a device that connects to 2 or more networks and is capable of forwarding data packets into the direction of the ultimate destination based on information read from the packet and internal routing tables.

learn more… | top users | synonyms (1)

41
votes
11answers
36k views

What is the difference between UDP and TCP?

My router has two protocols (and a "both" option) that I can select when setting up port forwarding: UDP and TCP. What is the difference between these two protocols and when would you select one over ...
36
votes
5answers
12k views

Why does a hardware router perform better than a Linux router with better specs (RAM & CPU)?

I have a minimal CentOS 6.3, 64 bit acting as gateway with 4 NIC (1 Gbps), each bonded together one for public traffic and other for private, which performs NATing. It has 6 GB RAM and 4 logical ...
29
votes
4answers
3k views

Our wi-fi at work is ridiculously slow, will adding more range extenders improve it?

At work, we have two wireless networks (e.g., Work1 Work2); the Work2 is used downstairs and Work1 is used upstairs. However, both are notoriously slow. The connection is better when we are wired in, ...
28
votes
4answers
5k views

Is there a way to provide user-specific passwords for Wi-Fi?

Is there a way to provide user-specific passwords for Wi-Fi, so that different users have different passwords? I'd like to provide each user with a different password for my Wi-Fi connection.
23
votes
11answers
13k views

Is anyone else using OpenBSD as a router in the enterprise? What hardware are you running it on? [closed]

We have an OpenBSD router at each of our locations, currently running on generic "homebrew" PC hardware in a 4U server case. Due to reliability concerns and space considerations we're looking at ...
22
votes
4answers
101k views

What's the maximum number of wifi connections for a single WiFi router?

We've got a Draytek 2829VN Wifi router and I'm wondering how many concurrent connections I should expect a router of this kind to cope with? We are looking to connect 60 iPads! I'd also be ...
18
votes
3answers
5k views

Slowest wireless client dictates the connection quality of all others?

Not sure if this is the place to ask this, but I couldn't find a more appropriate StackExchange site. I heard that the quality of wireless connection follows the law of the lowest common denominator - ...
14
votes
4answers
15k views

What's the difference between a switch, a router, and a modem?

What's the difference between a switch, a router, and a modem?
13
votes
5answers
3k views

How can I split my personal network (with WIFI) from my office network?

I work from my home home office and have a VPN router to my company. I share the same network for my personal and office use. I have a WiFi Access Point, I don't want access to any of my company ...
12
votes
4answers
32k views

Any reason not to enable DoS Defense in my router?

I recently found a DoS Defense setting in my DrayTek Vigor 2830 router, which is disabled as default. I'm running a very small server on this network and I take it very serious to have the server up ...
12
votes
3answers
2k views

Can you recommend a good intro to iptables? [closed]

I have to setup a firewall on a Linux server (all my previous experience is with Windows). My rules are meant to be pretty simple - forbid all, allow some ports with all, allow some ports for specific ...
12
votes
3answers
2k views

Configuring a router to drop packets, introduce latency, corrupt data

I was wondering if anyone had any experience setting up an environment designed purposefully for poor performance when sending/receiving requests over a network. I'm developing an application and ...
10
votes
3answers
39k views

Bridging wlan0 to eth0

On arch Linux, I would like to mainly have eth0 (connected to bridged router) share the connection recieved from wlan0, Ive read tutorials but I'm not command sabby as other users are and don't ...
10
votes
6answers
8k views

monowall vs pfsense

I'm building a router out of a Mini-ITX pc + compact flash card setup and I'm trying to choose a suitable distro. My criteria are: Must be able to run from a CF card (so no excessive disk writes) ...
10
votes
3answers
3k views

Experiences with BIRD for BGP?

We're currently using Quagga with Debian Linux to run a full table BGP router. The set-up has been dead simple up to now, but we've come to a point where I have to reconfigure the router quite a bit, ...
10
votes
2answers
1k views

How to safely install a new IOS image on a Cisco device when the installed flash memory size isn't enough for two of them?

Today I was updating IOS on a Cisco 877 router, and a problem came up: the installed flash memory wasn't enough to hold both the old and the new IOS images, so the new one couldn't be uploaded unless ...
9
votes
3answers
6k views

Is there danger to virtualizing a router?

I had read on a few forums about pfSense that said it was dangerous to virtualize pfSense. The reason that was stated was an attacker could use pfsense as a spring board for an attack on the ...
9
votes
4answers
10k 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 ...
9
votes
1answer
2k views

Limit ICMP Per Source IP with IPTables

I have mistakenly thought that the limit module is per source ip, but it appears to be based on all requests: 577 36987 ACCEPT icmp -- * * 0.0.0.0/0 0.0.0.0/0 ...
8
votes
11answers
3k views

SOHO - throttle bittorrent traffic from problem users

I manage the network in a small office (SW dev is my "real job"), and there are a couple of users who beat the hell out of our internet connection by running bittorrent. Between the almost crippling ...
8
votes
7answers
21k views

What's the difference between a gateway and a router?

Here we can see the router is 67.23.27.187(first hop), but the gateway is 67.23.27.1. What's the difference between a gateway and a router? How does my computer know the IP of the router when only the ...
8
votes
4answers
1k views

Slow down individual connections passing through a Linux router?

We have a Linux server acting as a router/firewall for our office. Occasionally someone will upload a large file that takes up all our bandwidth. I don't want to implement any complex rules or traffic ...
8
votes
6answers
590 views

Cisco router for educational purposes

I want to buy a Cisco router to use on my home network. I'm just hoping to get a unit that is not too old and is not a SOHO model. I want to run the latest Cisco OS just to learn how Cisco does ...
8
votes
4answers
10k 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 ...
8
votes
3answers
39k views

How do I get IIS working and accessible outside my network behind a router? [closed]

My machine is running Windows 7 Ultimate. Here's what I've done (successfully) so far: Installed IIS 7.5 with PHP over FastCGI Got it working! When I go to http://localhost/index.php , my PHP ...
8
votes
4answers
950 views

Wireless AAA for a small, bandwidth-limited hotel

We (the tech I work with and myself) live in a remote northern town where Internet access is somewhat of a luxury, and bandwidth is quite limited. Here, overage charges ranging from few hundreds, to ...
7
votes
7answers
3k views

How do you manage your Linux iptables configuration on a machine acting as a router?

I have a couple Linux machines that act as routers/firewalls for my networks and I have a script that runs all the iptables commands to set my rules. This seems to me like a really silly way to do it ...
7
votes
4answers
2k views

Enterprise grade router, when to get it?

I manage an architect firm of 30 persons. I installed them a 'random' router from bestbuy (about $100). At the time they where 10 architects. Now they've grown to 30+ and are now experiencing a ...
7
votes
4answers
380 views

Why are ISP's installing routers on my site when the feed is a form of ethernet already?

I'm connected to 3 ISP's right now. Two of them already have routers at my site, the third one announced me "they need to install some equipment" when I requested BGP session. I can only assume they ...
7
votes
1answer
657 views

Why is routing neither CPU nor memory intensive? [closed]

I've recently been examining the performance statistics of my linux-based router, and have been surprised by what I'm seeing. I expected the routing workload to be much more taxing to RAM and CPU than ...
7
votes
2answers
4k views

Using dd-wrt Dynamic DNS client with CloudFlare

I'm trying to configure Dynamic DNS client on my router with dd-wrt (v24-sp2) firmware so it would dynamically change IP address in one of the DNS records. Unfortunately I encountered a problem… Here ...
7
votes
9answers
3k views

Need prosumer router/firewall/vpn/vlan/nat advice [closed]

Looking for a recommendation on a device (or devices I guess) to do router/firewall/vpn/vlan/nat functons for my home network. Right now, I'm doing this with an IPCop box, but I'd prefer a little ...
7
votes
4answers
7k views

Inexpensive, Reliable Captive Portal [closed]

I do some wifi hotspot installations, and a new client recently asked me if it would be possible to force users to his website when they first open their browsers. After some Googling I figured out ...
7
votes
7answers
1k views

Are there any good free Cisco router simulators out there?

I'm just starting some Cisco training and I would like to know if there are any freely available simulators available.
6
votes
4answers
2k views

Is Selling Old Cisco Routers a Security Issue?

I'm a system admin but I'm not Cisco certified and I'm not a network engineer. Basically I only use switches/routers/modems with a GUI. I've inherited a pile of old Cisco routers that are not in use ...
6
votes
1answer
3k views

Tomato firmware - View port 80 traffic

I'm using a WRT54GL router and i've installed the tomato firmware. Is there any shell command or somehting i can use to view all port 80 traffic? I want to se which internal ip has a connection to an ...
6
votes
2answers
2k views

Could someone explain why traceroute seems to be skipping a router on my network?

This is probably a very basic question, but I'm hopping someone can explain what's going on to me. I configured our wireless router at work to connect to directly to the router that provides our ...
6
votes
1answer
6k views

Routing 1 LAN + 2 WLANs + 2 WANs (failover) with DD-WRT on WRT54G2

I've installed DD-WRT v24-SP2 micro on a Linksys WRT54G2 v1.0, and I'd appreciate some help on setting up a not-so-trivial network. I've studied the documentation (notably ...
6
votes
3answers
5k views

What do “Unknown SSAP” and “Unknown DSAP” mean in tcpdump?

While trying to fix a problem with intermittently losing internet connection on a machine with a wireless connection to a router, I ran tcpdump and noticed packets with "Unknown SSAP" and "Unknown ...
6
votes
0answers
118 views

Configure Juniper M320 as Ethernet/STM transparent converter

There is Juniper M320. We need to move ALL the traffic from one port to another. Everything that comes to one port goes to another and vice versa. No snooping or any other processing is required. One ...
5
votes
5answers
4k views

How does a router get its IP address assigned?

I understand how a device connecting to a router (e.g. 72.73.74.75) gets assigned a local IP address (e.g. 192.168.1.5) using DHCP. BUT, how does the router itself get the IP address assigned from ...
5
votes
9answers
18k views

Getting an IP's MAC address from behind a router

I want to know, if possible, how to get a MAC address of an IP address if I am behind a router. I tried doing a ping to the IP and checking the arp table, but the only entry is the router's MAC. Any ...
5
votes
3answers
2k views

Can internet gateways be plugged straight into a layer 2 switch?

tl;dr Internet gateways (eg., cable modems, fiber optic gateways) don't function properly when they aren't behind a device with "layer 3" or routing capabilities, correct? Incredibly long backstory ...
5
votes
4answers
981 views

Does anyone use DD-WRT/OpenWRT etc. at their office? [closed]

Does anyone use any of the third party router/AP firmwares (DD-WRT, OpenWRT, Tomato, etc.) in an office environment? How many users does it handle well? How long have you been using it? I understand ...
5
votes
5answers
1k views

Routers vs. Switches

I know the difference between a router and a switch, but there are a few fuzzy spots in my understanding. When you uplink one switch into another, do they share mac address tables? Or is this a ...
5
votes
5answers
3k views

Host DHCP services on server or firewall/router?

I've been debating with myself about the best place for hosting a LAN's DHCP services. I have the option of either on a sonicwall firewall or a Windows 2008 server. The two things I was looking for ...
5
votes
9answers
14k views

I need to setup a Guest wi-fi SSID so customers/clients can connect to the internet, what's the best way to do that?

What are the best options out there to be able to provide a guest wireless internet access so they can't see the rest of devices in LAN?, what's the best and also cost effective appliance that will do ...
5
votes
2answers
8k views

Using iptables to block ALL outgoing traffic from one NIC?

I must pretty bad at Googling as this seems like a very basic question but I can't seem to find the answer anywhere... and man iptables is a very long read! I have two NICs - eth0 and eth1 - on a ...
5
votes
2answers
3k views

IPv6 can I use a link local address as my default Gateway?

can I set the default GW to be the Link Local address of the next hop router. I understand this is a strange thing to do, I'm mostly wondering it is possible?
5
votes
3answers
5k 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 ...