Method, switching means and telecommunication systems for performing data communications between subscriber stations

• US 6,577,637 B1
• Filed: 12/16/1998
• Issued: 06/10/2003
• Est. Priority Date: 12/17/1997
• Status: Expired due to Term

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Sieppi, Jukka
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): Pezzlo, John
• Application Number:
  US09/212,426
• Time in Patent Office: 1,637 Days
• Field of Search: 370/352-356, 370/277, 370/401, 370/477, 370/252, 704/270, 704/19, 379/58.17
• US Class Current: 370/401
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04W 88/181 Transcoding devices; Rate adaptation devices

Abstract

A switching means (BSC/MSC/VLR) of a mobile radio communication network (PLMN) contains a subscriber type determining means (SSTDM) which determines on the basis of call set-up messages whether in particular the second subscriber station (WS) of an IP-network (INTRANET) is capable of performing an audio data encoding/decoding, in particular a GSM speech encoding/decoding. The subscriber station type determining means (SSTDM) switches off an audio data encoding/decoding means (CODEC) in a base station controller (BSC) if the second subscriber station (WS) is capable of performing the speech encoding/decoding. Thus, a deterioration of the speech quality due to performing unnecessary audio data encoding/decoding is avoided and the bandwidth in the PLMN/data network can be utilized more efficiently.

Claims

1. A method for performing data communications between a first subscriber station of a mobile radio communication network and a second subscriber station connectable to the mobile radio communication network, wherein at least the first subscriber station includes an audio data encoding/decoding means, comprising the following steps:

a) sending a call set-up message from the first or second subscriber station to a switching means of the mobile radio communication network to set up a call between the first and second subscriber stations;

b) determining on the basis of said call set-up message whether the second subscriber station is of a type also including an audio data encoding/decoding means, said determining step including;

b1) accessing, by the switching means, an internal memory containing calling numbers, associated Internet Protocol (IP) addresses, and IP user names for subscriber stations in the network; and

b2) comparing a calling number for the second subscriber station with the calling numbers, IP-addresses, and IP user names stored in the memory to determine whether the second subscriber station is of a type also including an audio data encoding/decoding means;

c) setting up a call between the first and second subscriber station;

d) switching off an audio data encoding/decoding means in said switching means, if the second subscriber station also includes an audio data encoding/decoding means; and

e) encoding/decoding audio data at the first and second subscriber station using the respective encoding/decoding means and communicating said coded audio data through said switching means without applying an audio data coding/decoding thereto in said switching means.

2. The method according to claim 1, wherein the mobile radio communication network is compatible with the Global System for Mobile Communications (GSM), and the audio data is GSM-coded speech data.

3. A switch in a mobile radio communication network for communicating data between a first subscriber station of the mobile radio communication network and a second subscriber station connectable to the mobile radio communication network, wherein at least the first subscriber station includes a first audio data encoder/decoder, said switch comprising:

a) a second audio data encoder/decoder having a first operable state in which digital audio data received from the first/second subscriber station is encoded/decoded, and a second operable state in which digital audio data received from the first/second subscriber station is passed through the switch without encoding/decoding;

b) means for determining whether the second subscriber station is of a type having an audio data encoder/decoder, said determining means comprising;

b1) an internal memory for storing calling numbers, associated IP-addresses, and IP-user names for subscriber stations; and

b2) means for comparing entries in the memory with a calling number of the second subscriber station to determine whether the second subscriber station is a station having an audio data encoder/decoder, said calling number of the second subscriber station being included in a call set-up message sent from the first or second subscriber station; and

c) a controller that switches the second audio data encoder/decoder in the switch to the second operable state when the second subscriber station is determined to be of a type having an audio data encoder/decoder.

4. The switch according to claim 3, wherein the second subscriber station is connected to an intranet, said intranet being connected to said mobile radio communication network via the Internet.

5. The switch according to claim 3, wherein the second subscriber station is connected to an intranet, said intranet being connected to said mobile radio communication network via the Internet and via a public switched telephone network.

6. The switch according to claim 3, wherein the mobile radio communication network is compatible with the Global System for Mobile Communications (GSM), and the audio data is GSM-coded speech data.

7. A telecommunication system comprising:

a) a mobile radio communication network to which a first subscriber station and a second subscriber station are connected, at least one of said first and second subscriber stations having an audio data encoder/decoder, said network including a switch for communicating data between the first and second subscriber stations, said switch comprising;

a1) an audio data encoder/decoder having a first operable state in which digital audio data received from the first or second subscriber station is encoded/decoded, and a second operable state in which digital audio data received from the first or second subscriber station is passed through the switch without encoding/decoding;

a2) means for determining whether the second subscriber station is of a type having an audio data encoder/decoder, said type determining means comprising;

a21) an internal memory for storing calling numbers, associated IP-addresses, and IP-user names for subscriber stations; and

a22) means for comparing entries in the memory with a calling number of the second subscriber station to determine whether the second subscriber station is a station having an audio data encoder/decoder, said calling number of the second subscriber station being included in a call set-up message sent from the first or second subscriber station; and

a3) control means for switching the audio data encoder/decoder in the switch to the second operable state when the second subscriber station is determined to be of the type having an audio data encoder/decoder; and

b) an intranet to which at least the second subscriber station is connected, said intranet being connected to the mobile radio communication network via the Internet and/or a public switched telephone network.

8. The telecommunication system according to claim 7, wherein the mobile radio communication network is compatible with the Global System for Mobile Communications (GSM), and the audio data is GSM-coded speech data.

9. A method for performing data communications between a first subscriber station of a mobile radio communication network and a second subscriber station connectable to the mobile radio communication network, wherein at least the first subscriber station includes an audio data encoding/decoding means, comprising the following steps:

a) sending a call set-up message from the first or second subscriber station to a switching means of the mobile radio communication network to set up a call between the first and second subscriber stations;

b) determining on the basis of said call set-up message whether the second subscriber station is of a type also including an audio data encoding/decoding means;

c) setting up a call between the first and second subscriber station;

d) switching off an audio data encoding/decoding means in said switching means, if the second subscriber station also includes an audio data encoding/decoding means; and

e) encoding/decoding audio data at the first and second subscriber station using the respective encoding/decoding means and communicating said coded audio data through said switching means without applying an audio data coding/decoding thereto in said switching means;

f) wherein the second subscriber station is connected to an intranet, said intranet being connected to said mobile radio communication network via the Internet and via a public switched telephone network; and

g) wherein when said call set-up message is sent from the first subscriber station, said switching means sends an enquiry message to a gateway exchange of said public switched telephone network in order to determine whether the second subscriber station is a station including said audio data encoding/decoding means and being connected to an intranet supporting an IP-network.

10. The method according to claim 9, further comprising sending by the switching means, an enquiry message to said gateway exchange in order to determine whether said call is to be routed through said public switched telephone network or through a direct access unit of said switching means and the Internet to said intranet.

11. A method for performing data communications between a first subscriber station of a mobile radio communication network and a second subscriber station connectable to the mobile radio communication network, wherein at least the first subscriber station includes an audio data encoding/decoding means, comprising the following steps:

a) sending a call set-up message from the first or second subscriber station to a switching means of the mobile radio communication network to set up a call between the first and second subscriber stations;

b) determining on the basis of said call set-up message whether the second subscriber station is of a type also including an audio data encoding/decoding means;

c) setting up a call between the first and second subscriber station;

d) switching off an audio data encoding/decoding means in said switching means, if the second subscriber station also includes an audio data encoding/decoding means; and

e) encoding/decoding audio data at the first and second subscriber station using the respective encoding/decoding means and communicating said coded audio data through said switching means without applying an audio data coding/decoding thereto in said switching means; and

f) wherein the second subscriber station is connected to an intranet, said intranet being connected to said mobile radio communication network via the Internet and via a public switched telephone network; and

g) wherein when said call set-up message is sent from a second subscriber station having an audio data encoding/decoding means, a gateway server compares a calling number of the first subscriber station with entries in a second memory means which is connected to said gateway server and contains calling numbers and an associated IP-address of a direct access unit of said switching means in order to determine whether the first subscriber station belongs to a switching means having a switchable audio data encoding/decoding means.

12. The method according to claim 11, further comprising returning by the gateway server, the IP-address of the direct access unit to the second subscriber station, wherein the second subscriber station directly connects to the direct access unit via said IP-address.

13. A switching means of a mobile radio communication network for communicating data between a first subscriber station of the mobile radio communication network and a second subscriber station connectable to the mobile radio communication network, wherein the first subscriber station includes a first audio data encoding/decoding means, comprising:

a) a second audio data encoding/decoding means having a first operable state in which digital audio data received from the first/second subscriber station is encoded/decoded, and a second operable state in which digital audio data received from the first/second subscriber station is passed through the switch without encoding/decoding;

b) subscriber station type determining means for determining whether the second subscriber station is of a type including an audio data encoding/decoding means on the basis of a call-set-up message sent from the first or second subscriber station during a call set-up phase;

c) control means for switching said audio data encoding/decoding means of said switching means to said second operable state when said subscriber station type determining means determines that the second subscriber station is of a type including an audio data encoding/decoding means;

d) wherein the second subscriber station is connected to an intranet, said intranet being connected to said mobile radio communication network via the Internet and via a public switched telephone network; and

e) first enquiry means are provided for sending an enquiry message to a gateway exchange of said public switched telephone network in order to determine whether the second subscriber station is a station including said audio data encoding/decoding means and being connected to an intranet supporting an IP-network.

14. The switching means according to claim 13, further comprising second enquiry means for sending an enquiry message to said gateway exchange in order to determine whether said call is to be routed through said public switched telephone network or through a direct access unit of said switching means and the Internet to said intranet.

15. A telecommunication system comprising:

a) a mobile radio communication network to which at least one first subscriber station having an audio data encoding/decoding means is connected;

b) an intranet to which at least one second subscriber station is connected;

c) an Internet and/or a public switched telephone network connected between the mobile radio communication network and the intranet;

d) wherein the mobile radio communication network includes a switching means for communicating data between a first subscriber station and a second subscriber station, comprising;

d1) an audio data encoding/decoding means having a first operable state in which digital audio data received from the first/second subscriber station is encoded/decoded, and a second operable state in which digital audio data received from the first/second subscriber station is passed through the switching means without encoding/decoding;

d2) subscriber station type determining means for determining whether the second subscriber station is of a type having an audio data encoding/decoding means on the basis of a call-set-up message sent from the first or second subscriber station during a call set-up phase; and

d3) control means for switching said audio data encoding/decoding means of the switching means to the second operable state when said subscriber station type determining means determines that the second subscriber station is of a type having an audio data encoding/decoding means;

e) wherein said intranet is connected to said mobile radio communication network via the Internet and via a public switched telephone network separately;

f) wherein said switching means further comprises first enquiry means for sending an enquiry message to a gateway exchange of said public switched telephone network in order to determine whether the second subscriber station is a station having said audio data encoding/decoding means and being connected to an Intranet supporting an IP-network.

16. The telecommunication system according to claim 15, wherein said switching means includes second enquiry means for sending an enquiry message to said gateway exchange in order to determine whether said call is to be routed through said public switched telephone network or through a direct access unit of said switching means/and the Internet to said intranet.

17. An exchange in a mobile radio communication network for communicating data between a first subscriber station of the mobile radio communication network and a second subscriber station connectable to the mobile radio communication network, wherein at least the first subscriber station includes a first audio data encoder/decoder said exchange comprising:

a) a second audio data encoder/decoder having a first operable state in which digital audio data received from the first/second subscriber station is encoded/decoded, and a second operable state in which digital audio data received from the first/second subscriber station is passed through the exchange without encoding/decoding;

b) a subscriber station type determiner for determining whether the second subscriber station is of a type having an audio data encoder/decoder, said determiner comprising.

b1) an internal memory for storing calling numbers, associated IP-addresses, and IP-user names for subscriber stations; and

b2) means for comparing entries in the memory with a calling number of the second subscriber station to determine whether the second subscriber station is a station having an audio data encoder/decoder, said calling number of the second subscriber station being included in a call set-up message sent from the first or second subscriber station; and

c) a controller that switches the second audio data encoder/decoder in the exchange to the second operable state when the second subscriber station is determined to be of a type having an audio data encoder/decoder.