Introduction to z/OS Basics
Chapter 19: Networking on z/OS
© 2006 IBM Corporation
Chapter 19 Networking
Objectives
 In this chapter, you will learn:
– An overview of the communication network model layers
– The software components of the z/OS Communications
Server product
– The difference between a VTAM subarea and APPN
network topology
– How the IP network can be used to transport data
between SNA applications.
– Commonly used TCP/IP and VTAM commands
2
© 2006 IBM Corporation
Chapter 19 Networking
IBM Communications Server
z/OS
Applications
Applications
Applications
RPC
APPC
TCP/IP
Sockets
3
SNA
APPC
Sockets
RPC
© 2006 IBM Corporation
Chapter 19 Networking
Open Systems Interconnect (OSI) network model
Layered Network Models
TCP/IP
OSI
SNA
Applications
Transaction Services
Presentation
NAU Services Mgr
Func. Mgmt Data Srvc
Session
Data Flow Control
TCP UDP
Transport
Transmission Control
IP ARP RARP ICMP
Network
Path Control
Data Link
Data Link
Data Link Control
Physical
Physical
Physical
telnet, np, SNMP, SMTP
4
© 2006 IBM Corporation
Chapter 19 Networking
TCP/IP introduction
xSeries
Router
Network A
Network B
zSeries
Gateway
pSeries
Router
zSeries
xSeries
Router
xSeries
Gateway
Workstation
5
pSeries
Workstation
Workstation
© 2006 IBM Corporation
Chapter 19 Networking
Interconnecting TCP/IP networks
Router
Gateway
Router
Router
Bridge
Gateway
Network A
Network B
INTER-NETWORK
6
© 2006 IBM Corporation
Chapter 19 Networking
Internet addressing
Host B
Gateway
IPv4
IP Address
193.15.6.4
Host A
Network
131.12
IP Address
131.12.8.2
7
Host C
IP Address
131.12.8.1
131.12
8.2
network ID
host
address
Network
193.15.6
IP address = x.x.x.x (32 bits)
= <net-ID> <host addr>
Class A = <x> <x.x.x>
Class B = <x.x> <x.x>
Class C = <x.x.x> <x>
IP Address
193.15.6.3
193.15.6
3
network ID
host
address
© 2006 IBM Corporation
Chapter 19 Networking
TCP/IP commands
 TCP/IP Commands can be entered
– TSO ready prompt
– ISPF Command Shell
– Prefixing the command with TSO on any ISPF command line.
•
•
•
•
•
•
NETSTAT
PING
TRACERTE
NSLOOKUP
TELNET
FTP
– z/OS UNIX shell prompt (prefix “o”=command)
• onetstat
8
© 2006 IBM Corporation
Chapter 19 Networking
VTAM overview - the SNA environment
pSeries
Host processor
PC
317x
Cluster
controller
z/OS
CICS
VTAM
Windows
AIX
zSeries
iSeries
zSeries
z/VM
OS/400
Communication
controller (37xx)
NCP
Workstations
9
© 2006 IBM Corporation
Chapter 19 Networking
A pure VTAM subarea network
VTAM (SSCP) Subarea Configuration
VTAM subarea (2)
SSCP (PU Type 5)
LU (CICSTS2)
LU (IM S2)
VTAM subarea (1)
SSCP (PU Type 5)
LU (CICSTS1)
LU (IM S1)
NCP subarea (11)
PU Type 4
LU
PU Type 2
LU
New York City
Chicago
Los Angeles
LU
LU
PU Type 2
NCP subarea (12)
PU Type 4
NCP subarea (13)
PU Type 4
PU Type 2
VTAM subarea (3)
SSCP (PU Type 5)
LU (CICSTS3)
LU (IM S3)
10
LU
LU
PU Type 2
LU
LU
© 2006 IBM Corporation
Chapter 19 Networking
APPN topology
VTAM (CP) APPN Configuration
VTAM APPN
CP (PU Type 5)
LU (CICSTS1)
LU (IM S1)
OSA
HPR/IP
VTAM APPN
CP (PU Type 5)
LU (CICSTS2)
LU (IM S2)
OSA
HPR/IP
router
PC
Internet
segment
PC
New York City
Los Angeles
PC
Internet
and /or
intranet
Chicago
PC
router
router
internet
segment
Internet
segment
OSA
HPR/IP
VTAM APPN
CP (PU Type 5)
LU (CICSTS3)
LU (IM S3)
11
PC
PC
PC
PC
© 2006 IBM Corporation
Chapter 19 Networking
Common VTAM commands
 D NET,VTAMOPTS Displays VTAM startup options.
 D NET,CSM[,OWNERID=ALL] Displays communication storage usage.
 D NET,APPLS Displays status of defined applications (ACBs).
 D NET,MAJNODES Displays status of VTAM activated ATCCONxx members.
 D NET,TOPO,LIST=SUMMARY Displays APPN topology information.
 D NET,CPCP Displays status of APPN CP-CP sessions.
 D NET,SESSIONS Displays status of subarea SSCP-SSCP sessions.
 D NET,CDRMS Displays status of subarea cross domain resource
managers.
 D NET,EXIT Displays status of VTAM exit points.
12
© 2006 IBM Corporation
Chapter 19 Networking
Summary
 In this chapter, you have learned:
– An overview of the communication network model layers
– Software components of the z/OS Communications
Server product
– The difference between a VTAM subarea and APPN
network topology
– How the IP network can be used to transport data
between SNA applications.
– Commonly used TCP/IP and VTAM commands
13
© 2006 IBM Corporation
Introduction to z/OS Basics
Backup slides
Instructor slides with additional material
© 2006 IBM Corporation
Chapter 19 Networking
SDLC / CICS
15
© 2006 IBM Corporation