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

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How to calculate CIDR notation from entries in a routing table

I have some entries in a routing table that were created using longest prefix matching, and I have to use those entries to determine the a.b.c.d/x notation (CIDR). This is an example entry: 11001000 ...
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794 views

access VPN machine macosx same subnet

I would like to access the office machine, which has a fixed IP, and is available only in its local LAN. Let say 192.168.1.100. I have a VPN with username/password connection and I am trying to ...
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4k views

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 ...
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501 views

How to find the network address of a given subnet?

How do I find the x th subnet of X.X.X.X /XX (300 th subnet of 172.16.0.0 /29)?
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819 views

route lan traffic through wirless mifi

I have a Windows 7 laptop accessing the internet through Verizon wireless MIFI configured as 192.168.1.1. It supports only 5 wireless connections, so I don't want to use up connections unnecessarily. ...
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How should I reserve IP addresses for my home LAN?

My Netgear router supports MAC-based IP reservation, and I'm setting up my very first home LAN where I want multiple Ubuntu servers to be given dedicated IP addresses. This is a consumer-grade router, ...
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2answers
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I'm using Cisco Packet Tracer for Simulation and got error “ip address overlaps with..etc”

The 1st row is for my router and the 2nd row is for my LAN. What's wrong? Is my IP addressing and subnetting wrong? I already checked my configuration.
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1answer
233 views

Is there a way to detect a LAN's IP and its subnet mask?

I'm not a English speaker, but I'll try my best make it clear: If your laptop connects to a unknown local network (through a wireless or wired router) and there's no DHCP service at all, and nobody ...
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1answer
311 views

How do subnetworks communicate with each other? [closed]

I'm a networking newbie and I'm a little bit confused about the difference between the terms: Zone Sub-network Topology I've seen network diagrams where a business's network was divided into three ...
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4k views

When I change the subnet for the LAN interface on a Sonicwall firewall the WAN interfaces go haywire. What should I do?

Our company's old subnet was 255.255.255.0. To adjust for growth we decided to implement a 255.255.248 subnet. Upon changing this in our Sonicwall's LAN interface, our WAN connections quit working ...
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213 views

connect to subnet via VPN

i have VPN setup which is like this: ########### internet ############## internet ############ LAN ############ # macbook # --------> # VPN server #----------># PC A # -------># PC ...
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Two hosts on same subnet can't see each other

I've got two routers with two separate public IP addresses on the same subnet, but I can't get them to talk to each other. Both are connected to the internet (ISP-provided gateway) via Ethernet ports ...
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873 views

Selectively route traffic through VPN - how to setup subnet on OS X Lion?

I am trying to route traffic only for a specific domain over a VPN. I found what seems to be the answer in another question: Create the file /etc/ppp/ip-up with following content: #!/bin/sh ...
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Accessing a wireless router on a different subnet

Okay, I'll try to describe how this network is set up. I didn't do it personally, but it has been described to me. Firstly, we get our internet from a 3G wireless USB card from ATT. This means that ...
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3answers
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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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1answer
970 views

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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742 views

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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361 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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3answers
1k views

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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2k views

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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113 views

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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923 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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3k views

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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554 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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214 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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202 views

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
1k views

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
1k views

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
573 views

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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480 views

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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193 views

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?