Voice over IP (VoIP) Stack

VOIP(4) provides an introductory manual page for VoIP stack components and interfaces. You can also select one of the component or interface sections from the diagram below:

Components

Interfaces

Components

VoIP Stack Manager

This section provides a roadmap to Manual Pages for Voice over IP (VoIP) Stack Manager (VoIP SM).

Bearer Independent Call Control (BICC)

This section provides a roadmap to Manual Pages for Bearer Independent Call Control (BICC).

Session Initiation Protocol Transport (SIPT)

This section provides a roadmap to Manual Pages for Session Initiation Protocol (SIP) Transport (SIP-T).

H.323/225 Call Control

This section provides a roadmap to Manual Pages for H.323/225 Call Control.

CCI-H225

Section: Call Control Interface (CCI) (7)
Updated: Thu, 27 Nov 2008 14:25:17 GMT
Index Return to Main Contents

NAME

CCI-H225 - Call Control Interface - Corregendum for H.225 Conformance

SYNOPSIS

#include <ss7/cci.h>
#include <ss7/h225i.h>
#include <ss7/h225i_ioctl.h>

int h225_stream = open (/dev/h225, flags);

DESCRIPTION

This Corrigendum describes the formats and rules that are specific to ITU-T Recommndation H.225.0. The Corrigendum must be used along with the generic Call Control Interface (cci(7)) as defined in the main document when implementing a CCS provider that will be configured with the H.225.0 call processing layer.

Primitives and Rules for H.225.0 Conformance

The following are the rules that apply to the CCI primitives for H.225.0 compatability.

CALL CONTROL ADDRESSES

The format of the call control address for H.225.0 conforming CCS providers is as follows:

typedef struct h225_addr {
    ulong scope;    /* the scope of the identifier */
    ulong id;       /* the identifier within the scope */
    ulong port;     /* port number */
} h225_addr_t;

scope: conveys the scope of the call control address. See ``Scope'', below.
id: conveys the indentifier within the scope.

Scope

The scope of the address is one of the following:

H225_SCOPE_CT

Conveys that the scope of the call control address is an H.245 transport address. The id within this scope is an IPv4 address which uniquely identifies a reliable signalling channel for carrying the H.245 LCN 0 control for the call. port indicates the IP port number.

An H.245 transport address corresponds to a specific reliable control channel to a transport hosts. Transport connections can be grouped by the host to which they connect.

H.245 transport addresses are identified using an IP address and port number within the CCS provider. Addresses specifying all of the RTP streams controlled by a H.245 control stream are specified with scope H225_SCOPE_CT and the H.245 transport address (IP address in id and IP port number in port).

H225_SCOPE_TP

Conveys that the scope of the call control address is a transport connection. The id within this scope is an identifier which uniquely identifies a reliable signalling channel for a given call.

A transport connection corresponds to a specific reliable signalling channel to a transport host. Transport connections can be grouped by the host to which they connect.

Transport connections are identified using a unique identifier within the CCS provider. Addresses specifying all of the RTP streams controlled by a signalling transport connection are specified with scope H225_SCOPE_TP and the transport connection id.

H225_SCOPE_EP

Conveys that the scope of the call control address is an H.323 endpoints. The id within this scope is an identifier which uniquely identifies a transport endpoint (host).

H225_SCOPE_ZN

Conveys that the scope of the call control address is an H.323 Endpoint zone. The id within this scope is an identifier which uniquely identifies a group of H.323 endpoints all belonging to the same zone.

H225_SCOPE_EG

Conveys that the scope of the call controll address is an H.225 equipment group. The id within this scope is an identifier than uniquely identifies the equipment group to the CCS provider.

An equipment group is a group of all transport addresses terminating at the same location. For Terminal mode, this corresponds to all the transport addresses terminating at the same network provider complex. For Gateway/Gatekeeper mode this corresponds to all the transport addresses terminating on the same customer site.

Equipment groups are identified using a unique equipment group identifier within the CCS provider. Addresses specifying all of the transport addresses making up an equipment group are specified within scope H224_SCOPE_EG and the equipment group id.

H225_SCOPE_XG

Conveys that the scope of the call control address is an exchange group. The id within the scope is an identifier that uniquely identifies the exchange group to the CCS provider.

A exchange group has a different interpretation on the H.323 Terminal and Gateway/Gatekeeper side of the call control interface. In Terminal mode, the provider group is a group of all zones which are serviced by the same network provider. In Gateway/Gatekeeper mode, the customer group is a group of all equipment groups to which the same service is provided to the same customer by the network.

Exchange provider groups are identified using a unique exchange group identifier within the CCS provider. Addresses specifying all of the equipment groups is an exchange group are specified with scope H225_SCOPE_XG and the exchange group id.

H225_SCOPE_DF

Conveys that the scope of the call control adress is the default scope. The id within the scope is unused and should be ignored by the CCS user and will be coded zero (0) by the CCS provider.

Rules

Rules for scope:

---: In primitives in which the address parameter occurs, the scope field setting indicates the scope of the address parameter.
---: Only one call control address can be specified within a single scope.
---: Not all scopes are necessarily supported by all primitives. See the particular primitive, below.

Rules for addresses:

---

The address contained in the primitive contains the following:

*: A scope.
*: An identifier within the scope or zero (0).

---

If the scope of the address is H225_SCOPE_DF, then the id and port fields should be coded zero (0) and will be ignored by the CCS user or provider.

---

If the scope of the address is H225_SCOPE_EP, then the port field should be coded all zeros (0) and will be ignored by the CCS user or provider.

---

In all other scopes, the port number is optional and coded zero (0) if unused.

OPTIONAL PARAMETERS

Format

The format of the optional parameters for H.225.0 conforming CCS providers is as follows:

Parameters

cc_opt_length: Conveys the length of the optional parameters associated with the primitive. For H.225.0 conforming CCS providers, the format of the optional parameters is the format Information Elements of the H.225.0 message (including the tag and length octets) as specified in H.225.0.
cc_opt_offset: Conveys the offset of the optional parameters from the beginning of the block.

Rules

Rules for optional parameters:

---: The optional parameters provided by the CCS user may be checked for syntax by the CCS provider. If the CCS provider discovers a syntax error in the format of the optional parameters, the CCS provider should respond with a CC_ERROR_ACK(7) primitive with error [CCBADOPT].
---: For some primitives, specific optional parameters might be interpreted by the CCS provider and alter the function of some primitives. See the specific primitive descriptions layer in this Corrigendum.
---: Except for optional parameters interpreted by the CCS provider as specified later in this Corrigendum, the optional parameters are treated as opaque and the optional parameter lis is only checked for syntax. Opaque parameters will be passed to the H.225 message without examination by the CCS provider.
---: To perform specific functions, additional mandatory or optional parameters ma be added to the H.225 message by the CCS provider.
---: To perform specfic functions, optional parameters may be modified by the CCS provider before being added to the H.225 message.

Service Primitives

Local Management Primitives

CC_INFO_REQ(7)
CC_INFO_ACK(7)
CC_BIND_REQ(7)
CC_BIND_ACK(7)
CC_OPTMGMT_REQ(7)
CC_OPTMGMT_ACK(7)

Call Setup Primitives

CC_SETUP_REQ(7)
CC_SETUP_IND(7)
CC_SETUP_RES(7)
CC_SETUP_CON(7)
CC_CALL_REATTEMPT_IND(7)
CC_SETUP_COMPLETE_REQ(7)
CC_SETUP_COMPLETE_IND(7)

Continuity Check Primitives

CC_CONT_CHECK_REQ(7)
CC_CONT_CHECK_IND(7)
CC_CONT_TEST_REQ(7)
CC_CONT_TEST_IND(7)
CC_CONT_REPORT_REQ(7)
CC_CONT_REPORT_IND(7)

Call Establishment Primitives

CC_MORE_INFO_REQ(7)
CC_MORE_INFO_IND(7)
CC_INFORMATION_REQ(7)
CC_INFORMATION_IND(7)
CC_INFO_TIMEOUT_IND(7)
CC_PROCEEDING_REQ(7)
CC_PROCEEDING_IND(7)
CC_ALERTING_REQ(7)
CC_ALERTING_IND(7)
CC_PROGRESS_REQ(7)
CC_PROGRESS_IND(7)

Call Established Primitives

CC_SUSPEND_REQ(7)
CC_SUSPEND_IND(7)
CC_SUSPEND_RES(7)
CC_SUSPEND_CON(7)
CC_SUSPEND_REJECT_REQ(7)
CC_SUSPEND_REJECT_IND(7)
CC_RESUME_REQ(7)
CC_RESUME_IND(7)
CC_RESUME_RES(7)
CC_RESUME_CON(7)
CC_RESUME_REJECT_REQ(7)
CC_RESUME_REJECT_IND(7)

Supplementary Services Primitives

CC_FACILITY_REQ(7)
CC_FACILITY_IND(7)
CC_HOLD_REQ(7)
CC_HOLD_IND(7)
CC_HOLD_RES(7)
CC_HOLD_CON(7)
CC_RETRIEVE_REQ(7)
CC_RETRIEVE_IND(7)
CC_RETRIEVE_RES(7)
CC_RETRIEVE_CON(7)
CC_REGISTER_REQ(7)
CC_REGISTER_IND(7)

Call Termination Primitives

CC_REJECT_IND(7)
CC_CALL_FAILURE_IND(7)
CC_DISCONNECT_REQ(7)
CC_DISCONNECT_IND(7)
CC_RELEASE_REQ(7)
CC_RELEASE_IND(7)

Management Primitives

CC_RESTART_REQ(7)
CC_RESET_REQ(7)	(not used)
CC_RESET_IND(7)	(not used)
CC_RESET_RES(7)	(not used)
CC_RESET_CON(7)	(not used)
CC_BLOCKING_REQ(7)	(not used)
CC_BLOCKING_IND(7)	(not used)
CC_BLOCKING_RES(7)	(not used)
CC_BLOCKING_CON(7)	(not used)
CC_UNBLOCKING_REQ(7)	(not used)
CC_UNBLOCKING_IND(7)	(not used)
CC_UNBLOCKING_RES(7)	(not used)
CC_UNBLOCKING_CON(7)	(not used)
CC_QUERY_REQ(7)	(not used)
CC_QUERY_IND(7)	(not used)
CC_QUERY_RES(7)	(not used)
CC_QUERY_CON(7)	(not used)

Maintenance Primitives

CC_MAINT_IND(7)

FILES

<ss7/cci.h>, <ss7/bssapi.h>, <ss7/bssapi_ioctl.h>.

DEVICES

/dev/bssap.

REFERENCES

[1]: ITU-T Recommendation H.225.0, Media Stream Packetization and Synchronization on Non-Guaranteed Quality of Service LANs, November 1996, (Geneva), ITU, ITU-T Telecommunication Standardization Sector of ITU. (Previously "CCITT Recommendation") <http://www.itu.int/rec/T-REC-H.225/>
[2]: ITU-T Recommendation H.323, Packet-Based Multimedia Communications Systems, February 1998, (Geneva), ITU, ITU-T Telecommunication Standardization Sector of ITU. (Previously "CCITT Recommendation") <http://www.itu.int/rec/T-REC-H.323/>
[3]: ITU-T Recommendation H.245, Control Protocol for Multimedia Communication, March 1996, (Geneva), ITU, ITU-T Telecommunication Standardization Sector of ITU. (Previously "CCITT Recommendation") <http://www.itu.int/rec/T-REC-H.245/>