.TH ISO 4F "9 December 1988"
.ds ]W Wisconsin ARGO 1.0
.UC  4
.SH NAME
iso \- ISO protocol family
.SH SYNOPSIS
.B #include <sys/types.h>
.br
.B #include <netargo/iso.h>
.SH DESCRIPTION
The ISO protocol family is a collection of protocols
that uses the ISO address format.
The ISO family provides protocol support for the
SOCK_SEQPACKET abstraction through the TP protocol (ISO 8073), 
and for the SOCK_RAW abstraction
by providing direct access (for debugging) to the
CLNP (ISO 8473) network layer protocol.
.SH ADDRESSING
ISO addresses are based upon ISO 8348/AD2, 
"Addendum to the Network Service Definition Covering Network Layer Addressing."
.PP
Sockets bound to the OSI protocol family use
the following address structure:
.sp 1
.nf
._f
struct sockaddr_iso {
	short	siso_family;
	u_short	siso_tsuffix;
	struct	iso_addr siso_addr;
};
.sp 1
.fi
.PP
This fields of this structure are:
.TP 10
\fIsiso_family:\fR
Identifies the domain: AF_ISO or AF_INET.
.TP 10
\fIsiso_tsuffix:\fR
The transport part of the address, described below.
.TP 10
\fIsiso_addr:\fR
The network part of the address, described below.
.SS TRANSPORT ADDRESSING
.PP
The above structure describes a simple form of 
ISO \fItransport\fR addresses.
An ISO transport address is similar to an Internet address in that
it contains a network-address portion and a portion that the
transport layer uses to multiplex its services among clients.
In the Internet domain, this portion of the address is called a \fIport\fR.
In the ISO domain, this is called a \fItransport selector\fR
(also known at one time as a \fItransport suffix\fR).
While ports are always 16 bits, 
transport selectors may be
of (almost) arbitrary size.
ARGO supports two forms of transport selectors:
"normal" or 16-bit selectors, and
"extended" selectors, or selectors that may be from 1-64 bytes
in length.
The default mode of operation is to use 16-bit transport selectors.
These addresses can be represented with the above structure.
When transport selectors of any other size are used, the transport
selector is kept in a separate structure.
See the manual page \fItp(4p)\fR.
.SS NETWORK ADDRESSING
.PP
ISO network addresses are limited to 20 bytes in length.
ISO network addresses can take any format.
ARGO 1.0 supports three formats.
See \fIisodir(3)\fR and \fIisodir(5)\fR.
.SH PROTOCOLS
The ARGO 1.0 implementation of the 
ISO protocol family comprises
the Connectionless-Mode Network Protocol (CLNP), 
and the Transport Protocol (TP), classes 4 and 0,
and X.25.
TP is used to support the SOCK_SEQPACKET
abstraction.
A raw interface to CLNP is available
by creating an ISO socket of type SOCK_RAW.
This is used for CLNP debugging only.
.SH SEE ALSO
tp(4P), cons(4p), clnp(4P), isodir(3), iso(4f), isodir(5),
"The ARGO 1.0 Kernel Programmer's Guide",
"Installing ARGO 1.0 on Academic Operating Systems 4.3 Release 2"