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

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Why subnet mask for IP 10.0.1.4 is 255.255.255.0?

Well I'm not sure whether I'm missing something here. But all I've read is that if first octet of IP is within 0 - 127 then it is categorized as Class A subnet and correspondingly Subnet Mask for ...
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Creating a DMZ with two routers

Hopefully it's okay to post semi-"I am learning" questions on this forum! Basically, I have two routers (both Netgear D834G's) and would like to setup a DMZ at home (merely for learning purposes and ...
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Routing to one IP via different gateways

I have an OpenVPN connection (point to point). When program connects to server it gets IP and Gateway dynamically, from server. I need to make windows add route to my secure server through given ...
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Do machines connected to the same switch belong to the same subnet?

When we talk about a subnet - do we mean all the systems connected to the same switch? If I have an assigned IP address of 10.0.2.1, am I in the same subnet as that of 10.0.1.39? When we talk about ...
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Ping a PC connected through crossover cable to one connected to router

I want to ping (technically, i need to connect to port 80) a PC that is connected to a second PC (through crossover cable), that's connected to a Router. I have a little sketch of what I'm trying to ...
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318 views

Viewing computers connected to my ISP

If there are many computers connected to my ISP then doesn't that mean they are all on the same network? If so, I should be able to see them. Why is it that this does not happen? The question Other ...
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Packet sent to the default gateway addressed to the same subnet. What happens?

Just a theoretical question (out of curiosity). If a host sent a packet to its default gateway and the packet has a destination address within the IP range of the subnet, what should the gateway do in ...
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using a gateway outside your subnet but on the same switch, with no router

I have set up a network in a non-standard way, and would like to know if what I did is technically correct, or if I just got lucky. The setup works fine with my $20 5-port Linksys switch, but not ...
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I have just created a subnet for a local network, connecting to a standalone server on another network, now I cannot connect to the internet

I am just learning some new aspects of servers and networking. We have a network of 5 subnets that all interconnect with each-other. In order to get two computers on the subnet that we were setting ...
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Many hosts sharing network ID = slow network?

From Networking all in one For Dummies: "The second reason for subnetting is that even if a single organization has thousands of network devices, operating all those devices with the same network ID ...
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1answer
831 views

Two subnets on one switch with no VLAN and possible problems

As far as I know in order to use two subnets on one physical cable VLAN's are recommended. However, is it possible to achieve this (i.e: two subnets on one physical network) like 192.168.1.0/24 and ...
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How does CIDR slow the exhaustion of IPv4?

In the Wikipedia article on CIDR, it says The Internet Engineering Task Force introduced CIDR in 1993 to replace the previous addressing architecture of classful network design in the ...
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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 ...
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Where are addresses from the network 0.0.0.0/8 used in practice?

I read that this pool: Means "these hosts" in "this network" Is used for self-identification Is used for broadcast messages My questions are: Where exactly these addresses can be found? Which ...
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Internet issues with subnet mask/DNS?

I woke up today to find that my internet wasn't working. I checked all the cables, and everything was connected, I tried to connect to my router @ 192.168.1.1 . It didn't connect. I checked the cables ...
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542 views

iPhone can't connect to internet on other subnet, but other computers can

Here's my setup; I'm a router newb so I don't completely understand the intricacies of my configuration - but suffice it to say, I've set it up this way so that anyone who's connected to Router A ...
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1answer
209 views

Calculating Subnets

I have just set up my first home LAN, and I want to start playing around with some basic networking concepts. Specifically, I would like to create two subnets. Now although I want these subnets to be ...
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How can I share my internet connection using a router?

How can I share my internet connection using a router? I get 192.168.1.150 from my provider and 192.168.1.1 as a DNS server, mask is 255.255.255.0 I suppose 150 is my gateway now. What IP should ...
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how to force an illegal netmask in ubuntu

I want to force a netmask on my Ubuntu machine. For example, I want 11.0.0.1 to get a netmask of 255.255.255.0 I tried editing /etc/network/interfaces and I forced the desired netmask, but as soon as ...
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What is the difference between a VLAN and a subnet? [closed]

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 ...
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Network printer connection issues with different subnet on Win 7 Pro?

So we have a mixed node set on our network with Win XP Pro, Win 7 Pro, Ubuntu 11.04, Win 2k3 Server Std, etc all within in an Active Directory Environment. We also have network printers that are ...
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Chaining subnet fails

Is it possible to do the following: Machine1 Kubuntu 8.04 desktop wired internet Cable modem Machine2 eepc701 Xubuntu 1O.04 wired machine1 cross ethernet cable Machine3 nokia n900 wireless to ...
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Creating multiple IP addresses in different subnets on Windows Vista

I am using Windows Vista, and only have 1 NIC. I know that in Linux, I can create IP aliasing such as: eth0 - 192.168.1.1 eth0:1 - 192.168.2.1 eth0:2 - 192.168.3.1 and access all 3 subnets with ...
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Single machine within Subnet Has One Tenth network speed

I have an issue regarding my network. One of the machines within the same subnet seems to have its download speed capped at 1 Mbps. Other machines within that subnet hit 11 Mbps or more. The machines ...
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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 ...
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Two Routers, Two Independent Networks?

My network routing (both routers are consumer-grade NETGEAR WNDR3700) is like this: Modem ==> Router 1 ==> Router 2 WAN Port I have Router 1 set to DHCP the entire home network. I want Router 2 to ...
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Two Ethernet cards (different subnet) and unable to ping eth1

I have been trying to solve this problem in weeks but am unable to do so. I am running RHEL5.3 and have two network interfaces (dhcp). I'm having problems accessing eth0 via ping or ssh when i'm in ...
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1answer
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Playing with default subnet mask: understanding the consequences

I'm playing with my router configuration, and I want to understand what happens from changing the default subnet mask from 255.255.255.0 to 255.255.0.0 is expected to do More details, I had Router ...
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1answer
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Can't show ip in different subnet at ipmessenger

I use IPMessenger to chat on LAN. It can show all IPs in the same subnet. For IPs in another subnet it does not show. How to setup my IPMESSENGER so I can chat to all?
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1answer
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Separate computers in my apartment can't communicate to each other?

In my apartment, the management provides the building with a network connection. I have my computer plugged into the ethernet coming out of the walls, and my friend who also lives in the apartment ...
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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 ...
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Netmask and ip are incompatible in dlink dir-300

I have Dlink Dir-300 wireless router. I have to set a static ip settings there. I specify Ip as 192.168.242.3 Netmask: 255.255.0.0. When I press enter it says that the ip is invalid. Although such ...
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Making two networks visible to each other

I have made a rough drawing of my network layout: The gateway, the two servers and the wifi router have a global IP address with a subnet mask of 255.255.255.240. The PCs have local IP addresses in ...
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pix 501, static route to d-link router (different subnet)

I have pix 501 cisco firewall with internal ip 192.168.10.1. I have connected d-link router (dir-655) to pix 501. The d-link router has internal ip 192.168.0.1 The picture would like something like ...
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What is subnetting?

What are the subnet mask, first available host address of subnet one (NOT subnet zero), and the maximum number of hosts per subnet for the network below? (You need to allow for maximum number of ...
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Subnets sets by a wifi and wire router

Is it generally possible to have wifi & wired clients of a router on the same subnet so that they see each other on the same LAN?
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Can you have a class C IP address with a subnet mask of 255.255.0.0?

Can you have a class C IP address with a subnet mask of 255.255.0.0? What happens when you have a setting like this?
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What is the logic behind subnet mask value? [duplicate]

Possible Duplicate: What are the essentials of a Subnet mask? hi, In all the machines having internet connections , i can see a value called subnet mask associated with the TCP/IP ...
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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 . . . . . . . . . ...
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changing the subnet on a DDWRT router

I'm currently working on a bridged openvpn setup between two places. My home lan uses a 192.168.1.x subnet, as does the remote location (which i can't change the subnet for anyway) which results, ...
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choose between different *.conf, based on current subnet

I have gentoo running on a laptop that I use on two different networks. When I'm in the office there are a couple of tweaks I need/want in make.conf and resolve.conf.head: I have access to a local ...
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Windows XP doesn't like small subnets?

This totally sounds like a bug to me, because my subnet mask and IP address should be valid by all accounts. My ISP has assigned me a fixed IP address of 65.110.7.20, with a subnet mask of ...
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1answer
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iptables: separate clients from each other

is there a way to separate clients in a subnet so that they cannot reach each other? The infrastructure currently looks like this: 192.168.0.1/24 Gateway, a CentOS box with iptables. ...
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1answer
651 views

Which subnet masks are valid for a subnetted Class B address?

Yes, this is a school question, and yes I already know the correct possible answers (supposedly), so I'm not going to bother posting them. Instead, I just want to understand the meaning of this ...
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How can I find any domain name that resolves to IP within a given net range?

For example, given the range: 172.128.0.0 - 172.191.255.255 I need to find some domain that resolves to an IP-adress within the range. Is it possible ? I'm using a Linux system.
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How do I establish a connection between 2 computers on different subnetworks?

computer A(192.168.1.134) needs to establish a UDP connection to computer C(192.168.0.30). As you can see both are on a different subnetwork. Now I have computer B which has 2 IP addresses, one for ...
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Set up two (2) IP addresses on the same network card?

I think it is possible to set up 2 IP addresses and subnet masks on one NIC in Windows XP. How can this be done?
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Changing Mac OS X 10.6 Routing after VPN'd In

I have a coffee shop around the corner that I use to do some work when I want to get away from home. They offer free wi-fi and I then use my Mac 10.6 VPN to log into my work network. I have "Send all ...
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local access network

what devices do i need to build a LAN? looking to make a LAN for about 6 PCs