Substitution call control system in ATM communication network
A substitution call control system includes an ATM (Asynchronous Transfer Mode) subscriber network of an ATM communication network. The ATM subscriber network includes a plurality of network terminators respectively connected with a plurality of subscriber terminals, and an ATM subscriber line concentrator, which accommodates VCs (Virtual Connection) to the plurality of network terminators, and is connected with a ATM switching apparatus of the ATM network through a UNI (User-Network Interface). The ATM subscriber line concentrator includes a substitution call control function to substitute for the plurality of network terminators and the subscriber terminals for a call control.
1. A substitution call control system including an ATM (Asynchronous Transfer Mode) subscriber network of an ATM communication network, said ATM subscriber network comprising:
a plurality of network terminators respectively connected with a plurality of subscriber terminals; and
an ATM subscriber line concentrator which accommodates VCs (Virtual Connection) to said plurality of network terminators, and is connected with a ATM switching apparatus of said ATM network through a UNI (User-Network Interface), and
wherein said ATM subscriber line-concentrator includes a substitution call control function to substitute for said plurality of network terminators and said subscriber terminals for a call control and
wherein said plurality of network terminators and said plurality of subscriber terminals do not have call control functions.
2. A substitution call control system according to claim 1 , wherein when one of said plurality of subscriber terminals issues a call processing request to said ATM subscriber line concentrator through a corresponding one of said plurality of network terminators, a line number connected to said one subscriber terminal and an ATM address of said one network terminator or said one subscriber terminal are held.
3. A substitution call control system according to claim 1 , wherein when one of said plurality of subscriber terminals issues a call processing request to said ATM subscriber line concentrator through a corresponding one of said plurality of network terminators, a call number is held.
4. A substitution call control system according to claim 1 , wherein when a SVC (Switched Virtual Channel) connection is established in response to a call processing request issued from one of said plurality of subscriber terminals to said ATM subscriber line concentrator through a corresponding one of said plurality of network terminators, a VPI (Virtual Path Identifier) value and a VCI (Virtual Channel Identifier) value of said SVC connection are held.
5. A substitution call control system according to claim 1 , wherein said ATM subscriber line concentrator and each of said plurality of subscriber terminals are connected by a PVC (Permanent Virtual Circuit) connection to allow a substitution call control message to be transmitted and received.
6. A substitution call control system according to claim 1 , wherein said ATM subscriber line concentrator and each of said plurality of network terminators are connected by a PVC (Permanent Virtual Circuit) connection to allow a substitution call control message to be transmitted and received.
7. A substitution call control system according to claim 5 , wherein a VPI/VCI value (a value of VP identifier/VC identifier) of said PVC connection is 0/5.
8. A substitution call control system according to claim 6 , wherein a VPI/VCI value (a value of VP identifier/VC identifier) of said PVC connection is 0/5.
9. A substitution call control system according to claim 5 , wherein said substitution call control message is transmitted and received in a same protocol as that for a subscriber data.
10. A substitution call control system according to claim 6 , wherein said substitution call control message is transmitted and received in a same protocol as that for a subscriber data.
11. A substitution call control system according to claim 5 , wherein said substitution call control message is transmitted and received by a Classical IP and ARP over ATM system defined in IETF (Internet Engineering Task Force) RFC (Request For Comment) 1577.
12. A substitution call control system according to claim 6 , wherein said substitution call control message is transmitted and received by a Classical IP and ARP over ATM system defined in IETF (Internet Engineering Task Force) RFC (Request For Comment) 1577.
13. A substitution call control system according to claim 5 , wherein said substitution call control message is transmitted and received by an xDSL over ATM system through a PVC connection, wherein said xDSL is a general term of various typea of DSL (Digital Subscriber Line, and includes an Asymmetric DSL, a high-bit-rate DSL, a Rate-Adaptive DSL, a Symmetrical DSL and a Very-high-bit-rate DSL).
14. A substitution call control system according to claim 6 , wherein said substitution call control message is transmitted and received by an xDSL over ATM system through a PVC connection, wherein said xDSL is a general term of various type of DSL (Digital Subscriber Line, and includes an Asymmetric DSL, a high-bit-rate DSL, a Rate-Adaptive DSL, a Symmetrical DSL and a Very-high-bit-rate DSL).
15. A substitution call control system according to claim 1 , wherein each of said plurality of subscriber terminals and a corresponding one of said plurality of network terminators are connected in IEEE 802.3 ether network.
16. A substitution call control system according to claim 1 , wherein each of said plurality of subscriber terminals and a corresponding one of said plurality of network terminators are connected by a PVC (Permanent Virtual Circuit) connection.
17. A substitution call control system according to claim 16 , wherein a VPI/VCI value (a value of VP identifier/VC identifier) of said PVC connection is 0/5.