Which subnet mask

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Please contact us. We just sent you an email to confirm your email address. Once you confirm your address, you will begin to receive the newsletter. Subnet Mask. A subnet mask of Definitions by TechTerms. Some cover a wider range of functions and have greater scope, while others have specific utilities.

These tools may provide information such as IP range, IP address, subnet mask, and network address. In this situation, the IP address is followed by the number of bits in the mask. For example:. Blog Contact Support. Request a Demo. Subnet Mask Definition Every device has an IP address with two pieces: the client or host address and the server or network address.

IP Address Classes and Subnet Masks Since the internet must accommodate networks of all sizes, an addressing scheme for a range of networks exists based on how the octets in an IP address are broken down. How Does Subnetting Work? What Is a Subnet Mask Calculator? Use a HEX Subnet Calculator to calculate the first and last subnet addresses, including the hexadecimal notations of multicast addresses.

A simple IP Subnet Mask Calculator determines the smallest available corresponding subnet and subnet mask. For example: Featured Resources White Papers. Learn about how Avi's elastic container services integrate with Kubernetes clusters. View Now. It's then the responsibility of the router to forward the packet to the correct subnet. Incorrect Subnet Mask: If a network uses a subnet mask other than the default mask for its address class, and a client is still configured with the default subnet mask for the address class, communication will fail to some nearby networks but not to distant ones.

As an example, if you create four subnets such as in the subnetting example but use the incorrect subnet mask of In this situation, packets destined for hosts on different physical networks that are part of the same Class C address won't be sent to a default gateway for delivery.

A common symptom of this issue is when a computer can communicate with hosts that are on its local network and can talk to all remote networks except those networks that are nearby and have the same class A, B, or C address.

Incorrect IP Address: If you put computers with IP addresses that should be on separate subnets on a local network with each other, they won't be able to communicate. They'll try to send packets to each other through a router that can't forward them correctly.

A symptom of this problem is a computer that can talk to hosts on remote networks, but can't communicate with some or all computers on their local network. To correct this problem, make sure all computers on the same physical network have IP addresses on the same IP subnet. If you run out of IP addresses on a single network segment, there are solutions that go beyond the scope of this article. Incorrect Default Gateway: A computer configured with an incorrect default gateway can communicate with hosts on its own network segment.

But it will fail to communicate with hosts on some or all remote networks. A host can communicate with some remote networks but not others if the following conditions are true:. Internet--The global collection of networks that are connected together and share a common range of IP addresses.

Network--There are two uses of the term network in this article. One is a group of computers on a single physical network segment. The other is an IP network address range that is allocated by a system administrator. Octet--An 8-bit number, 4 of which comprise a bit IP address. They have a range of that correspond to the decimal values Wide area network WAN --A large network that is a collection of smaller networks separated by routers.

The Internet is an example of a large WAN. Feedback will be sent to Microsoft: By pressing the submit button, your feedback will be used to improve Microsoft products and services. Privacy policy. Skip to main content. This browser is no longer supported. Download Microsoft Edge More info. Contents Exit focus mode. Lining up the IP address and the subnet mask together, the network, and host portions of the address can be separated: It gives you the following addresses: Some other common subnet masks are: Decimal Binary Following are the ranges of Class A, B, and C Internet addresses, each with an example address: Class A networks use a default subnet mask of In some scenarios, the default subnet mask values don't fit the organization needs for one of the following reasons: The physical topology of the network The numbers of networks or hosts don't fit within the default subnet mask restrictions.

The next section explains how networks can be divided using subnet masks. These four networks would have as valid host addresses: A host can communicate with some remote networks but not others if the following conditions are true: A single physical network has more than one router. The wrong router is configured as a default gateway. Glossary Broadcast address--An IP address with a host portion that is all ones. Network address--An IP address with a host portion that is all zeros. Router--A device that passes network traffic between different IP networks.

Subnet Mask--A bit number used to distinguish the network and host portions of an IP address. Subnet or Subnetwork--A smaller network created by dividing a larger network into equal parts.