The division of network broadcasting addresses, how to calculate the network number and broadcasting

The following addresses do not belong to Network 100The host address is ( ).

When BCD does this kind of problem, you have to review the question first, you have to look at the IP address it gives, and then its mask is 20, that is, that is, its variable is 16, and then it is in the third bit.

It's actually a subnet in it.

This is actually a subnet (i.e., a subnet (i.e., the result obtained.

The CIDR blocks covered by the subnet are.

Among them are network addresses, which are not available.

is a broadcast address, which is also unavailable.

So the answer to d is obviously not right, in this kind of question sometimes we see some questions about the valid host address, and the answer it gives will even have, but in fact, this is a valid host address.

To synthesize this kind of topic, what we need to do is to do a good job of reviewing the topic, and then figure out the IP contained in each subnet.

As for (51) the network address is, then the broadcast address of the network is .

a． b．c． d．

This question is also very easy to do according to the above ideas.

According to the question, the mask is 26, ie.

The subnet is known.

The IP range contained in the subnet is:

is the network address.

that is, the broadcast address.

So the answer is C

This kind of topic doesn't have to be so complicated.

The following addresses do not belong to Network 100The host address for is ( )bcd

It's the same for the first 20 digits, and obviously d is not the same.

The address of the network is , then the broadcast address of the network is .

51）a． b．

Take advantage of IP149 88 . 160 .58 and the subnet mask can be used to calculate that the IP belongs to this network segment.

Let the host bit be 0, that is, you can know that the network number is.

Let the host bits be all 1, that is, the broadcast address can be known as .

The detailed process is as follows:

We divide this network address into subnets that can accommodate 101 54 2 hosts. Therefore, we need to determine the host bit first, then determine the network bit based on the host bit, and finally determine the detailed IP address.

1. Determine the host bit.

Arrange the number of hosts required from large to small: 101 54 2, and then determine the host bits of each subnet according to the number of IPs owned by the network: if the nth power of 2 - the number of IPs in the network segment is 2, then the host bits are equal to n.

So, get: 7 6 2.

2. Determine the network bit according to the host bit.

Subtract the host bit from 32 and the remaining value is the network bit, which gets: 25 26 30.

3. Determine the detailed IP address.

In binary, the number of bits in front of the IP is masked with the network bit value, followed by the IP bit. Select the first IP address of each subnet as the network address, the last IP address as the broadcast address, and the valid IP address in between. The network number is all 0 for the host bit, and the broadcast address is all 1 for the host bit.

A broadcast address is a special form of IP address, one is a direct broadcast address and the other is a limited broadcast address. The direct broadcast address contains a valid network number and a full "1" host number, as you said, 255 is a host fight lead number, 202 is a class C IP address, and class C IP address is what we often come into contact with.

A restricted broadcast address is a 32-bit all-1 IP address (. The restricted broadcast address is. This address is used as the destination address of the IP datagram during the host configuration process, at which point the host may not yet know the netmask of the network it is on, or even its IP address.

In no case should the router have a datagram whose destination address is a restricted broadcast address, and such a datagram only appears in the local network.

Network address: It is used to isolate the host address, and the area code is to isolate the ** number of different cities, and the network address can be used to plan and manage the host address in different environments, different fields, and different geographical environments. For example

This is the network address, and the host address under this network address is an independent network system.

Broadcast address: As the name suggests, it is to broadcast its own address information to all IP addresses on the network, and the broadcast is divided into intra-network broadcasting and network segment broadcasting, for example, this is your broadcasting address, broadcasting to all host addresses of this network, this is the broadcasting of the entire C-class network segment, this is a broadcast to the entire Internet, just like the ping of the win95 years can send broadcast packets, often forming an attack, because this response package is considerable!

The IP host bit is all 0

This is the network address.

All IP host bits are 1

This is the broadcast address.

In between is the host address.

Case-by-case analysis.

If you follow the main class network.

The last 24 bits of Class A are the host bits.

The last 16 bits of Class B are the host bits.

The last 8 bits of Class C are the host bits.

In the case of a subnet mask.

For example, the host is 8 bits.

The host address is.

The broadcast address is.

As long as a network address is used to identify a network, it does not refer to a specific host or device, but to identify a collection of hosts or network devices that belong to the same network. For example, the host number of a Class A address is the last 24 digits, so the network address is; The network address of the Class B address is the last 16 bits of the host number, and the network address is; The network address of a Class C address is;

An IP address specifies that a network address contains a valid network number and a host number with all "0s".

A broadcast is generated when a device sends data to all devices on the network.

Usually such an IP address ends with a full "1".

Divided into. Direct and limited broadcasting.