ARP (Address Resolution Protocol) is a protocol used to find an address from the link layer (Ethernet, for example) from the network layer address (such as an IP address).

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Windows 7: The ARP entry addition failed: Access is denied

I'm on Windows 7 and am trying to assign a static arp entry for my default gateway using the command: arp -s 172.24.7.254 00-05-01-f9-28-00 172.24.1.20 But I get the following error: The ARP ...
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how does 'ping' command really work?

How does the ping command really work? Specifically where does the ARP (Address Resolution Protocol) come into picture? I was asked this question in an interview and I was not able to come up with ...
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Inverse ARP lookup

How can I do an inverse ARP lookup in Windows and/or Linux? Say that I have the MAC address of wireless access point which is up and running in the network, but I forgot it's IP address?
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What are the purposes of the addresses in this ARP table?

I've seen this on my Windows 7 computer, and searches have turned up others in Vista/7 who have seen the same. However, I've not yet found (or perhaps have just missed) a good explanation for this. ...
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Detect IP Conflicts on Network

I have a Wireless WAN network that I am managing devices on. We recently had an IP conflict that took us over 10 months to find (we had no idea there was even a conflict until we were pinging a ...
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Given a PC's MAC address, can I find its IP?

Is there a way to get the IP address when all you have is the MAC of an item?
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What adds these Multicast IPs to the ARP table, as static entries?

(Similar to my previous question, but addressing a separate aspect which has gone unanswered.) I've seen this on my Windows 7 computer, and searches have turned up others in Vista/7 who have seen the ...
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1answer
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Does the order of entries in the routing table matter?

Does the routing order matter: > route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 123.x.x.151 0.0.0.0 255.255.255.255 UH ...
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1answer
179 views

Get IPv6 address of an IPv4 machine?

Given two machines on a local network, both connected via IPv4 and IPv6, can machine A get the IPv6 of machine B if it has machine B's IPv4 address? I presume the ARP cache should be able to provide ...
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2answers
661 views

How is ARP about two VMs running on VMWare?

I know that systems in network connect together with IP and Mac address ,But insofar as i now all of OSs running on virtual machine use a common network card.I want to know how another systems connect ...
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1answer
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Why does a PING reply require an ARP request for the originating hosts MAC?

I have a scenario as depicted below. Here two host machines are connected via a hub: Ok, so host-1 wants to ping host-2 and i have setup wireshark on a 3rd host connected to the same hub. Now ...
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Why do we need IP addresses to communicate within the local network segment?

Because MAC addresses are only usable across the local network segment, we use IP addresses to communicate with other segments via routers. Meanwhile, for local targets, ARP is used to translate IPs ...
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Wireless router's ip address

Does my wireless router have an ip address that's independent of my computer's ip address? Is there any way to determine what that ip address is? Note: I'm not talking about the internal router ip ...
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3answers
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How to run webcam software only when I am not home (phone is not on the LAN)?

Currently I've got my user cron starting Motion on a timer when I typically leave for work, and then killing it when I typically get home, so I can watch my cat/burglars/etc: 0 9 * * * killall motion ...
3
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1answer
288 views

Can someone explain how this happened?

I seem to be having some odd results when running netdiscover on my home network. From the cable modem to my scanner (skipping a few peripherals), here's the basic layout: The cable modem is ...
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2answers
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How can I block NetCut in my network?

I am facing a huge problem in my shared network. We are almost 30 users sharing a single internet connection. Someone is using NetCut and taking all the bandwidth from us. Not allowing even to send ...
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1answer
300 views

Why would an iPod Touch and PS3 respond to netdiscover as 0.0.0.0?

Only slightly related to this question, because it was discovered in the same scan: Can someone explain how this happened? When running netdiscover on my home network, my iPod Touch (identified by ...
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1answer
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Home Networking: Connecting a switch to a router

I have the following network setup: EE Fibre going to a BT Infinity modem. EE Brightbox router, WAN port connected to the EE Modem. Port 1 connected to a Netgear Gigabit Switch 8 Port Netgear GS308 ...
3
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1answer
622 views

Detect changes to routing table or address resolution protocol on Windows 7

On two different Win7 PCs we're having a very specific problem where connecting a device which uses a RNDIS driver sometimes disrupts the PC's network adapter connection (we detect this because we ...
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1answer
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How can I stop my computer from doing arp poisoning attacks?

I have a small LAN in my home about 4 - 5 computers. The problem is that when there are usually 3 or more pc's online we keep losing the Internet access randomly about every 2 minutes. So we took a ...
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2answers
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target IP address is same as source IP address in ping ARP request

I am working on wireless driver. But I feel this question is just a general network question. I saw strange content of the first ping packt, which is an arp request, where the target IP address is ...
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3answers
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Windows XP Home issuing about 20 ARP requests a second

I have been asked to remotely fix a family member's computer that is running "slow". I've had them run any number of S&D and AVG scans, even in safe mode, but they find nothing of interest. In ...
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1answer
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Can I temporarily affect ARP table without using `arp` command directly?

I have some knowledge about arp command under linux which can help modify the ARP table. Now I want to temporarily affect ARP table(add, delete and change) entries without the help of arp. For ...
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1answer
338 views

Excessive rate of ARP requests from Windows 7 spooler service when network printer is off

I'm having series of ARP requests broadcast by a laptop over WLAN, asking MAC address for a range of IP (192.168.0.62 --> 192.168.0.94.) The process runs for the range, stops for a 20 or 30 seconds, ...
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1answer
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Wireless fails until one does arp -d 192.168.1.1

My wireless fails from between some minutes after being connected to half an hour or more. Symptoms: new pages not opening downloads already in progress continue ping 8.8.8.8 not working The ...
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1answer
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How do i get the ARP list from our router (programmatically / in the command line)?

At our office we have a netgear router, I'd like to poll it to see who's in the office (preferably on the command line) because i'm weird like that.. Is their a standard way of doing this? is it ...
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DD-WRT router causing IP address conflicts across network

My DD-WRT router has lost its mind! (Caveat: technically neither of these devices are "routing". I'm going to call them routers anyway.) I just set up two DD-WRT routers, one as a WAP (working fine) ...
2
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1answer
337 views

Wireless card fails to receive ARP resolution answer from Router

I have a Windows Vista laptop here with an Atheros AR5007EG wireless card. When attempting to connect it with an AVM Fritzbox 7330 the following happens: Laptop successfully negotiates DHCP and ...
2
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1answer
661 views

arp add 255.255.255.255 ff:ff:ff:ff:ff:ff (router)

If I add arp entry in router config like this: arp add 255.255.255.255 ff:ff:ff:ff:ff:ff Open specific port: port: 1009 ip: 255.255.255.255 Will it broadcast message to all connected devices? ...
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3answers
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What is the I.P. address 224.0.0.22 for? [duplicate]

Possible Duplicate: What are the purposes of the addresses in this ARP table? I notice that ANY computer that I go to, if I do a arp -a command from a command line, I receive a reply back ...
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1answer
225 views

Two network routers on the same IP

I have a network with several routers serving as accesspoint connected trough a switch to a central DLS/router/AP. One of the slave router have been somehow partially reset (SSID changed to 'default' ...
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2answers
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Find new ips on network

The solution I want to solve is to discover newly connected ip (and preferably mac and vendor) on the local network. So far I've tried arp-scan and nmap. I like arp-scan mainly because it's fast ...
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1answer
909 views

Windows method to detect ARP Poisoning in my local network (LAN)?

(This question comes from this thread, and is intended to remain as a reference question/answer pair for more generic ARP network detection not limited to WiFi, or without the need of the specific ...
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1answer
3k views

Is there a way to execute an arp spoof on Windows?

You can easily set up arp spoofs on linux using the arpspoof command in terminal. My question is - is there a piece of software that would allow you to do the same on Windows? So far I've seen ...
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1answer
214 views

Arp table on a multi switch vlan

Lets say I have multiple cisco switches that are all on the same VLAN. The question is: If I do "arp -a" on a pc that is connected to one of the switches. Do I get the Ip and Mac addresses of all ...
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1answer
506 views

what's IPv6 analogue for IPv4 `arp -an` and “arp who-has”?

In IPv4 world, when you want to talk to another computer, you ask which MAC address claims a given IPv4 address, the arp who-has ... tell ... exchange as per tcpdump, and a cache of such mappings from ...
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1answer
620 views

ARP: 'Who has' broadcast resulting in TCP segment losses

I have an issue with a simple TCP connection between two PCs (both Windows XP SP3) connected by direct wire to each other. These PCs have IP address 10.10.10.1 (server) and 10.10.10.2 on the network ...
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1answer
831 views

wake on lan from internet - problems with router: arp

I've ubuntu server on lan with static IP within lan, I use router: DSL-2640B. For waking I use program called "wolcmd". From within lan network it is very easy to wake up the machine. I just issue ...
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Is Wake On LAN supposed to work even after AC power reset?

So, if you unplug the AC power cable from the wall and re-connect it to the PC Power Supply, is the Wake On Lan functionality still supposed to work on a PC? The WoL functionality is enabled in Bios ...
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0answers
41 views

dhcp no lease because of not-DAD mode

My virtual machine does not receive an IP lease anymore. Manually requesting a new ip lease by 'ifdown/ifup eth0' or 'dhclient eth0' or 'service network restart' don't work either. The error is ...
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0answers
96 views

ARP for a multihomed machine (Linux)

I try to configure two interfaces on my server to behave as independently as possible on the same medium. However I have some problems with ARP (maybe related to ARP flux). I hope somebody can ...
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0answers
956 views

Wake-on-LAN stops working after a few hours

I have a Linux server (Ubuntu 12.04.03) which serves as the internet gateway for our LAN of about 15 PCs. That is, eth0 on the Linux server is the Internet, and eth1 plugs into an unmanaged switch (a ...
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1answer
896 views

Window 8 machine cannot ping devices on same subnet

After returning from vacation during which several Windows updates were applied and my router suffered a hard power cycle, my Windows 8 Desktop can no longer ping other devices on the same subnet. ...
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3answers
312 views

Duplicate MAC but different IP on home router

Would it be possible to have duplicate MAC addresses but different IPs on a home router? My questions are listed below. I don't have computers with the same MAC. The second connection displays no ...
0
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1answer
70 views

IP Address in ARP Cache

I am learning more about networking... I am working on some Wireshark Labs and the subject is ARP. Screen shot of ARP Cache During the lab I did an ARP Cache dump. Fired up Wireshark and went to a ...
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How does a router find the MAC address of next hop router?

I know that in an Ethernet LAN, the ARP protocol is used to get a MAC address from an IP address. How does my router get the MAC address of another router on an external network if ARP is not ...
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2answers
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arp requesting to another subnet, how?

I'm wondering if I have a computer in subnet A with IP address 192.168.123.1, and a computer with IP address 192.168.124.1 in a different subnet. Both networks are connected with a router. If I want ...
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1answer
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Bridge-mode networking and virtual network adapters

Say I have physical network adapter eth0 on my host machine and VirtualBox virtual machine with bridged network. Host and virtual machine have different IP addresses in the same network. I can easily ...
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1answer
127 views

Values below “Starting IP address” in linksys router.

In my basics setup in linksys router, I've set Starting IP address to 192.168.1.100. How can you explain that in ARP/RARP Table I can see users with addresses 192.168.1.25 and 192.168.1.26?
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why do I get a different MAC address using arp and ifconfig?

# ifconfig eth1 Link encap:Ethernet HWaddr 00:1e:8c:10:xx:xx # arp Address HWtype HWaddress Flags Mask Iface 192.xxx.x.x ether ...