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Oracle Solaris Administration: IP Services     Oracle Solaris 10 1/13 Information Library
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Document Information

Preface

Part I Introducing System Administration: IP Services

1.  Oracle Solaris TCP/IP Protocol Suite (Overview)

Part II TCP/IP Administration

2.  Planning Your TCP/IP Network (Tasks)

3.  Introducing IPv6 (Overview)

4.  Planning an IPv6 Network (Tasks)

5.  Configuring TCP/IP Network Services and IPv4 Addressing (Tasks)

6.  Administering Network Interfaces (Tasks)

7.  Configuring an IPv6 Network (Tasks)

8.  Administering a TCP/IP Network (Tasks)

9.  Troubleshooting Network Problems (Tasks)

10.  TCP/IP and IPv4 in Depth (Reference)

What's New in TCP/IP and IPv4 in Depth

TCP/IP Configuration Files

/etc/hostname.interface File

/etc/nodename File

/etc/defaultdomain File

/etc/defaultrouter File

hosts Database

/etc/inet/hosts File Format

Initial /etc/inet/hosts File

How Name Services Affect the hosts Database

ipnodes Database

netmasks Database

What Is Subnetting?

Creating the Network Mask for IPv4 Addresses

/etc/inet/netmasks File

inetd Internet Services Daemon

Network Databases and the nsswitch.conf File

How Name Services Affect Network Databases

nsswitch.conf File

Changing nsswitch.conf

bootparams Database

Wildcard Entry for bootparams

ethers Database

Other Network Databases

networks database

protocols Database

services Database

Routing Protocols in Oracle Solaris

Routing Information Protocol (RIP)

ICMP Router Discovery (RDISC) Protocol

Network Classes

Class A Network Numbers

Class B Network Numbers

Class C Network Numbers

11.  IPv6 in Depth (Reference)

Part III DHCP

12.  About DHCP (Overview)

13.  Planning for DHCP Service (Tasks)

14.  Configuring the DHCP Service (Tasks)

15.  Administering DHCP (Tasks)

16.  Configuring and Administering the DHCP Client

17.  Troubleshooting DHCP (Reference)

18.  DHCP Commands and Files (Reference)

Part IV IP Security

19.  IP Security Architecture (Overview)

20.  Configuring IPsec (Tasks)

21.  IP Security Architecture (Reference)

22.  Internet Key Exchange (Overview)

23.  Configuring IKE (Tasks)

24.  Internet Key Exchange (Reference)

25.  IP Filter in Oracle Solaris (Overview)

26.  IP Filter (Tasks)

Part V IPMP

27.  Introducing IPMP (Overview)

28.  Administering IPMP (Tasks)

Part VI IP Quality of Service (IPQoS)

29.  Introducing IPQoS (Overview)

30.  Planning for an IPQoS-Enabled Network (Tasks)

31.  Creating the IPQoS Configuration File (Tasks)

32.  Starting and Maintaining IPQoS (Tasks)

33.  Using Flow Accounting and Statistics Gathering (Tasks)

34.  IPQoS in Detail (Reference)

Glossary

Index

Network Classes


Note - Class-based network numbers are no longer available from the IANA, though many older networks are still class-based.


This section provides details about IPv4 network classes. Each class uses the 32-bit IPv4 address space differently, providing more or fewer bits for the network part of the address. These classes are class A, class B, and class C.

Class A Network Numbers

A class A network number uses the first 8 bits of the IPv4 address as its “network part.” The remaining 24 bits contain the host part of the IPv4 address, as the following figure illustrates.

Figure 10-3 Byte Assignment in a Class A Address

image:Diagram shows bits 0-7 is network part and remaining 24 bits are host part of a 32 bit IPv4 Class A address.

The values that are assigned to the first byte of class A network numbers fall within the range 0–127. Consider the IPv4 address 75.4.10.4. The value 75 in the first byte indicates that the host is on a class A network. The remaining bytes, 4.10.4, establish the host address. Only the first byte of a class A number is registered with the IANA. Use of the remaining three bytes is left to the discretion of the owner of the network number. Only 127 class A networks exist. Each one of these numbers can accommodate a maximum of 16,777,214 hosts.

Class B Network Numbers

A class B network number uses 16 bits for the network number and 16 bits for host numbers. The first byte of a class B network number is in the range 128–191. In the number 172.16.50.56, the first two bytes, 172.16, are registered with the IANA, and compose the network address. The last two bytes, 50.56, contain the host address, and are assigned at the discretion of the owner of the network number. The following figure graphically illustrates a class B address.

Figure 10-4 Byte Assignment in a Class B Address

image:Diagram shows bits 0-15 is network part and remaining 16 bits are host part of a 32 bit IPv4 Class B address.

Class B is typically assigned to organizations with many hosts on their networks.

Class C Network Numbers

Class C network numbers use 24 bits for the network number and 8 bits for host numbers. Class C network numbers are appropriate for networks with few hosts – the maximum being 254. A class C network number occupies the first three bytes of an IPv4 address. Only the fourth byte is assigned at the discretion of the network owners. The following figure graphically represents the bytes in a class C address.

Figure 10-5 Byte Assignment in a Class C Address

image:Diagram shows bits 0-23 is network part and remaining 8 bits are host part of a 32 bit IPv4 Class C address.

The first byte of a class C network number covers the range 192–223. The second and third bytes each cover the range 1– 255. A typical class C address might be 192.168.2.5. The first three bytes, 192.168.2, form the network number. The final byte in this example, 5, is the host number.