Internet Engineering Task Force V.Bajaj Internet Draft K.Laha Document: draft-hss-megaco-r1package-00.txt Hughes Software Systems April 11, 2000 Expires october 11, 2000 Megaco/H.248 R1 Package Status of this document This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026 [ ]. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet- Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. 1. Abstract This document is work in progress and defines the MF package in association with the Megaco/H.248 Protocol that can be used to control a Media Gateway (MG) from an external controller, called a Media Gateway controller (MGC). It is intended to satisfy the requirements in section 12 of the Megaco/H.248 requirement document [ ]. 2. Conventions used in this document The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC-2119 [ ]. 3. Document Organization Bajaj,Laha [page 1] Internet Draft Megaco/H.248 R1 Package April 11, 2000 The subsequent portion of this draft is organized into the following major sections: * Introduction to R1 signaling * Assumptions * Description of the R1 package * References * Author's Address 4. Introduction to R1 signaling Signaling System R1 [ ] may be applied for automatic and semi-automatic operation of one-way or both-way circuits, within an international region. It employs both line and register signaling to convey supervisory and address signals respectively. Signaling System R1 transmits supervisory signals, link-by-link, using a single frequency in-band continuous tone for analogue working. The presence or absence of this frequency on the line indicates a specific signal. The line signaling on PCM systems is channel associated. The register signaling uses link-by-link multi-frequency (MF) in-band pulse signaling for the transmission of address signals. The address signals follow a 2-out-of-6 frequency combination preceded by a start-of-pulsing indication (KP) and terminated by an end-of-pulsing indication (ST). 5. Assumptions The following draft assumes the support of ITU-T compliant [4] R1 signaling only. R1 defines a "delay-dialing" backward line signal to acknowledge the "seizing" forward signal and delay the attachment of registers at the outgoing end till registers are attached at the incoming end for collecting address signals. When registers are attached at the incoming end and it is ready to receive address signals, the incoming end sends the "start-dialing"/"proceed-to-send" signal to the outgoing end. The "start-dialing" signal is simply an indication to start out-pulsing the address signals and it is sufficient that the interpretation of this signal remains confined to MG and is not needed to be routed to MGC as an event. Hence the event reporting "delay-dialing" to MGC is equivalent to an acknowledgement to the signal that generates "seizing" signal on the trunk. The KP and ST signals which form the pre-amble and post-amble of the inter-register signaling, can also be confined to MG which it attaches Bajaj,Laha [page 2] Internet Draft Megaco/H.248 R1 Package April 11, 2000 or strips on its own without the MGC bothering about the same. The MGC only sends the digit information and collects the same from MG. 6. R1 Package Description 6.1 Package Package Name: R1 Package Package ID: r1 (To be allocated through IANA) Description: This package is used to handle signals and events on terminations supporting Signaling System R1 between the Media Gateway and the PSTN network. Version: 1 Extends: None 6.2 Properties None defined by this package 6.3 Events 6.3.1 Event Name: Seizure EventID: sz (0x0001) Description: The Seizure event shall be reported when an incoming R1 "Seizing" signal occurs on the termination and an events descriptor is activated that requests the Seizure event. The line signal condition against which the "Seizing" signal is verified is provisioned in the MG. EventsDescriptor Parameters: Parameter Name: Seize signal validation time Parameter id: sztim (0x0001) Description: specifies the minimum duration for which the "Seizing" signal must persist for the same to be reported as an event. Gateway shall have default value for this timer. Type: integer, in milliseconds Possible values: 0 and up ObservedEventsDescriptor Parameters: none defined by this package 6.3.2 Event Name: Seizure Acknowledge EventID: sa (0x0002) Description: The Seizure Acknowledge event shall be reported when an incoming R1 line signal "delay-dialing" occurs on the termination in response to an outgoing "Seizing" signal already sent and an events descriptor is activated that requests the Seizure Acknowledge event. The line signal condition against which the "delay-dialing" signal is verified is provisioned in the MG. Bajaj,Laha [page 3] Internet Draft Megaco/H.248 R1 Package April 11, 2000 EventsDescriptor Parameters: none defined by this package ObservedEventsDescriptor Parameters: none defined by this package 6.3.3 Event Name: Answer EventID: ans (0x0003) Description: The Answer event shall be reported when an incoming R1 line signal "Answer" occurs on the termination and an events descriptor is activated that requests the Answer event. The line signal condition against which the "Answer" signal is verified is provisioned in the MG. EventsDescriptor Parameters: none defined by this package ObservedEventsDescriptor Parameters: none defined by this package 6.3.4 Event Name: Clear EventID: clr (0x0004) Description: The Clear event shall be reported when an incoming R1 line signal "Clear-forward" or "Clear-back" occurs on the termination and the an events descriptor is activated that requests the Clear event. Whether "Disconnect" or "Hang-up" shall depend on the end initiating the call clearing. The line condition against which either of the signals is verified is provisioned in the MG. EventsDescriptor Parameters: Parameter Name: Clear-forward signal validation time Parameter id: clftim (0x0001) Description: specifies the minimum duration for which the Gateway if behaving as an incoming end, validates the "clear-forward" signal before declaring it as a Clear event reportable to MGC. This validation time differs depending on whether registers have been attached or not. Gateway shall have default value for this timer. Type: integer, in milliseconds Possible values: 0 and up ObservedEventsDescriptor Parameters: none defined by this package Bajaj,Laha [page 4] Internet Draft Megaco/H.248 R1 Package April 11, 2000 6.3.5 Event Name: Address EventID: addr (0x0005) Description: Detects the complete R1 address information as received through register signaling. The event shall be reported after collecting the complete address digits and an events descriptor is activated requesting the Address event. The address digits shall be collected as per a digitmap. The actual frequency, cadence, duration and amplitude values against which the multi-frequency tones that convey the address information are validated are provisioned in the MG. EventsDescriptor Parameters: none defined by this package ObservedEventsDescriptor Parameters: Parameter Name: Digit String ParameterID: ds (0x0001) Description: The portion of the collected address digits which matched part or all of an alternative event sequence specified in the digit map. Type: string of digits (possibly empty) returned as a quoted string. Possible Values: a sequence of the characters "0" through "9" Parameter Name: Termination Method ParameterID: tm (0x0002) Description: indicates the reason for the generation of the Address event. Type: enumeration Possible Values: "UM" (0x0001) Unambiguous Match "PM" (0x0002) Partial Match, completion by timer expiry or unmatched event "FM" (0x0003) Full Match, completion by timer expiry or unmatched event 6.3.6 Event Name: Failure EventID: fail (0x0006) Description: Reports a failure condition in the working of the R1 line or register signaling when an events descriptor is activated requesting the Failure event. EventsDescriptor Parameters: none defined by this package ObservedEventsDescriptor Parameters: Parameter Name: Error code Bajaj,Laha [page 5] Internet Draft Megaco/H.248 R1 Package April 11, 2000 ParameterID: ec (0x0001) Description: describes the failure reason Type: enumeration Possible Values: "ULS" (0x0001) Unexpected line signal "LTO" (0x0002) Line signal timeout "RTO" (0x0003) Register signal timeout "SME" (0x0004) Protocol State machine malfunction 6.4 Signals 6.4.1 Signal Name: Seizure SignalID: sz (0x0001) Description: Applies a "Seizing" signal on the R1 termination. The line signal that is actually sent on the physical termination is provisioned in the MG. Signal Type: (OO) on/off Duration: Not applicable Additional Parameters: None 6.4.2 Signal Name: Seizure Acknowledge SignalID: sa (0x0002) Description: Applies "delay-dialing" in response to "seizing" signal and "start-dialing" once the registers are ready to receive the address digits. The line condition that is actually sent on the physical termination is provisioned in the MG. Signal Type: (OO) on/off Duration: Not applicable Additional Parameters: None 6.4.3 Signal Name: Answer SignalID: ans (0x0003) Description: Applies an "Answer" signal on the R2 termination. The line condition that is actually sent on the physical termination is provisioned in the MG. Signal Type: (OO) on/off Duration: Not applicable Additional Parameters: None 6.4.4 Signal Name: Clear SignalID: clr (0x0004) Description: Applies a "Clear-forward" or a "Clear-back" signal depending on whether the Gateway represents the outgoing or incoming side for the call on the concerned physical termination (R1 trunk). The line condition that is actually sent on the physical termination Bajaj,Laha [page 6] Internet Draft Megaco/H.248 R1 Package April 11, 2000 is provisioned in the MG. Signal Type: (OO) on-off Duration: Provisioned 6.4.5 Signal Name: Address SignalID: addr (0x0005) Description: Applies the address signals in the form of MF-tones on the R1 trunk. The actual frequency, cadence, duration and amplitude values for the multi-frequency tones that convey the address information are provisioned in the MG. Signal Type: (BR) Brief Duration: Provisioned Additional Parameters: Parameter Name: Digit String ParameterID: ds (0x0001) Description: The digit string that needs to be sent as address signals. Type: string of digits. Possible Values: a sequence of the characters "0" through "9" 6.5 Statistics none 6.6 Procedures None 7. References 8. Author's Addresses Vikas Bajaj Hughes Software Systems,Ltd. Gurgaon,Haryana,India. 122015. Ph: (91)-11-6346666.Ex-2804. Fax: (91)-124-6342810 or 811. mEmail: vbajaj@hss.hns.com. Kushanava Laha Hughes Software Systems,Ltd. Gurgaon,Haryana,India. 122015. Ph: (91)-11-6346666.Ex-3083 Email: klaha@hss.hns.com. Bajaj,Laha [page 7] Internet Draft Megaco/H.248 R1 Package April 11, 2000 Full Copyright Statement "Copyright (C) The Internet Society (April,2000). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into 1. Bradner, S., "The Internet Standards Process -- Revision 3", BCP 9, RFC 2026, October 1996. 2. Draft Recommendation H.248 (February 2000), Temporary Document 37 (PLEN), Study Group 16, ITU-Telecommunication Standardization Sector (to be issued as draft-ietf-megaco-protocol-07.txt) 3. Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997 4. Specifications of Signaling System R1, Q.310-Q.331, Blue Book, CCITT