LAN, short for Local Area Network, is a network that connects multiple devices in a limited geographical area, such as a room, an apartment or a building. Currently, most LANs are based on Wi-Fi or Ethernet transmission.

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What should I pay attention to when I'm buying a network switch?

Since I'm not a hardware expert, I don't know what features make a network switch a good network switch. What should I pay attention, when I'm comparing the different models from different vendors?
15
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8answers
603 views

Building a LAN on in the woods

A very long time ago, I had to build a LAN for a bunch of laptops, in a couple of tents. We ended up bringing a bunch of generators, stringing about 2 miles of networking and power cables, and ...
14
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7answers
2k views

How much electricity is required to power 20 'average' computers on a LAN?

i trying to see how much electricity is required to power 'x' number of computers. I know it's a vague thing because some computers draw more than others (eg. diff chipsets, HDD, vid cards, PSU's, ...
13
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3answers
681 views

Prevent administrative users from assigning duplicate static IPs to their workstations

How can I prevent a user that is an administrator on their local machine from manually assigning an IP to their network adapter that is in use on a server? Some users have done this, and it's caused ...
13
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5answers
7k views

Per-user hosts file

Is there a way to define host aliases (like in /etc/hosts) on a per user basis, i.e. in a file /home/user/.hosts ? My primary objective is to easily share host aliases via rsync between the machines ...
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7answers
942 views

10 gigabit networks: Decieding between fiber and twisted pair

With a green field installation 10gbps network (no legacy equipment to support), why would one select one physical medium over the other? If left to impulse, I'd probably go with fiber optics over ...
9
votes
1answer
292 views

LAN: What are the things to look at when arriving in a new place

My company is moving to a new place, and the only thing I know about the cabling is that there are cables and a patch panel. I have no idea about the cable speed, quality, and I'm a software guy with ...
8
votes
10answers
44k views

Find which machine is using all the bandwidth

I need to know which machine is taking all the network bandwith. It's there a tool I can use to monitor my local network and know which machine is taking all the LAN bandwith? What do you think ...
8
votes
3answers
16k views

Load balancing & NAT-ing multiple ISP connections on Linux

I have two internet connections from two different ISPs and I need to balance the traffic originating to and from my network between the two ISPs. I am using Debian GNU/Linux. My set-up is like this ...
8
votes
4answers
54k views

How to route different traffic thru different network interfaces (in Windows)

I've searched for details on how to do this but I've been unsuccessful - I wondered if someone could offer up some advice. So, let's say I have 2 network cards (LAN and 3G in my instance), both ...
8
votes
3answers
642 views

Migrate raw disk image over LAN

Here is my situation: Two dedicated servers in the same datacenter with gigabit ethernet between them. Both dedicated servers booted into a rescue environment based on Debian Squeeze with extra ...
8
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4answers
5k views

Linux router: ping doesn't route back

I have a Debian box which I'm trying to set up as a router and an Ubuntu box which I'm using as a client. My problem is that when the Ubuntu client tries to ping a server on the Internet, all the ...
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7answers
890 views

Best choice of private addresses for a “device area network”

I'm building an appliance consisting of several subdevices connected by ethernet inside the appliance. The appliance will connect to the customer network. The customer network can be using private ...
7
votes
2answers
2k views

Do switches sometimes need rebooting?

In your opinion, do switches sometimes need a restart? I'm asking this because today our NAS stopped working properly, and was only fixed when we restarted the switch it was attached to.
7
votes
3answers
5k views

IPSec for LAN traffic: Basic considerations?

This is a follow-up to my Encrypting absolutely everything... question. Important: This is not about the more usual IPSec setup, where you want to encrypt traffic between two LANs. My basic goal is ...
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votes
4answers
6k views

What happens if you short-circuit a network patch cable?

Today we had some network problems and after some nested-interval trial and error we tracked down a small 4-port hub where someone had connected both ends of a patch cable to the same hub. After ...
6
votes
4answers
7k views

Should a webserver in the DMZ be allowed to access MSSQL in the LAN?

This should be a very basic question and I tried to research it and couldn't find a solid answer. Say you have a web server in the DMZ and a MSSQL server in the LAN. IMO, and what I've always ...
6
votes
4answers
6k views

Windows 7 network performance tuning for LAN

I want to tune Windows 7 TCP stack for speed in a LAN environment. Bit of background info: I've got a Citrix XenServer set up with Windows 2008R2, Windows 7 and Debian Lenny with Citrix kernel, ...
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1answer
4k views

iptables - allow connections only from LAN

Is there a way to deny all external traffic (WAN) to SSH and allow only local traffic (192.168.0.1 to 192.168.0.255) and what would be the rule?
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votes
10answers
4k views

Find Sniffer on LAN

HI, What tools or techniques are available for *nix and Windows that help in finding if someone else on the LAN is using a sniffer? Having said that and strongly considering that there are tools out ...
5
votes
2answers
372 views

Why ethernet cables must be ended with specific arrangement

I just accepted that ethernet cables CAT 5 and more must be ended with specific arrangement. I learned when I ending my cables to take attention that either end must be in same arrangement(568A or ...
5
votes
3answers
4k views

Unable to connect on natted server from a host computer on the same LAN using public IP address

I have a server statically NAT’d using a registered IP address and it is accessible from the outside. The problem is I cannot access my server from the inside using the registered IP address with a ...
5
votes
2answers
4k views

Enable user registration - eJabberd

I am a complete n00b to configuring Jabber/XMPP servers and I am hoping to get some help getting set up. I have done all of this and installed pidgin. I seem to be able set up my "admin-user" in ...
5
votes
4answers
5k views

Can't communicate between lan ports on openwrt router

I've got a WBMR-HP-G300H Buffalo Airstation router on which I've installed the lates OpenWRT software. All is working well (ADSL, WIFI etc) except for one niggle. I can't communicate between lan ...
4
votes
3answers
8k views

Best way to create a vpn between two windows machines?

I'm looking for way to create a VPN between two windows machines. I want the installed software to behave as if the two computers are connected through a LAN. What's the best (free) way to do it? ...
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votes
2answers
2k views

Password protect wired LAN?

The title is not a mistake, I really am talking about wired, not wireless. Essentially, I was wondering if it was possible to password-protect a LAN wired network to enhance security and only allow ...
4
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3answers
561 views

Several switches vs one switch for on LAN of 60 computers?

A. Is using one network switch is faster vs 3-4 network switches connected together in same room? B. Is there difference in speed at all between cheap switch and more expensive model? P.S. network ...
4
votes
6answers
4k views

How do I point my browser to a specific NIC on my machine

I am on a local area network that has no external access to the internet. However I have been tasked to find a way to allow certain machines to access the web (HTTP, HTTPS, etc) via a wireless card ...
4
votes
6answers
2k views

Encrypting absolutely everything, even within the LAN

Has anybody tried that approach already? I'm really considering it: Instead of relying on network based IDS etc., every packet must use encryption which was initiated by a certificate issued by my own ...
4
votes
4answers
2k views

Should / Can I use DNS Records to list “Private Hosts in Private LANs”?

This is a theoretical Question: Given I have several Serves that both have a Public IP Address as well as a private IP Adress (192.xxx Range). Both Addesses are used for different Services. I do not ...
4
votes
4answers
1k views

How to wire 20 computers and 20 phones and 1 server into LAN?

I have currently 3 switches Two Netgear JFS524 with 24 slots, One Belkin with 16 slots. Server DSL Internet Router. Main question is how to connect switches together, two Netgear's are next to each ...
4
votes
2answers
1k views

Simulate internet routers, dns in a lab?

I need to test my software runs across the internet, i.e. two machines can talk to each other via host addresses and name resolution with routers and port-forwarding in between. What's the best way to ...
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votes
4answers
16k views

What happens if two computers have the same MAC?

Possible Duplicate: Can duplicate MAC addresses on same LAN cause trouble? What happens to network traffic on a switched LAN if two devices have the same MAC (probably because one is ...
4
votes
2answers
328 views

Best security practice for small networks - wifi, lan,

We regularly setup small networks for clients in different locations to allow them to work on different products now the question what should be the best security practice. Currently we have a wifi ...
4
votes
1answer
2k views

Are Link-Local routes necessary (IPv4)?

I noticed in my routes output in RHEL6 (and most 2.6.x series Linux), for every interface I see the creation of the following route in my kernel routing table: 169.254.0.0 0.0.0.0 ...
4
votes
1answer
872 views

One Router and Two Switches

I have two switches and one VPN router and Two Internet ADSL Routers. The internet connection has been provided to two groups. Group A has no restrictions, that is for Executives and Department Heads. ...
3
votes
6answers
492 views

Gaming on an office lan [closed]

don't shoot me for this one. I'm wanting to get a few of us in our team (say 5 players) to start playing a network game in the office (you know... team building and all that ;) ) - thinking that ...
3
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3answers
5k views

Access ports versus trunk ports?

Can someone please explain the difference between access ports and trunk ports on a switch? I'm starting to learn networking, and my understanding is that access ports are used to connect endpoints ...
3
votes
3answers
5k views

How to configure bind9 to be a local DNS only with no internet access?

I want to configure bind9 to be a local DNS only with no internet access at all. So I have 5 PCs in my virtual domain xy.com. Within this domain there is no access to the internet. The DNS server ...
3
votes
4answers
160 views

Possible Issue With (what I think is) a Virtual Network

This really isnt my area of expertise...and it may be obvious, but here it is: We have what I guess you could call a virtual network. We have 4 locations in 4 cities connected by broadband internet ...
3
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5answers
625 views

What are the best LAN communication systems? [closed]

What are the best messaging and VOIP systems for medium to large corporate networks? What have you found to be the best in your experience and why? It should support: Instant messaging Video and ...
3
votes
6answers
3k views

Setting up DNS for a LAN without a top-level domain name

I am attempting to set up a LAN's domain-name server. My router has a given domain name from the ISP- something like foobar21.verizon.com. I would like to assign my local computers names such as, ...
3
votes
2answers
2k views

Cannot ping over LAN until a ping is received

I have two OSX machines on a local subnet. Pings from Machine A to Machine B consistently timeout until Machine B pings Machine A. After B pings A, A can successfully ping B, but this success is ...
3
votes
2answers
725 views

2 RJ45 connectors on a one WAN cable

I encountered strange setup on a network at company where I do some work. They have internet connection from small ISP located in the same building, all I see is one CAT5 cable with 2 RJ45 ...
3
votes
2answers
1k views

How ISPs will assign IPs /subnets for end users in IPv6

Consider two scenarios: The end user has a simple computer, dual-stack The end user has a LAN behind a dual-stack router How will ISPs differentiate each one of these kind of users in IPv6? An ...
3
votes
4answers
2k views

What are the advantages/disadvantages for using a single strand of fiber for a full-duplex link?

I have seen telcos install one-strand fiber links at full-duplex, but haven't found much documentation about this configuration. What are the bandwidth limitations, troubleshooting complications, ...
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4answers
770 views

Resolving IP address conflicts on a LAN

We have our LAN set up with DHCPD providing fixed IP addresses to the systems. However we are facing IP address conflicts if some one connects a laptop and assigns an IP address belonging to another ...
3
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4answers
6k views

What are good and bad jitter times for a LAN

Ive just ran jperf (frontend to iperf) on our network between 2 workstations, its recorded jitter between 0.033ms and 0.048ms. Is this good or bad? Are there more variables that i would need to ...
3
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1answer
67 views

Unknown LAN textbook title

I am preparing for my computer networks exam and I stumbled upon this textbook excerpt. I cannot find this book in google, I don't know the author or the title. Do any of you recognize this book?
3
votes
2answers
572 views

Why is my SSH session timing out in less than a minute?

Within a minute of connecting to my remote Linux server through SSH, my session times out and I cannot contact the server until a few seconds have passed. Meanwhile, I'm connected to other servers ...