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).

learn more… | top users | synonyms

33
votes
2answers
5k views

Why is ARP replaced by NDP in IPv6?

ARP was replaced by the NDP (Neighbour Discovery Protocol). But I don't know the exact reason for this. Are there any security issues in ARP? Why ARP is replaced by NDP? What are the advantages of ...
18
votes
3answers
83k views

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 ...
16
votes
5answers
59k views

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 ...
14
votes
2answers
7k views

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 ...
13
votes
2answers
19k views

What is the difference between ARP binding and DHCP address reservation?

In my TL-WR1043ND I have these functionalities and both of them pair an IP address to a MAC address. What is the difference? I red that the ARP one is there for security reasons, others say it is for ...
5
votes
3answers
30k views

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 of ...
5
votes
3answers
5k views

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 ...
5
votes
2answers
2k views

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. ...
5
votes
1answer
432 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 ...
5
votes
3answers
7k views

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 ...
4
votes
3answers
3k views

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?
4
votes
3answers
2k views

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 ...
4
votes
2answers
2k 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 ...
4
votes
2answers
986 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 ...
4
votes
2answers
14k views

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 ...
4
votes
1answer
6k views

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 ...
3
votes
4answers
12k views

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 ...
3
votes
3answers
765 views

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 ...
3
votes
1answer
64 views

Is my arp cache poisoned?

I have these entries, starting with 224 on my computer and on the virtual machines, they cannot be deleted nor modified. Why is that happening. I am running Win 8.1 C:\WINDOWS\system32>arp -a ...
3
votes
1answer
321 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 ...
3
votes
1answer
2k views

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 ...
3
votes
1answer
2k views

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
votes
1answer
895 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 ...
3
votes
0answers
200 views

Finding IP Address from MAC of a device in a different subnet

I am new to networking as such, but I have been searching a lot about the problem of finding IP from MAC for the past couple of days. I have a device whose MAC address I know and I have an Android app ...
3
votes
0answers
1k views

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
votes
1answer
7k views

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 ...
2
votes
2answers
3k views

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 ...
2
votes
3answers
2k views

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 ...
2
votes
2answers
3k views

Is there an easy way to do a host lookup by MAC address on a LAN?

Is there an easy way (on Linux) to implement host lookup by MAC address? In small local networks, it is easy to use for example arp-scan to find out the IP address of some device. I usually use ...
2
votes
1answer
4k 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 ...
2
votes
1answer
2k views

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 ...
2
votes
1answer
68 views

Setting up static IP for virtualbox

I was learning arpspoofing.I was using my Ubuntu machine as the Man in the middle, an Ubuntu in my virtualbox as the target and my default gateway(Which is 10.7.1.2) as the target gateway. In order to ...
2
votes
1answer
2k 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, ...
2
votes
1answer
2k views

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 "fix"...
2
votes
0answers
128 views

why doesn't system do ARP request broadcast before sending an IP packet?

First, let me describe the problem briefly. I have two programs which send IP packets from a host(192.168.0.101) to another host(192.168.0.106). These two programs are written respectively with C and ...
2
votes
0answers
126 views

Prevent ARP spoofing in AP, “wl deauthenticate” command

I am in a situation where I cannot do MAC filtering in an AP and I need to block a user that is ARP spoofing the network. I am trying to use the command wl deauthenticate to kick the client. And I ...
2
votes
1answer
2k views

How to set up a static/persistent ARP entry with OpenWRT 14.07, Barrier Breaker?

The title say it all, but here is the long version: I am trying to setup a way for my home server to automatically turn on using WakeOnLan, when a client tries to access it. My idea is that the ...
2
votes
0answers
2k 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 ...
2
votes
1answer
1k 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. ...
2
votes
1answer
447 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
votes
1answer
961 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? ...
1
vote
3answers
203 views

Is there a way to get “arp” to list devices on all subnets of a network?

I'm using arp -an on Mac OS X to list all devices on my network, but (as I understand it) this just lists devices on the same subnet. Is it possible to list all devices on the network and not just my ...
1
vote
6answers
7k views

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 possible?...
1
vote
1answer
1k views

Why am I not seeing ARP requests from my own machine in wireshark?

I am using Windows 7. I open up Wireshark and start a live capture with the filter: ip.src == THIS.IS.MY.IP I then go to a command line and do an arp -d * and ping a bunch of stuff. I see my ICMP ...
1
vote
1answer
449 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' ...
1
vote
2answers
654 views

What causes dropping of ARP response packets in a wireless network?

I have a network of wireless access points (APs) in my local area network (LAN). Some PCs in the network can get ping responses from some other PCs/devices in the network but not some others. I have ...
1
vote
1answer
139 views

Why does traceroute show a direct connection to my home network devices instead of going via the router?

I have 2 laptops connected to my home router, with the IP addresses 192.168.1.10 and 192.168.1.11. I use traceroute 192.168.1.11 from the first laptop and I get 1 22 ms 11 ms 33 ms ...
1
vote
2answers
70 views

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 ...
1
vote
2answers
10k 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 ...
1
vote
1answer
405 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 ...