TCP/IP Implementation and Operations Guide

ClearPath MCP 21.0

June 2023

3787 7693-227

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Table of Contents

Overview
Documentation Updates
What's New?
Notation Conventions
Terminology Conventions
TCP/IP Architecture
Internet Protocol Version 6 (IPv6)
MCP Networking and IP Security (IPsec)
Summary of IPv6 Features
Migrating to IPv6
Key Differences Between IPv4 and IPv6
IPv6 Internet Standards (IETF RFCs)
TCP/IP Distributed Systems Services
Overview of TCP/IP Routing
TCP/IP Routing Commands
Dynamic DNS (DDNS)
IPv4 Addressing
Understanding IPv4 Address Classes
Dynamic Host Configuration Protocol (DHCP)
Classful Addressing Limitations
Subnetting
IPv6 Addressing
IPv6 Address Representation
IPv6 Address Type Identification
Unicast Addresses
Global Unicast Addresses
IPv6 Address Prefix Representation
IPv6 Alternative Representations of Addresses
Variable-Length Subnet Masking (VLSM)
Classless Interdomain Routing (CIDR)
CIDR in IPv4 Networks
CIDR in IPv6 Networks
TCP/IP IPv4 Network
TCP/IP IPv6 Network
Routing Information Protocol Version 2 (RIPv2)
IPv6 Neighbor Discovery
Support for Multiple Routes to a Destination
MCP Route States
Alternate Routes
Dead Gateway Detection (IPv4 Networks)
Discovering Unreachable Neighbors (IPv6 Networks)
Parallel Routes
Special Topologies
Multiple Assigned Default Routes
Multiple Local IP Addresses
Operating TCP/IP Software
Initializing the TCP/IP Network
U. S. Export Regulations Concerning IPv6 and IPsec
Dual Mode Initialization
IPv6 Initialization
Modifying the Autoconfiguration Setting
IP Security (IPsec) Initialization
SNMP Agent Initialization
Initializing TCP/IP
Terminating TCP/IP on the Enterprise Server Host
Inquiring on the Status of TCP/IP Software
Inquiring on the Status of IPsec
TCPIP Status Command Examples
Setting Timer Values
Setting the Routing Information Timer Value
Setting the LAN Resiliency Timer Value
Configuring Multiple Routes and Default Routes
Configuring Multiple Routes to a Remote Destination
Configuring Default IP Routes
Inquiring About Routing Problems
Clearing the Routing Table
Specifying Selection Criteria for Route Inquiries
Inquiring on the Routing Information Protocol (RIP)
Setting the Routing Information Protocol Authentication Type
IPv6 Default Address Selection
TCPIP Address Selection Policy
Inquiring on the Route Used to Reach a Remote Node
Modifying TCP/IP Components Online
Identifying a Local TCP/IP Host to the Network
Assigning IP Addresses to a Network Interface
Assigning Multiple Local IP Addresses and Mask Pairs to a Network Interface
Detecting a Duplicate IP Address on Your Network
Reporting on Autoconfigured Interfaces
Creating a Mapping Between a TCP/IP Host and One or More IP Addresses
Inquiring on One or More Host Names
Reaching a Remote Host or Other Network Interface on the Same Logical Host
Verifying That Packets Are Received by a Remote Host
Filtering TCP/IP Traffic
Filtering Frames Based on Port Numbers
Enabling Dynamic Port Filtering
Enabling Static Port Filtering
Filtering Broadcast Traffic
IPv6 Protocol Filtering
Deleting TCP/IP Components Online
Deleting an IP Route to a TCP/IP Host
Deleting Default IP Routes
Deleting a User-Specified Mapping (TCP/IP Host to IP Address)
Deleting All Learned Mappings
Deleting an Enterprise Server IP Address from the Network
Deleting Local IP Address and Mask Pairs
Enabling a Host to Use the Address Mask Protocol
Using Router Discovery
Enabling a Host to Use the Router Discovery Protocol
Using Neighbor Discovery
Specifying Neighbor Discovery Options
Setting the IPADDRESSLIST Attribute
Controlling TCP/IP End System Security
Differentiating Rules for Inbound/Outbound Dialogs and for TCP/UDP Protocols
Initialized Security Environment
Determining the Current TCP/IP End System Security State
Enabling or Disabling TCP/IP End System Security
Loading a Rules File
Changing to Another Rules File
Reviewing Security Rule Violations
Authorizing the Use of Well-Known TCPIP Ports
Using TCP/IP Options
Enabling and Disabling AllowPingFlood
Enabling and Disabling DHCP
Enabling and Disabling Dynamic DNS
Enabling and Disabling IP Security (IPsec)
Enabling and Disabling NoICMPInfo
Enabling and Disabling NoICMPTimeStamp
Enabling and Disabling SSH
Enabling and Disabling the AES-CBC Cipher Algorithm
Enabling and Disabling SSL
Enabling and Disabling SSL Version TLS 1.0
Enabling and Disabling TLS 1.0 Chained Certificates
Enabling and Disabling the SHA-1 Hash Algorithm
Configuring LAN Resiliency
Inquiring on the LAN Resiliency Timer
TCPIP LAN Resiliency Report
Disabling Mapping of Learned Host Names and IP Addresses
Enabling Use of RFC 1122 MTU
Enabling Use of RFC 2460 MTU
Enabling the Windows Server to Force the MTU to Acknowledge Every Two MTUs
Protecting TCP/IP Dialogs Against ICMP Attacks
Setting Path MTU Verification Interval
Enabling and Disabling Session Warnings
Specifying Autoconfiguration for a Network Interface
Obtaining an Autoconfigured IP Address Using the MAC Address
Specifying ICMPv6 Error Report Values
Specifying the Default Maximum Hop Limit for a Router
Closing Sockets by Job Number
Enabling and Disabling Default Keep Alive
Specifying and Inquiring on IP Multicast Frames
Updating an Initialization File to Use Multicast Addresses
Deriving Ethernet Multicast Addresses from Multicast IP Addresses
Enabling Multicast Address Handling for IPv4 Addresses Only
Preventing a Done Report From Being Sent
Specifying the Unsolicited Report Options for Multicast Listener Discovery
Specifying the Window Scale Factor
Specifying the TCP Selective Acknowledgement Option
Disabling and Enabling the Dynamic Initiation of Specified Port Numbers
Disabling the Dynamic Initiation of an Application
Enabling the Dynamic Initiation of an Application
Inquiring on the Dynamic Initiation Status of an Application
Monitoring TCP and UDP Port Events
Implementing Time-Wait for TCP/IP on MCP Systems
TCP Performance Considerations
LAN Speed
Frame Size
Message Size
Troubleshooting TCP/IP Installation and Configuration Problems
Verifying That TCP/IP End System Security Is Operable
Verifying that IP Security (IPsec) Is Operable
Inquiring About the TCP/IP Environment
Displaying Enterprise Server TCP/IP Reports
Monitoring TCP/IP System Activity with TCPIP DEBUG
Using the Trace Option of the TCPIP DEBUG Command
Using the Dump Option of the TCPIP DEBUG Command
Using the TCPIP DISPLAY, TCPIP DISPLAY INTERVAL, and TCPIP DISPLAY OPTIONS Commands
Using the TCPIP DISPLAY TABLE Command
Understanding the TCP/IP CONNECTION RESET Report Diagnostic Codes
Running OSI Applications over a TCP/IP Network
Functional Overview
Overview of the Implementation Process
Initializing the OSI Software on the TCP/IP Host
Identifying OSI Application Endpoints
Associating OSI and TCP/IP Addresses
Defining an NSAP Address Which Contains an Embedded IP Address
Configuring OSI-TCP/IP Address Pairs
Using the Operations Interface (OI) to Configure OSI-TCP/IP Address Pairs
Checking the OSI-TCP/IP Pairings Using Network Inquiries
Configuring a More Complex Network
Operating OSI Applications
TCP/IP Commands and Inquiries
Initialization File for the Sample Network
CNS Initialization File
TCP/IP Initialization File
BNA Initialization File
TCP/IP Capabilities
TCP/IP Capabilities - Network Services
TCP/IP Capabilities - Host Services
TCP/IP Port Numbers