Communications Server for z/OS V1R7 TCP/IP Implementation, Volume 1: Base Functions, Connectivity, and Routing

Chapter 1. Introduction 5

In CS for z/OS IP, two worlds converge, providing access to the z/OS UNIX environment and

the traditional MVS environment.

Figure 1-1 Functional overview

1.3.2 Operating environment

Since the z/OS UNIX environment is supported in the MVS environment there is no need to

discuss the creation of an MVS environment. However, there are some customization

requirements on the UNIX Systems Services side of the environment in order to start CS for

z/OS IP successfully. This dependence on UNIX, of course, implies that z/OS UNIX

administrators must also be familiar with both traditional MVS commands and interfaces.

Input/output flow process

Another feature of the operating environment illustrated in Figure 1-1 is the storage and

input/output designs. The operating environment design features a tightly integrated storage

and I/O model, known as CSM.

Communications Storage Management (CSM)

The CSM Facility is used by authorized programs to manage subsystem storage pools. It

provides a flat storage model that is accessible by multiple layers of the process model, as

Figure 1-1 illustrates. It is also accessible across z/OS address space boundaries, thereby

reducing the data moves between processes/tasks that exchange data as they perform work.

MPC+

SAMEHOST

(SNALINK,

X.25)

CDLC CLAW CTC HYPER LCS XCF ATM

TCP/IP Exclusive

DLCs

Shared DLCs

IP and ICMP Network Protocols and Interface Layer

TCP, UDP, and Raw Sockets Transport Protocol Layer

PFS

TN3270 Server, FTP server, FTP client,

SNMPv2 Agent, OE DPI library and OE SNMP

Command, OE Netstat, OE Ping, OE Tracerte,

OE RouteD, R-commands, RPC, Telnet

server, X-Windows client, DNS/WLM server

NDB, NICS, REXECD, RPC,

Kerberos, LPR client, MISC

server, NCPRoute, Portmapper,

NPF, SNMP query, X-Windows

client, DPI library

DNS server,

LPD server,

SMTP server,

Telnet client,

Ping,

Traceroute,

REXEC, RSH

IMS CICS

Pascal

API

C

S

M

C-Sockets

(asynch

only)

BPX

ASM

Callable

API

OE Sockets

LFS

Sockets Extended

Callable ASM, COBOL, PL/1

Assembler

C-Sockets

REXX

Sockets