SS7 SCCP User Adaptation Layer (SUA)

SUA

Section: The OpenSS7 Project Devices (4)
Updated: Mon, 15 Dec 2008 06:21:59 GMT
Index Return to Main Contents

NAME

SUA - SS7 SCCP User Adaptation Layer (SUA)

SYNOPSIS

#include <ss7/sccpi.h>
#include <ss7/sccpi_ioctl.h>
#include <ss7/sua_ioctl.h>

int sua_stream = open(device, flags);
int sua_xtistr = t_open(device, flags);
int sua_socket = socket(PF_SS7, socket_type, SS7PROTO_SUA);

DESCRIPTION

SUA
is an implementation of the SS7 SCCP User Adaptation Layer (SUA) defined in draft-ietf-sigtran-sua-14.txt. SUA provides a back haul of the services of the sccp(4) over an IP network using Stream Control Transmission Protocol, sctp(4), as defined in RFC 2960[1]. In addition it provides a building block of redundant and distributed SS7 systems. (See ``NOTICES'', below.)

SUA is implemented as a STREAMS(4) multiplexing driver. sccp(4) or sctp(4) streams are linked under the SUA multiplexing driver using the I_LINK or I_PLINK commands of streamio(7), to provide transport or direct SCCP services to SUA. Once linked, the streams must be configured using sua_ioctl(4).

SUA provides the following stream types that are directly compatible with the stream types provided by sccp(4). To select one of these stream types, device can be one of the following:

/dev/sua: This device provides the SCCP protocol service interface using the N-primitives of the Signalling Connection Control Part Interface described in sccpi(7). This interface is suitable for use with other SS7 modules and drivers.
/dev/sua-npi-cl, /dev/sua-npi-co: This device provides the SCCP protocol service interface using the N-primitives of the Network Provider Interface[2], npi(7), used for the Signalling Connection Control Part as described in sccp_npi(7). The npi(7) interface provided on a stream opening this device is suitable for use with the sockets(3) library and provides the SCCP interface using sockets as described in sccp_socket(7).
/dev/sua-npi-cl provides a connectionless N_CLNS network service provider supporting protocol classes 0 and 1; /dev/sua-npi-co provides a connection oriented N_CONS newtork service provider supporting protocol classes 2 and 3.
/dev/sua-tpi-cl, /dev/sua-tpi-co: This device provides the SCCP protocol service interface using the T-primitives of the Transport Provider Interface[3], tpi(7), used for the Signalling Connection Control Part as described in sccp_tpi(7). The tpi(7) interface provided on a stream opening this device is a suitable device for use with the xnet(3) or xti(3) library t_open(3) call and provides the SCCP interface using XTI[4, 5] as described int xti_sccp(3).
/dev/sua-tpi-cl provides a connectionless T_CLTS transport service provider supporting protocol classes 0 and 1; /dev/sua-tpi-co provides a connection oriented T_COTS transport service provider supporting protocol classes 2 and 3.

SUA provides three socket types by use of the sockets(3) library socket(3) call. SUA provides sockets in the protocol family PF_SS7 using the protocol number SS7PROTO_SUA. The socket_type argument can be one of the following:

SOCK_DGRAM: Provides a connection-less datagram services without regard to order. This is an SCCP protocol class 0 service provider. This socket uses the underlying /dev/sua-tpi-cl transport service provider.
SOCK_RDM: Provides a connection-less reliable datagram service without regard to order. This is an SCCP protocol class 1 service provider. This socket uses the underlying /dev/sua-tpi-cl transport service provider.
SOCK_SEQPACKET: Provides a connection-oriented reliable datagram service with or without receipt confirmation and flow control. This is an SCCP protocol class 2 or 3 service provider. This socket uses the underlying /dev/sua-tpi-co transport service provider.

The following entries in /etc/protosw provides the information necessary for socksys(4) to use these devices:

PF_SS7	SOCK_DGRAM	SS7PROTO_SUA	/dev/sua-tpi-cl	tpi	clts
PF_SS7	SOCK_RDM	SS7PROTO_SUA	/dev/sua-tpi-cl	tpi	clts
PF_SS7	SOCK_SEQPACKET	SS7PROTO_SUA	/dev/sua-tpi-cl	tpi	cots

For additional information, see protosw(5).

NOTICES

SUA can be configured on a system as a drop in transparent replacement for sccp(4). In such a configuration, users opening streams or sockets as defined in sccp(4) will be opening sua streams and sockets, but will be unaware of the difference. In OpenSS7 sua is used as the primary mechanism of redundnacy and distribution and, when properly configured (see sua(8)), sua functions transparently to the SCCP-User.

Also, opening and binding an sua stream or socket may result in the opening and binding of an sccp(4) stream on the local or remote host in direct support of the local SCCP-User.

IOCTLS

All interfaces support a set of management IO controls using ioctl(2) system calls on the sua_stream, sua_xtistr or sua_socket file descriptor or socket. These management controls are documented in sua_ioctl(4).

DEVICES

/dev/sua, /dev/sua-npi-cl, /dev/sua-npi-co, /dev/sua-tpi-cl, /dev/sua-tpi-co.

FILES

<ss7/sccpi.h>, <ss7/sua_ioctl.h>, <sys/npi.h>, <sys/npi_ss7.h>, <sys/npi_mtp.h>, <sys/npi_sccp.h>, <sys/tpi.h.h>, <sys/tpi_ss7.h>, <sys/tpi_mtp.h>, <sys/tpi_sccp.h>, <xti.h>, <xti_sccp.h>, <sys/socket.h>.

VERSIONS

The SUA driver is specific to the OpenSS7 stack. This is Version 2 of the interface.

REFERENCES

[1]: RFC 2960, Stream Control Transmission Protocol (SCTP), October 2000, Randall R. Stewart, ed., The Internet Society. (Obsoleted by RFC 4960) (Updated by RFC 3309) (Status: PROPOSED STANDARD) <http://www.ietf.org/rfc/rfc2960.txt>
[2]: NPI, Open Group CAE Specification: Network Provider Interface (NPI) Specification, Revision 2.0.0, Draft 2, August 17, 1992, (Parsippany, New Jersey), UNIXInternational,Inc., UNIX International Press. <http://www.openss7.org/docs/npi.pdf>
[3]: TPI Revision 2.0.0, Open Group CAE Specification: Transport Provider Interface (TPI) Specification, Revision 2.0.0, Draft 2, 1999, (Berkshire, UK), OpenGroup, Open Group Publication. <http://www.opengroup.org/onlinepubs/>
[4]: XTI/TLI Revision 1.0, Open Group CAE Specification: XOpen Transport Interface, Revision 1, n.d., (Berkshire, UK), XPG, X Programmer's Group. <http://www.opengroup.org/onlinepubs/>
[5]: XNS, Open Group CAE Specification: Technical Standard: Network Services (XNS), Issue 5.2, Draft 2, 1999, (Berkshire, UK), OpenGroup, Open Group Publication. [ISBN 1-85912-241-8] <http://www.opengroup.org/onlinepubs/>
[6]: RFC 3868, Signalling Connection Control Part User Adaptation Layer (SUA), October 2004, John Loughney, ed., The Internet Society. <http://www.ietf.org/rfc/rfc3868.txt>

TRADEMARKS

OpenSS7tm: is a trademark of OpenSS7 Corporation.
Linux®: is a registered trademark of Linus Torvalds.
UNIX®: is a registered trademark of The Open Group.
Solaris®: is a registered trademark of Sun Microsystems.

Other trademarks are the property of their respective owners.

IDENTIFICATION

The OpenSS7 Project: Package OpenSS7 version 0.9.2 released Mon, 15 Dec 2008 06:21:59 GMT.

This document was created by man2html, using the manual pages.
Time: 06:21:59 GMT, December 15, 2008