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Questions tagged [subnet]

A subnetwork, or subnet, is a logically visible subdivision of an IP network.

A subnet is a logical grouping of connected network devices. Nodes on a subnet tend to be located in close physical proximity to each other on a LAN.

All computers that belong to a subnet are addressed with a common, identical, most-significant bit-group in their IP address. This results in the logical division of an IP address into two fields, a network or routing prefix and the rest field or host identifier. The rest field is an identifier for a specific host or network interface.

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What is the difference between a VLAN and a subnet?

I have read numerous forums and articles regarding VLANs and subnets. However, I haven't understood the functions of each apart from the following: Subnets allow the segmentation of a network VLANs are an isolated portion of a…
PeanutsMonkey
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Why are subnet-masks relevant for the individual computer on the network?

I understand how subnet-masks are used to divide a network into sub-networks, but, why does every computer in the network need to know the subnet-mask and not just the router? I could understand it, if each computer were physically connected to…
Orpedo
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What is a subnet mask, and the difference between a subnet mask of 255.255.255.0 and 255.0.0.0?

My DSL/WiFi router provided by my ISP has an internal IP address of 10.0.0.138, the addresses provided by DHCP are in the format of 10.0.0.xxx. Now, I want to start using static IP addresses on my local network, and I don't know what to provide for…
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Why do we need subnet mask?

Since a IPv4 address already gives the information of the network and and host, why do we still need a subnet mask? The 1st Octet already specify the network class (1-127: A, 128-191: B, 192-223: C etc.). A, B, or C implies the number of octets for…
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What does it mean to have a subnet mask /32?

I see in this question, the routing table has: 192.168.1.1/32 link#4 UCS 2 0 en0 openwrt.lan 46:94:fc:63:fc:7 UHLWIir 11 3610 en0 1200 192.168.1.125/32 link#4 UCS …
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Why isn't 255.255.249.0 a valid subnet mask?

I was just wondering about this question above and I would greatly appreciate it if someone can explain why 255.255.249.0 isn't a valid subnet mask.
bobby
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Are subnets always contiguous 1s?

I understand the basic premise behind subnet masks, such as 255.255.255.0. But all the subnet examples I’ve seen have been (from left-to-right) contiguous 1s (HI bits). For instance, 255.255.0.0 (/16) translates to the following octets: 11111111 .…
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What is the difference between a subnet mask and a netmask?

Is there any logic in using two different names for determining host ID and net ID? For example, if you type print route in a Command Prompt you get things with netmask, but the IPv4 settings seems to use subnet mask. Is there any significant…
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Why is my subnet mask 255.255.255.255?

I have a modem which used for internet broadband and I got an IP address in the 'A' class 10.x.x.x and have netmask 255.255.255.255. What does 255.255.255.255 mean exactly? When I try to sniff with promisc mode, will this 'netmask' never allow me…
capede
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Communicating with devices on a different subnet

Let me start this off by saying that I am very new to how IP Address / Subnet Addresses work, and networking in general. This stuff is generally mystifying, and I've had a hard time understanding what I've read so far. I have a network device that…
nathan lachenmyer
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Is there any reason to subnet a home network?

For networks I understand we set a netmask on each computer to let it know what IPs it can talk to without going through the router - IPs on the same subnet can talk directly to each other and do not have to go through a router/switch. However, in…
Will
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How to create a separate subnet for wireless access?

I need to configure my wireless router so all wireless devices are on a different subnet (192.168.2.1). The wireless devices should be able to access the internet, but ideally not the workstations on the LAN. Here is my network: All suggestions…
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What are the essentials of a Subnet mask?

What is the use of a subnet mask? What is the below output conveying to the user? Connection-specific DNS Suffix . : IP Address. . . . . . . . . . . . : 192.168.1.2 Subnet Mask . . . . . . . . . . . : 255.255.255.0 Default Gateway . . . . . . .…
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What does (Preferred), (Tentative) and (Duplicate) mean against an IPv4 Address with ipconfig

I have been tinkering with subnets and have noticed the above as annotations to the IPv4 line of ipconfig. IPv4 Address. . . . . . . . . . . : 192.168.1.241(Tentative) IPv4 Address. . . . . . . . . . . : 192.168.1.8(Preferred) What do they mean?
OldCurmudgeon
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Why is ip address listed as 172.18.0.150/24?

Why is IP Address listed with this notation 172.18.0.150/24? I mean the ip is 172.18.0.150 only why it haves /24?, and then whatever what subnet that is on should be someone else's worries, no? 3: eth0: mtu 1500…
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