Sun Microsystems StorageTek StreamLine SL8500, System Assurance Manual

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TCP/IP Connectivity
188 SL8500: Systems Assurance Guide • July 2011 E24254-01
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Network Addressing
To communicate on a network, each device must have a unique number or
“address.”
An Internet Protocol or IP address is a unique number that identifies a device
and allows it to communicate on a network. All other IP network devices—
including computers, routers, and libraries—must have its own unique
address. IP addresses are usually represented by a dotted decimal notation of
four numbers from 0 to 255.
For example: 128.80.142.23 is an IP address.
An IP address has two components, the network address and the host
address. Assuming this is a Class B network,
• the first two numbers (128.80) represent the network address
• the second two numbers (142.23) identify a particular host or device on
this network.
There are five classes of IP ranges: Class A, Class B, Class C, Class D, and
Class E—while only A, B and C are commonly used. Each class allows for a
range of valid IP addresses. Below is a listing of these addresses.
Table 92. Network IP Classes and Address Ranges
Class Address Range Supports
Class A 1.0.0.1 to
126.255.255.254 Supports 16 million hosts on each of 127 networks.
Class B 128.1.0.1 to
191.255.255.254 Supports 65,000 hosts on each of 16,000 networks.
Class C 192.0.1.1 to
223.255.254.254 Supports 254 hosts on each of 2 million networks.
Class D 224.0.0.0 to
239.255.255.255 Reserved for multicast groups.
Class E 240.0.0.0 to
254.255.255.254 Reserved.