Cisco mac address table reserved 48 spaces

This reduces the number of nodes per network, but you probably will still have more than enough.ДЇollowing are two main reasons for subnetting: With subnetting, you use bits from the node portion of the address to create more network addresses. This would give you a large number of possible node addresses, which in reality is probably not useful. Using this address and the default subnet mask, you could have a single network (150.150) and use the rest of the address as node addresses. To illustrate subnetting, for example, suppose that you have been assigned the Class B address 150.150.0.0. Subnetting is a process by which the node portions of an IP address create more networks than you would have if you used the default subnet mask. Now that you have looked at how IP addresses are used, you can learn the process of subnetting. You will likely see questions about address class and the corresponding default subnet mask. IPv4 Address Classes and the Number of Available Network/Host Addresses The exact numbers are provided in Table 3.2. Class C has an even larger number of networks, but each Class C address has an even smaller number of hosts. Class B has a larger number of networks, but each Class B address has a smaller number of hosts. The upshot of this system is that Class A has a small number of network addresses, but each Class A address has a large number of possible host addresses. A Class A address uses only the first octet to represent the network portion a Class B address uses two octets and a Class C address uses the first three octets. Of the three classes available for address assignments, each uses a fixed-length subnet mask to define the separation between the network and the node address. Class D is reserved for multicast addressing, and Class E is reserved for future development. The IPv4 address space has five address classes (A through E) although, only three (A, B, and C) assign addresses to clients. IP addresses are grouped into logical divisions called classes. Table 3.1 shows some examples of decimal-to-binary value conversions. If all the bits in the octet are 1, the value is 255, which is 128 + 64 + 32 + 16 + 8 + 4 + 2 + 1.Д«y using the set of 8 bits and manipulating the 1s and 0s, you can obtain any value between 0 and 255 for each octet. If all the bits are 0, the value of the octet is 0.

If the value is 1, it is counted as its decimal value, and if it is 0, it is ignored. The leftmost bit has a value of 128, followed by 64, 32, 16, 8, 4, 2, and 1, left to right.Д®ach bit in the octet can be either a 1 or a 0.

Each bit in each octet is assigned a decimal value. The result is that IP addresses contain 32 bits. IPv4ДЄn IPv4 address is composed of four sets of 8 binary bits, which are called octets. The discussion begins by looking at IPv4. IP addressing is different in IPv4 and IPv6. In IP addressing, another set of numbers, called a subnet mask, defines which portion of the IP address refers to the network address and which refers to the node address. All the devices on that network segment must then have different node addresses. ItвЂ™s a bit like a street name and house number in a personвЂ™s home address.Д®ach device on a logical network segment must have the same network address as all the other devices on the segment. In other words, the IP address provides two pieces of information. The address defines both the number of the network to which the device is attached and the number of the node on that network. To communicate on a network using TCP/IP, each system must be assigned a unique address. The following sections look at how IP addressing works for both IPv4 and the newest version of IP: IPv6. Fortunately, the Network+ exam requires only a fundamental knowledge of IP addressing. It can leave even the most seasoned network administrators scratching their heads. IP addressing is one of the most challenging aspects of TCP/IP.

A private network is any network to which access is restricted.

Class C addresses span from 192 to 223, with a default subnet mask of 255.255.255.0.

A Class A address uses only the first octet to represent the network portion, a Class B address uses two octets, and a Class C address uses three octets.

What are the reserved IPv4 ranges for private networks?.

What is the range that Class C addresses span in the first octet?.

How many octets does a Class A address use to represent the network portion?.

If you can correctly answer these questions before going through this section, save time by skimming the Exam Alerts in this section and then complete the Cram Quiz at the end of the section.

Cisco mac address table reserved 48 spaces