobile host visits a foreign network then IP-Address (IP: Internet-Protocol), Standard-Gateway and Domain Name Server (DNS) are assigned at bearer level. Their values are taken from the address space of the visited network and assigned during Packet Data Protocol (PDP) context activation using Dynamic Host Configuration Protocol (DHCP) , for example. All IP addresses are globally visible i.e. IP addresses are not taken from a private address space.
The object of the invention is to provide a mobile station with necessary information of call state control functions, in both cases, located at home and while roaming.
This object is solved by a method comprising features of claim 1 and a system comprising features of claim 7. Preferred embodiments are subject of depending claims. According to a preferred embodiment the address resolution is based on domain name server information exclusively, therefore no other protocols or instances have to be introduced.
All Call State Control Function (CSCF) instances can be found, using similar procedures. The solution requires no changes in the underlying 2nd Generation Access network, especially GSM/UMTS/GPRS network.
The Cx interface connecting Home Subscriber Server (HSS) and home call state control function must not be used across network boundaries. Preferably, the home call state control' function is the contact point within an operator' s network for all connections destined to a subscriber of that network operator, or a roaming subscriber currently located within that network operator's service area.
There is not required a fixed assignment between mobile station or mobile host as visiting station and H-CSCF, although a fixed assignment would be possible and would speed up address resolution.
There exist flexibility in CSCF selection by using Session Initiation Protocol (SIP) redirects conducted either by the selected CSCF or optionally a dedicated redirect server e.g. load sharing.
A preferred embodiment is described in the following refer- ring to enclosed drawing. Fig. 1 discloses a communication system providing full home control and a proxy CSCF in the visited network first showing a plurality of devices known as such.
Fig. 2 shows a flow chart regarding attach, registration and address resolution procedures in such a visited network.
In present embodiment the local domain name server DNS of the Visited Network is used to find the call state control function CSCF responsible for the call control, i.e. the proxy" CSCF (P-CSCF) . As can be gathered from Fig. 2 the mobile station (MS) asks the domain name server DNS for a P-CSCF address in one of the first steps, when asking for a call state control function CSCF service. The domain name server DNS returns the addresses of possible proxy call state control function P-CSCF instance. The mobile station MS sends an information like „sip:registerXN to this proxy call state control function P-CSCF.
There are at least four cases where the home call state control function H-CSCF discovery is executed to find the home call state control function H-CSCF of an mobile station MS as follows .
If the mobile station MS is attached in the home network, the (proxy) call state function P-CSCF assigned to mobile station MS during PDP Context activation Procedure (PDP: Packet Data Protocol) has to find out it's own home call state control function H-CSCF.
If the mobile station MS is roaming in a visited 3rd Generation network like UMTS, the proxy call state control function P-CSCF assigned to mobile station MS during PDP Context acti- vation Procedure has to find out the home call state control function H-CSCF of the calling mobile station MS.
If the mobile station MS is roaming in a visited 3rd Genera- tion network like UMTS, the proxy call state control function P-CSCF assigned to* mobile station MS during PDP Context activation Procedure has to find out it's own home call state control function H-CSCF.
During call control (e.g. sip: invite" ) , the home call state control function H-CSCF of the calling party has to find out the address of the device providing home call state control function H-CSCF of the called party.
To build up a connection with an ordered service at first the MSISDN of the mobile station MS is translated to a domain name e.g. λX subscriber .hlr .network. country. cscf" . Thereafter the domain name server DNS is queried and returns the corresponding IP address if found or an error if not found. The letter "x" of ..."xcscf" has different value for different roles of CSCF's.
If the first domain name server query was not successful, domain name server DNS is queried again using Λλhlr.network, country,xcscf", i.e. without subscriber data.
If the second domain name server query was not successful, domain name server DNS is queried again using '"network, country.xcscf" , i.e. without subscriber and home loca- tion register data. This query must be successful. Otherwise no services can be provided in the home network. After the IP address is found session initiation protocol (SIP) messages are forwarded to the returned IP address (e.g. 'sip:register" or * sip: invite") . In the case that no address could be found, the DNS generates an error message.
According to a special embodiment any call state control function CSCF which is selected with domain name server queries can redirect a session initiation protocol (SIP) request to another call state control function CSCF if necessary, for example for load balancing or to optimise the signalling path or whatever. Even more sophisticated, domain name server DNS can return the address of a dedicated session initiation protocol (SIP) redirect server. The proxy call state control server P-CSCF can act as SIP redirect server. This optional new network entity does not process session initiation protocol messages by itself, but redirects them to an appropriate call state control function CSCF. The redirect server makes its decision based on information private to the operator.
If there is a fixed assignment between the mobile station MS and the home call state control function H-CSCF known by the mobile station MS, e.g. the address of the home call state control function H-CSCF can be stored in a SIM card of the mobile station MS, then the discovery of the home call state control function H-CSCF of the calling party as described above can be dropped.
If the mobile station MS is roaming, it can hand over the address of it's own home call state control function H-CSCF to the proxy call state control function P-CSCF, e.g. in the * sip: register request" via a "route" parameter. IP addresses can be taken from a public or local address space. When using a local address space additionally network address translation can be necessary.
Proxy, or home call state control functions acts as call control instances in general which can be found via the domain name server or another device returning their addresses.

Claims

Patent claims :
1. Method for address resolution to find call state control function instances in an internet protocol (IP) based network c h a r a c t e r i s e d in that a queried domain name server (DNS) returns an IP address corresponding to a requested call control instance address .
2. Method according to claim 1, wherein the call control instance acts as call state control function (CSCF) .
3. Method according to claim 2, wherein the call state control function (P-CSCF) acts as a border * element and controls local services and occasionally necessary resources within a contacted network.
4. Method according to claim 2 or 3, wherein the selected call state control function (CSCF) acts as a redirect server and redirects a session initiation protocol request to another call state control function (CSCF) .
5. Method according to any preceding claim, wherein the call control instance acts as first contact point within a core network subsystem.
6. Method according to any preceding claim, wherein an identification number (MSISDN) of a calling station (MS) is translated to a domain name.
7. System for executing a method according to any preceding claim, said system being a wireless telecommunications network, especially an UMTS, or a wireless local area data network, especially a HiperLAN, having a domain name server (DNS) and a> call control instance, said domain name server (DNS) returning an IP address to a requested call control instance address after an corresponding query of a connecting station (MS) ..
PCT/EP2001/005682 2000-05-22 2001-05-17 Method for address resolution to find call control function instances WO2001091419A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP00110837.2 2000-05-22
EP00110837 2000-05-22

Publications (1)

Publication Number Publication Date
WO2001091419A1 true WO2001091419A1 (en) 2001-11-29

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002054686A2 (en) * 2001-01-05 2002-07-11 Nokia Corporation Routing of call made to subscriber
WO2003105436A1 (en) * 2002-06-07 2003-12-18 Siemens Aktiengesellschaft Method and device for authenticating a subscriber for utilizing services in a wireless lan (wlan)
WO2004077789A1 (en) * 2003-02-25 2004-09-10 Nokia Corporation Routing optimization in a sip call establishment
WO2004089022A1 (en) * 2003-04-04 2004-10-14 Nokia Corporation Multiple registration of a subscriber in a mobile communication system
KR100518433B1 (en) * 2002-10-28 2005-09-29 엘지전자 주식회사 System and Method for Processing Hand-over
WO2008086744A1 (en) * 2007-01-12 2008-07-24 Huawei Technologies Co., Ltd. Method of implementing call establishment, system and call controlling network element thereof
EP2082329A2 (en) * 2006-11-15 2009-07-29 Starent Networks Corporation System and method for redirecting requests

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0881812A2 (en) * 1997-05-26 1998-12-02 Oki Electric Industry Co., Ltd. Telephone communication method capable of relating a telephone terminal and a speech channel IP address at the time of call connection
WO1999011042A1 (en) * 1997-08-23 1999-03-04 Koninklijke Philips Electronics N.V. Wireless network
WO1999038303A1 (en) * 1998-01-22 1999-07-29 Nortel Networks Corporation Proxy server for tcp/ip network address portability

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0881812A2 (en) * 1997-05-26 1998-12-02 Oki Electric Industry Co., Ltd. Telephone communication method capable of relating a telephone terminal and a speech channel IP address at the time of call connection
WO1999011042A1 (en) * 1997-08-23 1999-03-04 Koninklijke Philips Electronics N.V. Wireless network
WO1999038303A1 (en) * 1998-01-22 1999-07-29 Nortel Networks Corporation Proxy server for tcp/ip network address portability

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
ANQUETIL L -P ET AL: "MEDIA GATEWAY CONTROL PROTOCOL AND VOICE OVER IP GATEWAYS. MGCP AND VOIP GATEWAYS WILL OFFER SEAMLESS INTERWORKING OF NEW VOIP NETWORKS WITH TODAY'S TELEPHONE NETWORKS", ELECTRICAL COMMUNICATION,ALCATEL. BRUSSELS,BE, 1 April 1999 (1999-04-01), pages 151 - 157, XP000830045, ISSN: 0013-4252 *
NAPOLITANO-RICAGNI: "UMTS all-IP Mobility Management, Call and session control Procedure", INTERNET-DRAFT, XP002149519, Retrieved from the Internet <URL:http://195.103.28.224/ricagni/draft-ricagni-megaco-umts-all-ip-00.pdf> [retrieved on 20001002] *

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002054686A2 (en) * 2001-01-05 2002-07-11 Nokia Corporation Routing of call made to subscriber
WO2002054686A3 (en) * 2001-01-05 2002-08-01 Nokia Corp Routing of call made to subscriber
US7043246B2 (en) 2001-01-05 2006-05-09 Nokia Corporation Routing of call made to subscriber
WO2003105436A1 (en) * 2002-06-07 2003-12-18 Siemens Aktiengesellschaft Method and device for authenticating a subscriber for utilizing services in a wireless lan (wlan)
US7634249B2 (en) 2002-06-07 2009-12-15 Siemens Aktiengesellschaft Method and device for authenticating a subscriber for utilizing services in a wireless LAN while using an IP multimedia subsystem of a mobile radio network
KR100518433B1 (en) * 2002-10-28 2005-09-29 엘지전자 주식회사 System and Method for Processing Hand-over
WO2004077789A1 (en) * 2003-02-25 2004-09-10 Nokia Corporation Routing optimization in a sip call establishment
US7542481B2 (en) 2003-02-25 2009-06-02 Nokia Corporation Connection optimization for communications in multiple access environment
WO2004089022A1 (en) * 2003-04-04 2004-10-14 Nokia Corporation Multiple registration of a subscriber in a mobile communication system
EP2082329A2 (en) * 2006-11-15 2009-07-29 Starent Networks Corporation System and method for redirecting requests
EP2082329A4 (en) * 2006-11-15 2013-11-27 Cisco Tech Inc System and method for redirecting requests
WO2008086744A1 (en) * 2007-01-12 2008-07-24 Huawei Technologies Co., Ltd. Method of implementing call establishment, system and call controlling network element thereof

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