HP-UX HB v13.00 Ch-09 - Networking Basics

HP-UX Handbook – Rev 13.00 Page 8 (of 27)
Chapter 09 Network Basics
October 29, 2013
in decimal: 15.140.15.255
IPv6
IPv6 is the next generation network-layer protocol designed to be the successor to the current
Internet Protocol version 4 (IPv4). It provides the packet delivery service for TCP, UDP and
ICMPv6.
IPv6 has significant advantages over IPv4 in terms of increased address space, simplified header
format, integrated QoS support and mandatory security.
IPv6 has extended the address size from 32 bits to 128 bits and they are textually represented in
hex-colon notation as x:x:x:x:x:x:x:x, where the x's are the hexadecimal values of the eight 16-
bit pieces of the address. For example fedc:83ff:fef6:417a:210:83ff:fef6:3dc0.
Private IP Addresses
If someone needs to build a network with private IP-addresses, with no connection to the
Internet/WAN, it is still recommended that the IP-addresses follow the RFC 1918 standard.
The following address ranges are exclusively used for private networks and never for the
Internet.
Class A: 10.0.0.0 ...10.255.255.255
Class B: 172.16.0.0 ...172.31.255.255
Class C: 192.168.0.0 ...192.168.255.255
Routing
When we discuss routing, we have to differentiate between two aspects:
How does the Operating System find out, which network interface has to be used?
How does the information find its path (from source to destination) through the different
subnets?
The following information will cover the first question only.
Note: Always disable gated, arpd or similar programs, if you do not know exactly that they are
really needed and how to configure those programs!
You need to be familiar with the following terms, if you would like to understand routing:
Loopback Interface: virtual interface to allow locally running processes to communicate using
networking methods without using any real network hardware.
Host Route: route, giving the direction to a single host
Network Route: route, giving the direction to a network
Default Route: the way to any other (not explicit listed) system or network. The default keyword
indicates a wildcard route, used as a last resort if no route is specified for a particular remote host