Feature transparency in a telecommunications network

• US 6,650,632 B1
• Filed: 06/30/1998
• Issued: 11/18/2003
• Est. Priority Date: 06/30/1998
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Kingston, Adrian, Volftsun, Lev, Rednor, Fred R., West, Andrew, Neighbors, Clay H., Rabinovitch, Mikhail
• Primary Examiner(s): Chin, Wellington
• Assistant Examiner(s): PHAM, BRENDA H
• Application Number:
  US09/106,449
• Time in Patent Office: 1,967 Days
• Field of Search: 370/352, 370/353, 370/354, 370/355, 370/356, 370/465, 370/466, 370/467
• US Class Current: 370/352
• CPC Class Codes: H04L 12/4641 Virtual LANs, VLANs, e.g. virtual private networks [VPN] LAN interconnection over a bridge based backbone H04L12/462; encapsulation techniques H04L12/4633; routing of packets H04L45/00; packet switches H04L49/00; virtual private networks for security H04L63/0272
• CPC Class Codes: H04L 12/5692 Selection among different networks
• CPC Class Codes: H04M 7/009 in systems involving PBX or KTS networks
• CPC Class Codes: H04Q 3/0029 Provisions for intelligent networking

Abstract

An auxiliary communication network is introduced into a virtual private network for passing signaling messages that present features not supported by the public, primary communication network portion of the virtual private network. Protocol converters are positioned within the virtual private network to intercept signaling messages, establish a connection through the auxiliary network, determine whether the intercepted messages present unsupported features, and, in which case, route corresponding feature requested through the auxiliary communication network. Preferably, the auxiliary network connection is established in a direction reverse to and in response to the primary network connection.

Claims

1. A custom call feature transmission apparatus for use with a first private network that is connected to a second private network by a communication network employing a protocol incapable of supporting at least one custom calling feature supported by the first private network and the second private network, the apparatus comprising:

a first communications interface coupled between the first private network and the communication network so as to communicate information therebetween;

a second communications interface coupled between the first private network and an auxiliary network so as to communicate messages in the protocol that use the at least one custom calling feature that is a special service function of a telephone service that is additional to basic transmission of sound;

a processor coupled to the first communications interface and the second communications interface; and

a memory coupled to the processor, the memory comprising one or more instructions which, when executed by the processor, cause the processor to perform the steps of;

intercepting a message directed from the first private network to the second private network;

determining whether the message uses the at least one custom calling feature;

establishing a first connection through the communication network to the second private network;

in response to determining that the message uses the at least one custom calling feature, transmitting a request for the at least one custom calling feature to the second private network; and

accepting an establishment of a second connection through the auxiliary network from said second private network in response to the message from the first private network.

2. The apparatus of claim 1, wherein the step of establishing a first connection includes the step of transmitting a connection request message including a device identifier indicative of the apparatus through the communication network to the second private network and wherein the step of accepting the establishment of a second connection through the auxiliary network from said second private network is according to the connection request message.

3. The apparatus of claim 1, wherein the memory further comprises instructions that cause the processor to perform the steps of:

accepting an establishment of a first connection through said communication network from said second private network;

in response to said accepting an establishment of a first connection, establishing a second connection through the auxiliary network to said second private network.

4. The apparatus of claim 2, wherein:

the step of establishing the first connection through the communication network to the second private network includes the step of receiving a connection request message including a device identifier indicative of a telecommunication device that is associated with said first connection; and

the step of accepting an establishment of a second connection through the auxiliary network to the second private network includes the steps of;

determining an address for the telecommunications device based on the device identifier; and

establishing said second connection based on the address.

5. A telecommunications network comprising:

a first private network capable of supporting a custom calling feature that is a special service function of a telephone service that is additional to basic transmission of sound;

a first protocol converter coupled to said first private network;

a first communication network coupled to said first protocol converter and employing a protocol incapable of supporting said custom calling feature;

a second protocol converter coupled to said first communication network;

a second private network capable of supporting said custom calling feature coupled to said second protocol converter; and

a second communication network coupled to said first protocol converter and said second protocol converter for supporting said custom calling feature;

wherein said first protocol converter is configured to establish a first connection from said first private network to said second private network through said first communication network;

wherein said second protocol converter is configured to establish a second connection from said second private network to said first private network through said second communication network in response to said first connection being established;

wherein said first protocol converter is configured to transmit a connection request message including a device identifier indicative of said first protocol converter through said first communication network to said second protocol converter; and

wherein said second protocol converter is configured, in response to receiving said connection request message, to determine an address for said first protocol converter based on said device identifier and establish said second connection based on said address.

6. A telecommunications network comprising:

a first private network capable of supporting a custom calling feature that is a special service function of a telephone service that is additional to basic transmission of sound;

a first protocol converter coupled to said first private network;

a first communication network coupled to said first protocol converter and employing a protocol incapable of supporting said custom calling feature;

a second protocol converter coupled to said first communication network;

a second private network capable of supporting said custom calling feature coupled to said second protocol converter; and

a second communication network coupled to said first protocol converter and said second protocol converter for supporting said custom calling feature;

wherein said first protocol converter is configured to

(a) receive a signaling message from said first private network;

(b) determine whether said signaling message includes a custom calling feature request not supported by the protocol of said first communication network, wherein the custom calling feature is a special service function of a telephone service that is additional to basic transmission of sound; and

(c) if said signaling message includes a calling feature request not supported by the protocol of said first communication network, then transmit said custom calling feature request to said second private network through said second communication network.

7. The telecommunications network of claim 6, wherein said second protocol converter is configured to:

(1) receive a signaling message from said second private network;

(2) determine whether said signaling message includes a custom calling feature request not supported by the protocol of said first communication network, wherein the custom calling feature is a special service function of a telephone service that is additional to basic transmission of sound; and

(3) if said signaling message includes a calling feature request not supported by the protocol of said first communication network, then transmit said custom calling feature request to said first private network through said second communication network.

8. In a virtual private network including a first private network and a second private network connected by a first communication network employing a protocol incapable of supporting at least one custom calling feature supported by said first private network and said second private network, a method of transmitting a signaling message, requesting said at least one custom calling feature that is a special service function of a telephone service that is additional to basic transmission of sound, from said first private network to said second private network, said method comprising the steps of:

establishing a first connection through said first communication network between said first private network and said second private network;

in response to establishing said first connection, establishing a second connection between said first private network and said second private network through a second communication network; and

transmitting said custom calling feature, which is a special service function of a telephone service that is additional to basic transmission of sound, between said first private network and said second private network through said second communication network.

9. The method of claim 8, wherein the step of establishing a first connection includes the step of transmitting a connection request message including a device identifier indicative of a protocol conversion unit coupling said first private network to said first communication network and said second communication network.

10. The method of claim 9, wherein the step of establishing a second connection includes the steps of:

determining an address for said first protocol converter based on said device identifier; and

establishing said second connection based on said address.

11. The method of claim 8, further comprising the steps of:

receiving a signaling message from one of said first private network and said second private network;

determining whether said signaling message includes a custom calling feature request not supported by the protocol of said first communication network, wherein the custom calling feature is a special service function of a telephone service that is additional to basic transmission of sound; and

if said signaling message includes said custom calling feature request, then transmitting said custom calling feature request to another of said first private network and said second private network through said second communication network.

12. A telecommunications device for supporting calling feature transparency in a virtual private network including a first private network and a second private network connected by a first communication network employing a protocol incapable of supporting at least one custom calling feature supported by said first private network and said second private network, said telecommunications device comprising:

a computer system including a plurality of input/output cards; and

a channel multiplexer coupled to said plurality of input/output cards, said first private network, said first communication network, and to a second communication network, wherein said second communication network is further coupled to said second private network;

wherein said computer system is configured to perform the steps of;

intercepting a signaling message for said second private network from the first private network;

determining whether said signaling message includes a custom calling feature request not supported by the protocol of said first communication network, wherein the custom calling feature is a special service function of a telephone service that is additional to basic transmission of sound; and

if said signaling message includes said custom calling feature request, then transmitting said custom calling feature request to said second private network.

13. The telecommunications device of claim 12, wherein said computer system is further configured to perform the steps of:

establishing a first connection through said first communication network to said second private network; and

accepting an establishment of a second connection through said second communication network from said second private network.

14. The telecommunications device of claim 13, wherein the step of establishing a first connection through said first communication network to said second private network includes the step of transmitting a connection request message including a device identifier indicative of said telecommunications device through said first communication network to said second private network.

15. The telecommunications device of claim 12, wherein said computer system is further configured to perform the steps of:

accepting an establishment of a first connection through said first communication network from said second private network;

in response to said accepting an establishment of a first connection, establishing a second connection through said second communication network to said second private network.

16. The telecommunications device of claim 15, wherein:

the step of accepting an establishment of a first connection through said first communication network from said second private network includes the step of receiving a connection request message including a device identifier indicative of a second telecommunication device associated with said first connection; and

the step of establishing a second connection through said second communication network to said second private network includes the steps of;

determining an address for the second telecommunications device based on the device identifier; and

establishing said second connection based on said address.

17. A computer-readable medium bearing instructions for supporting calling feature transparency in a virtual private network including a first private network and a second private network connected by a first communication network employing a protocol incapable of supporting at least one custom calling feature supported by said first private network and said second private network, said instructions arranged, when executed, to cause a telecommunications device, including a computer system coupled to said first private network, said first communication network, and further coupled to a second communication network, to perform the steps of:

intercepting a signaling message for said second private network from the first private network;

determining whether said signaling message includes a custom calling feature request not supported by the protocol of said first communication network, wherein the custom calling feature is a special service function of a telephone service that is additional to basic transmission of sound;

establishing a first connection through said first communication network to said second private network;

if said signaling message includes said custom calling feature request, then transmitting said custom calling feature request to said second private network through the second communication network; and

accepting an establishment of a second connection through said second communication network from said second private network.

18. The computer-readable medium of claim 17, wherein the step of establishing a first connection through said first communication network to said second private network includes the step of transmitting a connection request message including a device identifier indicative of said telecommunications device through said first communication network to said second private network.

19. A computer-readable medium bearing instructions for supporting calling feature transparency in a virtual private network including a first private network and a second private network connected by a first communication network employing a protocol incapable of supporting at least one custom calling feature supported by said first private network and said second private network, said instructions arranged, when executed, to cause a telecommunications device, including a computer system coupled to said first private network, said first communication network, and further coupled to a second communication network, to perform the steps of:

intercepting a signaling message for said second private network from the first private network;

accepting an establishment of a first connection through said first communication network from said second private network;

in response to said accepting an establishment of a first connection, establishing a second connection through said second communication network to said second private network;

determining whether said signaling message includes a custom calling feature request not supported by the protocol of said first communication network, wherein

the custom calling feature is a special service function of a telephone service that is additional to basic transmission of sound;

if said signaling message includes said custom calling feature request, then transmitting said custom calling feature request to said second private network through the second communication network.

20. The computer-readable medium of claim 19, wherein:

the step of accepting an establishment of a first connection through said first communication network from said second private network includes the step of receiving a connection request message including a device identifier indicative of a second telecommunication device associated with said first connection; and

the step of establishing a second connection through said second communication network to said second private network includes the steps of;

determining an address for the second telecommunications device based on the device identifier; and

establishing said second connection based on said address.