ISO(4F)

NAME
iso - ISO protocol family

SYNOPSIS
#include <sys/types.h>
#include <netargo/iso.h>

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.

ADDRESSING
ISO addresses are based upon ISO 8348/AD2, "Addendum to the Network Service Definition Covering Network Layer Addressing."

Sockets bound to the OSI protocol family use the following address structure:

struct sockaddr_iso {
	short	siso_family;
	u_short	siso_tsuffix;
	struct	iso_addr siso_addr;
};

This fields of this structure are:

siso_family:
    Identifies the domain: AF_ISO or AF_INET.

siso_tsuffix:
    The transport part of the address, described below.

siso_addr:
    The network part of the address, described below.

  TRANSPORT ADDRESSING

The above structure describes a simple form of ISO transport 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 port. In the ISO domain, this is called a transport selector (also known at one time as a transport suffix). 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 tp(4p).

  NETWORK ADDRESSING

ISO network addresses are limited to 20 bytes in length. ISO network addresses can take any format. ARGO 1.0 supports three formats. See isodir(3) and isodir(5).

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.

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"