3Com 10014298 manual Configuring IP, Address

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NETWORK PROTOCOL OPERATION

	This chapter covers the following topics:
	■	Configuring IP Address
	■ Configuring Address Resolution Protocol (ARP)
	■	DHCP Relay
	■	IP Performance
Configuring IP	IP address is a 32-bit address represented by four octets. IP addresses are divided
Address	into five classes, A, B, C, D and E. The octets are set according to the first few bits

of the first octet.

The rule for IP address classification is described as follows:

■ Class A addresses are identified with the first bit of the first octet being 0. ■ Class B addresses are identified with the first bits of the first octet being 10.

■ Class C addresses are identified with the first bits of the first octet being 110. ■ Class D addresses are identified with the first bits of the first octet being 1110. ■ Class E addresses are identified with the first bits of the first octet being 11110.

Addresses of Classes A, B and C are unicast addresses. The Class D addresses are multicast addresses and Class E addresses are reserved for future use.

At present, IP addresses are mostly Class A, Class B and Class C. IP addresses of Classes A, B and C are composed of two parts, network ID and host ID. Their network ID lengths are different.

■ Class A IP addresses use only the first octet to indicate the network ID. ■ Class B IP addresses use the first two octets to indicate the network ID. ■ Class C IP addresses use the first three octets to indicate the network ID.

At most, there are: 28 =128 Class A addresses, 216=16384 Class B addresses and 224=2,097,152 Class C addresses.

The IP address is in dotted decimal format. Each IP address contains 4 integers in dotted decimal notation. Each integer corresponds to one byte, e.g.,10.110.50.101.

Configuring an IP Address is described in the following sections:

■Subnet and Mask

■Configuring an IP Address