Syngress - Eleventh Hour Network+ Exam N10-004 Study Guide (11 ...

92 CHAPTER 6 TCP/IP and Routing
For example, the binary value of 00101001 would be translated to: 32 + 8 +
1 = 41.
Network ID and Host ID
A 32-bit IP address is subdivided into two portions, the network address (shared
by all computers on that network) and the host address. See Figure 6.1 for
an example of the division between the network and the host address. When
combined, the result is a single unique IP address on the network.
Crunch Time
Be sure that you know these facts related to network
addresses:
■ All the hosts on the same network segment must
have the same network ID.
■ Primary network IDs are managed by the Internet
Network Information Center (InterNIC).
■ Network addresses are broken into classes: Class
A, B, C, D, and E.
■ Classes A, B, and C are used for standard
addressing.
■ Class D is reserved for IP multicast addresses.
■ Class E addresses are reserved for future use,
and the class is considered experimental.
■ A new classless (also called variable length subnet
masking [VLSM]) system now exists. The classbased
system now often is referred to as classful.
■ We can identify the number of bits used for the
network by notating how many total bits (counting
from left to right) are used in the network
address.
Network ID and Host ID
Segment 1: 225.32.16._ 5 Network ID.__.__.__.1 5 Host ID
Segment 2: 225.32.18._ 5 Network ID.__.__.__.1 5 Host ID
225.32.16.2_
225.32.16.4_
Ethernet Network ID 225.32.16.z
225.32.16.1_
Router
225.32.18.1
Ethernet Network ID 225.32.18.z
225.32.18.3_
FIGURE 6.1
Network and host IDs
225.32.16.3_
Computers on the same network must
have the same Network ID and
different Host ID.
225.32.18.2_