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<title>Address Resolution Protocol</title>

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Address Resolution Protocol

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The Address Resolution Protocol (ARP) is a <a href="Communication_protocol" title="Communication protocol">communication protocol</a> for discovering the <a href="Link_layer" title="Link layer">link layer</a> address, such as a <a href="MAC_address" title="MAC address">MAC address</a>, associated with a <a href="Internet_layer" title="Internet layer">internet layer</a> address, typically an <a href="IPv4_address" class="mw-redirect" title="IPv4 address">IPv4 address</a>. The protocol, part of the <a href="Internet_protocol_suite" title="Internet protocol suite">Internet protocol suite</a>, was defined in 1982 by <style data-mw-deduplicate="TemplateStyles:r1238218222">

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</style><a href="RFC_(identifier)" class="mw-redirect" title="RFC (identifier)">RFC</a> <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc826">826</a>, which is <a href="Internet_Standard" title="Internet Standard">Internet Standard</a> STD 37.

ARP enables a host to send an IPv4 packet to another node in the local network by providing a protocol to get the MAC address associated with an IP address. The host broadcasts a request containing the node's IP address, and the node with that IP address replies with its MAC address.

ARP has been implemented with many combinations of network and data link layer technologies, such as <a href="IPv4" title="IPv4">IPv4</a>, <a href="Chaosnet" title="Chaosnet">Chaosnet</a>, <a href="DECnet" title="DECnet">DECnet</a> and Xerox <a href="PARC_Universal_Packet" title="PARC Universal Packet">PARC Universal Packet</a> (PUP) using <a href="IEEE_802" title="IEEE 802">IEEE 802</a> standards, <a href="FDDI" class="mw-redirect" title="FDDI">FDDI</a>, <a href="X.25" title="X.25">X.25</a>, <a href="Frame_Relay" title="Frame Relay">Frame Relay</a> and <a href="Asynchronous_Transfer_Mode" title="Asynchronous Transfer Mode">Asynchronous Transfer Mode</a> (ATM).

In <a href="Internet_Protocol_Version_6" class="mw-redirect" title="Internet Protocol Version 6">Internet Protocol Version 6</a> (IPv6) networks, the functionality of ARP is provided by the <a href="Neighbor_Discovery_Protocol" title="Neighbor Discovery Protocol">Neighbor Discovery Protocol</a> (NDP).

<div class="mw-heading mw-heading2"><h2 id="Operating_scope">Operating scope</h2></div>

The Address Resolution Protocol is a <a href="Request-response" class="mw-redirect" title="Request-response">request-response</a> protocol. Its messages are directly encapsulated by a link layer protocol. It is communicated within the boundaries of a single <a href="Subnetwork" class="mw-redirect" title="Subnetwork">subnetwork</a> and is never <a href="Routed" class="mw-redirect" title="Routed">routed</a>.

<div class="mw-heading mw-heading2"><h2 id="Packet_structure">Packet structure</h2></div>

The Address Resolution Protocol uses a simple message format containing one address resolution request or response. The packets are carried at the <a href="Data_link_layer" title="Data link layer">data link layer</a> of the underlying network as raw payload. In the case of Ethernet, a <style data-mw-deduplicate="TemplateStyles:r886049734">

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</style>0x0806 <a href="EtherType" title="EtherType">EtherType</a> value is used to identify ARP frames.

The size of the ARP message depends on the link layer and network layer address sizes. The message <a href="Header_(computing)" title="Header (computing)">header</a> specifies the types of network in use at each layer as well as the size of addresses of each. The message header is completed with the operation code for request (1) and reply (2). The payload of the packet consists of four addresses, the hardware and protocol address of the sender and receiver hosts.

The principal packet structure of ARP packets is shown in the following table which illustrates the case of IPv4 networks running on Ethernet. In this scenario, the packet has 48-bit fields for the sender hardware address (SHA) and target hardware address (THA), and 32-bit fields for the corresponding sender and target protocol addresses (SPA and TPA). The ARP packet size in this case is 28 bytes.

<caption>Internet Protocol (IPv4) over Ethernet ARP packet

</caption>

<th style="min-width:42px; border-bottom:none; border-right:none;">Offset

</th>

<th style="border-left:none;"><a href="Octet_(computing)" title="Octet (computing)">Octet</a>

</th>

<th colspan="8">0

</th>

<th colspan="8">1

</th>

<th colspan="8">2

</th>

<th colspan="8">3

</th></tr>

<tr>

<th style="min-width: 42px;border-top: none;">Octet

</th>

</th>

<th style="min-width:11px;">0

</th>

<th style="min-width:11px;">1

</th>

<th style="min-width:11px;">2

</th>

<th style="min-width:11px;">3

</th>

<th style="min-width:11px;">4

</th>

<th style="min-width:11px;">5

</th>

<th style="min-width:11px;">6

</th>

<th style="min-width:11px;">7

</th>

<th style="min-width:11px;">8

</th>

<th style="min-width:11px;">9

</th>

<th style="min-width:16px;">10

</th>

<th style="min-width:16px;">11

</th>

<th style="min-width:16px;">12

</th>

<th style="min-width:16px;">13

</th>

<th style="min-width:16px;">14

</th>

<th style="min-width:16px;">15

</th>

<th style="min-width:16px;">16

</th>

<th style="min-width:16px;">17

</th>

<th style="min-width:16px;">18

</th>

<th style="min-width:16px;">19

</th>

<th style="min-width:16px;">20

</th>

<th style="min-width:16px;">21

</th>

<th style="min-width:16px;">22

</th>

<th style="min-width:16px;">23

</th>

<th style="min-width:16px;">24

</th>

<th style="min-width:16px;">25

</th>

<th style="min-width:16px;">26

</th>

<th style="min-width:16px;">27

</th>

<th style="min-width:16px;">28

</th>

<th style="min-width:16px;">29

</th>

<th style="min-width:16px;">30

</th>

<th style="min-width:16px;">31

</th></tr>

<tr>

<th style="width:35px;">0

</th>

<th style="width:30px;">0

</th>

<td colspan="16"><abbr title="A value of 1 indicates Ethernet.">Hardware Type</abbr> (1)

</td>

<td colspan="16"><abbr title="0x800 indicates IPv4">Protocol Type</abbr> (0x0800)

</td></tr>

<tr>

<th style="width:35px;">4

</th>

<th style="width:30px;">32

</th>

<td colspan="8">Hardware Length (6)

</td>

<td colspan="8">Protocol Length (4)

</td>

<td colspan="16">Operation

</td></tr>

<tr>

<th style="width:35px;">8

</th>

<th style="width:30px;">64

</th>

<td colspan="32" style="border-bottom: none;">Sender Hardware Address

</td></tr>

<tr>

<th style="width:35px;">12

</th>

<th style="width:30px;">96

</th>

</td>

<td colspan="16" style="border-right: none;">Sender Protocol Address↴

</td></tr>

<tr>

<th style="width:35px;">16

</th>

<th style="width:30px;">128

</th>

<td colspan="16" style="border-left: none;">↪Sender Protocol Address (cont.)

</td>

<td colspan="16" style="border-bottom: none;">Target Hardware Address

</td></tr>

<tr>

<th style="width:35px;">20

</th>

<th style="width:30px;">160

</th>

</td></tr>

<tr>

<th style="width:35px;">24

</th>

<th style="width:30px;">192

</th>

<td colspan="32">Target Protocol Address

</td></tr></tbody></table>

<dl><dt>Hardware Type (HTYPE): 16 bits</dt>

<dd>This field specifies the network link protocol type.<a href="#cite_note-IANA-1">[1]</a> In this example, a value of 1 indicates <a href="Ethernet" title="Ethernet">Ethernet</a>.</dd>

<dt>Protocol Type (PTYPE): 16 bits</dt>

<dd>This field specifies the internetwork protocol for which the ARP request is intended. For IPv4, this has the value 0x0800. The permitted PTYPE values share a numbering space with those for <a href="EtherType" title="EtherType">EtherType</a>.<a href="#cite_note-IANA-1">[1]</a><a href="#cite_note-rfc9542-2">[2]</a></dd>

<dt>Hardware Length (HLEN): 8 bits</dt>

<dd>Length (in <a href="Octet_(computing)" title="Octet (computing)">octets</a>) of a hardware address. For Ethernet, the address length is 6.</dd>

<dt>Protocol Length (PLEN): 8 bits</dt>

<dd>Length (in octets) of internetwork addresses. The internetwork protocol is specified in PTYPE. In this example: IPv4 address length is 4.</dd>

<dt>Operation (OPER): 16 bits</dt>

<dd>Specifies the operation that the sender is performing: 1 for request, 2 for reply.</dd>

<dt>Sender Hardware Address (SHA): 48 bits</dt>

<dd>Media address of the sender. In an ARP request this field is used to indicate the address of the host sending the request. In an ARP reply this field is used to indicate the address of the host that the request was looking for.</dd>

<dt>Sender protocol address (SPA): 32 bits</dt>

<dd>Internetwork address of the sender.</dd>

<dt>Target hardware address (THA): 48 bits</dt>

<dd>Media address of the intended receiver. In an ARP request this field is ignored. In an ARP reply this field is used to indicate the address of the host that originated the ARP request.</dd>

<dt>Target protocol address (TPA): 32 bits</dt>

<dd>Internetwork address of the intended receiver.</dd></dl>

ARP parameter values have been standardized and are maintained by the <a href="Internet_Assigned_Numbers_Authority" title="Internet Assigned Numbers Authority">Internet Assigned Numbers Authority</a> (IANA).<a href="#cite_note-IANA-1">[1]</a>

The <a href="EtherType" title="EtherType">EtherType</a> for ARP is 0x0806. This appears in the Ethernet frame header when the payload is an ARP packet and is not to be confused with PTYPE, which appears within this encapsulated ARP packet.

<div class="mw-heading mw-heading2"><h2 id="Layering">Layering</h2></div>

ARP's placement within the <a href="Internet_protocol_suite" title="Internet protocol suite">Internet protocol suite</a> and the <a href="OSI_model" title="OSI model">OSI model</a> may be a matter of confusion or even of dispute. <a href="RFC_(identifier)" class="mw-redirect" title="RFC (identifier)">RFC</a> <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc826">826</a> places it into the <a href="Link_Layer" class="mw-redirect" title="Link Layer">Link Layer</a> and characterizes it as a tool to inquire about the "higher level layer", such as the Internet layer.<a href="#cite_note-3">[3]</a> <a href="RFC_(identifier)" class="mw-redirect" title="RFC (identifier)">RFC</a> <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc1122">1122</a> also discusses ARP in its link layer section.<a href="#cite_note-rfc1122-4">[4]</a>

Richard Stevens places ARP in OSI's data link layer<a href="#cite_note-5">[5]</a> while newer editions associate it with the network layer or introduce an intermediate OSI layer 2.5.<a href="#cite_note-6">[6]</a>

<div class="mw-heading mw-heading2"><h2 id="Example">Example</h2></div>

Two computers, A and B, are connected to the same <a href="Local_area_network" title="Local area network">local area network</a> with no intervening <a href="Gateway_(telecommunications)" title="Gateway (telecommunications)">gateway</a> or <a href="Router_(computing)" title="Router (computing)">router</a>. A has a packet to send to IP address 192.168.0.55 which happens to be the address of B.

Before sending the packet to B, A broadcasts an ARP request message – addressed with the broadcast MAC address FF:FF:FF:FF:FF:FF and requesting response from the node with IP address 192.168.0.55. All nodes of the network receive the message, but only B replies since it has the requested IP address. B responds with an ARP response message containing its MAC addresses which A receives. A sends the data packet on the link addressed with B's MAC address.

Typically, network nodes maintain a <a href="Lookup_table" title="Lookup table">lookup</a> cache that associates IP and MAC addressees. In this example, if A had the lookup cached, then it would not need to broadcast the ARP request. Also, when B received the request, it could cache the lookup to A so that if B needs to send a packet to A later, it does not need to use ARP to lookup its MAC address. Finally, when A receives the ARP response, it can cache the lookup for future messages addressed to the same IP address.<a href="#cite_note-7">[7]</a>

<div class="mw-heading mw-heading2"><h2 id="ARP_probe">ARP probe</h2></div>

An ARP probe in IPv4 is an ARP request constructed with the SHA of the probing host, an SPA of all 0s, a THA of all 0s, and a TPA set to the IPv4 address being probed for. If some host on the network regards the IPv4 address (in the TPA) as its own, it will reply to the probe (via the SHA of the probing host) thus informing the probing host of the address conflict. If instead there is no host which regards the IPv4 address as its own, then there will be no reply. When several such probes have been sent, with slight delays, and none receive replies, it can reasonably be expected that no conflict exists. As the original probe packet contains neither a valid SHA/SPA nor a valid THA/TPA pair, there is no risk of any host using the packet to update its cache with problematic data. Before beginning to use an IPv4 address (whether received from manual configuration, DHCP, or some other means), a host implementing this specification must test to see if the address is already in use, by broadcasting ARP probe packets.<a href="#cite_note-rfc5227-8">[8]</a><a href="#cite_note-9">[9]</a>

<div class="mw-heading mw-heading2"><h2 id="ARP_announcements">ARP announcements</h2></div>

ARP may also be used as a simple announcement protocol. This is useful for updating other hosts' mappings of a hardware address when the sender's IP address or MAC address changes. Such an announcement, also called a gratuitous ARP (GARP) message, is usually broadcast as an ARP request containing the SPA in the target field (TPA=SPA), with THA set to zero. An alternative way is to broadcast an ARP reply with the sender's SHA and SPA duplicated in the target fields (TPA=SPA, THA=SHA).

The ARP request and ARP reply announcements are both standards-based methods,<a href="#cite_note-rfc5944-10">[10]</a>: §4.6 but the ARP request method is preferred.<a href="#cite_note-11">[11]</a>: §3 Some devices may be configured for the use of either of these two types of announcements.<a href="#cite_note-12">[12]</a>

An ARP announcement is not intended to solicit a reply; instead, it updates any cached entries in the ARP tables of other hosts that receive the packet. The operation code in the announcement may be either request or reply; the ARP standard specifies that the opcode is only processed after the ARP table has been updated from the address fields.<a href="#cite_note-13">[13]</a><a href="#cite_note-rfc5944-10">[10]</a>: §4.6 <a href="#cite_note-rfc2131-14">[14]</a>: §4.4.1

Many operating systems issue an ARP announcement during startup. This helps to resolve problems that would otherwise occur if, for example, a <a href="Network_card" class="mw-redirect" title="Network card">network card</a> was recently changed (changing the IP-address-to-MAC-address mapping) and other hosts still have the old mapping in their ARP caches.

ARP announcements are also used by some network interfaces to provide load balancing for incoming traffic. In a <a href="NIC_teaming" class="mw-redirect" title="NIC teaming">team</a> of network cards, it is used to announce a different MAC address within the team that should receive incoming packets.

ARP announcements can be used in the <a href="Zeroconf" class="mw-redirect" title="Zeroconf">Zeroconf</a> protocol to allow automatic assignment of a <a href="Link-local_address" title="Link-local address">link-local address</a> to an interface where no other IP address configuration is available. The announcements are used to ensure an address chosen by a host is not in use by other hosts on the network link.<a href="#cite_note-rfc3927-15">[15]</a>

This function can be dangerous from a cybersecurity viewpoint since an attacker can obtain information about the other hosts of its subnet to save in their ARP cache (<a href="ARP_spoofing" title="ARP spoofing">ARP spoofing</a>) an entry where the attacker MAC is associated, for instance, to the IP of the <a href="Default_gateway" title="Default gateway">default gateway</a>, thus allowing them to <a href="Man-in-the-middle_attack" title="Man-in-the-middle attack">intercept</a> all the traffic to external networks.

<div class="mw-heading mw-heading2"><h2 id="ARP_mediation">ARP mediation</h2></div>

ARP mediation refers to the process of resolving Layer-2 addresses through a <a href="Virtual_private_wire_service" class="mw-redirect" title="Virtual private wire service">virtual private wire service</a> (VPWS) when different resolution protocols are used on the connected circuits, e.g., <a href="Ethernet" title="Ethernet">Ethernet</a> on one end and <a href="Frame_Relay" title="Frame Relay">Frame Relay</a> on the other. In <a href="IPv4" title="IPv4">IPv4</a>, each <a href="Provider_edge" class="mw-redirect" title="Provider edge">provider edge</a> (PE) device discovers the IP address of the locally attached <a href="Customer_edge" class="mw-redirect" title="Customer edge">customer edge</a> (CE) device and distributes that IP address to the corresponding remote PE device. Then each PE device responds to local ARP requests using the IP address of the remote CE device and the hardware address of the local PE device. In <a href="IPv6" title="IPv6">IPv6</a>, each PE device discovers the IP address of both local and remote CE devices and then intercepts local <a href="Neighbor_Discovery" class="mw-redirect" title="Neighbor Discovery">Neighbor Discovery</a> (ND) and <a href="Inverse_Neighbor_Discovery" class="mw-redirect" title="Inverse Neighbor Discovery">Inverse Neighbor Discovery</a> (IND) packets and forwards them to the remote PE device.<a href="#cite_note-16">[16]</a>

<div class="mw-heading mw-heading2"><h2 id="Inverse_ARP_and_Reverse_ARP">Inverse ARP and Reverse ARP</h2></div>

Inverse Address Resolution Protocol (Inverse ARP or InARP) is used to obtain <a href="Network_layer" title="Network layer">network layer</a> addresses (for example, <a href="IP_address" title="IP address">IP addresses</a>) of other nodes from <a href="Data_link_layer" title="Data link layer">data link layer</a> (Layer 2) addresses. Since ARP translates layer-3 addresses to layer-2 addresses, InARP may be described as its inverse. In addition, InARP is implemented as a protocol extension to ARP: it uses the same packet format as ARP, but different operation codes.

InARP is primarily used in <a href="Frame_Relay" title="Frame Relay">Frame Relay</a> (<a href="DLCI" class="mw-redirect" title="DLCI">DLCI</a>) and ATM networks, in which layer-2 addresses of <a href="Virtual_circuit" title="Virtual circuit">virtual circuits</a> are sometimes obtained from layer-2 signaling, and the corresponding layer-3 addresses must be available before those virtual circuits can be used.<a href="#cite_note-rfc2390-17">[17]</a>

The <a href="Reverse_Address_Resolution_Protocol" title="Reverse Address Resolution Protocol">Reverse Address Resolution Protocol</a> (Reverse ARP or RARP), like InARP, translates layer-2 addresses to layer-3 addresses. However, in InARP the requesting station queries the layer-3 address of another node, whereas RARP is used to obtain the layer-3 address of the requesting station itself for address configuration purposes. RARP is obsolete; it was replaced by <a href="BOOTP" class="mw-redirect" title="BOOTP">BOOTP</a>, which was later superseded by the <a href="Dynamic_Host_Configuration_Protocol" title="Dynamic Host Configuration Protocol">Dynamic Host Configuration Protocol</a> (DHCP).<a href="#cite_note-rfc903-18">[18]</a>

<div class="mw-heading mw-heading2"><h2 id="ARP_spoofing_and_proxy_ARP">ARP spoofing and proxy ARP</h2></div>

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</style><div role="note" class="hatnote navigation-not-searchable">Main articles: <a href="ARP_spoofing" title="ARP spoofing">ARP spoofing</a> and <a href="Proxy_ARP" title="Proxy ARP">Proxy ARP</a></div>

Because ARP does not provide methods for authenticating ARP replies on a network, ARP replies can come from systems other than the one with the required Layer 2 address. An ARP proxy is a system that answers the ARP request on behalf of another system for which it will forward traffic, normally as a part of the network's design, such as for a dialup internet service. By contrast, in ARP spoofing the answering system, or spoofer, replies to a request for another system's address with the aim of intercepting data bound for that system. A malicious user may use ARP spoofing to perform a <a href="Man-in-the-middle" class="mw-redirect" title="Man-in-the-middle">man-in-the-middle</a> or <a href="Denial-of-service" class="mw-redirect" title="Denial-of-service">denial-of-service</a> attack on other users on the network. Various software exists to both detect and perform ARP spoofing attacks, though ARP itself does not provide any methods of protection from such attacks.<a href="#cite_note-grc-19">[19]</a>

<div class="mw-heading mw-heading2"><h2 id="Alternatives">Alternatives</h2></div>

IPv6 uses the <a href="Neighbor_Discovery_Protocol" title="Neighbor Discovery Protocol">Neighbor Discovery Protocol</a> and its extensions such as <a href="Secure_Neighbor_Discovery" title="Secure Neighbor Discovery">Secure Neighbor Discovery</a>, rather than ARP.

Computers can maintain lists of known addresses, rather than using an active protocol. In this model, each computer maintains a database of the mapping of <a href="Layer_3" class="mw-redirect" title="Layer 3">Layer 3</a> addresses (e.g., <a href="IP_addresses" class="mw-redirect" title="IP addresses">IP addresses</a>) to <a href="Layer_2" class="mw-redirect" title="Layer 2">Layer 2</a> addresses (e.g., <a href="Ethernet" title="Ethernet">Ethernet</a> <a href="MAC_addresses" class="mw-redirect" title="MAC addresses">MAC addresses</a>). This data is maintained primarily by interpreting ARP packets from the local network link. Thus, it is often called the <a href="ARP_cache" title="ARP cache">ARP cache</a>. Since at least the 1980s,<a href="#cite_note-20">[20]</a> networked computers have a utility called arp for interrogating or manipulating this database.<a href="#cite_note-21">[21]</a><a href="#cite_note-22">[22]</a><a href="#cite_note-23">[23]</a>

Historically, other methods were used to maintain the mapping between addresses, such as static configuration files,<a href="#cite_note-24">[24]</a> or centrally maintained lists.

<div class="mw-heading mw-heading2"><h2 id="ARP_stuffing">ARP stuffing</h2></div>

Embedded systems such as networked cameras<a href="#cite_note-25">[25]</a> and networked power distribution devices,<a href="#cite_note-26">[26]</a> which lack a user interface, can use so-called ARP stuffing to make an initial network connection, although this is a misnomer, as ARP is not involved.

ARP stuffing is accomplished as follows:

<ol><li>The user's computer has an IP address stuffed manually into its address table (normally with the arp command with the MAC address taken from a label on the device)</li>

<li>The computer sends special packets to the device, typically a <a href="Ping_(networking_utility)" title="Ping (networking utility)">ping</a> packet with a non-default size.</li>

<li>The device then adopts this IP address</li>

<li>The user then communicates with it by <a href="Telnet" title="Telnet">telnet</a> or <a href="Http" class="mw-redirect" title="Http">web</a> protocols to complete the configuration.</li></ol>

Such devices typically have a method to disable this process once the device is operating normally, as the capability can make it vulnerable to attack.

<div class="mw-heading mw-heading2"><h2 id="Standards_documents">Standards documents</h2></div>

<ul><li>RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc826">826</a> – <q>An Ethernet Address Resolution Protocol,</q> Internet Standard 37.</li>

<li>RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc903">903</a> – <q>A Reverse Address Resolution Protocol,</q> Internet Standard 38.</li>

<li>RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc2390">2390</a> – <q>Inverse Address Resolution Protocol,</q> Draft Standard.</li>

<li>RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc5227">5227</a> – <q>IPv4 Address Conflict Detection,</q> Proposed Standard.</li></ul>

<ul><li><a href="Arping" title="Arping">Arping</a> – Software utility for discovering and probing hosts on a computer network</li>

<li><a href="Arptables" title="Arptables">Arptables</a> – Network administrator's tool</li>

<li><a href="Arpwatch" title="Arpwatch">Arpwatch</a> – Computer networking software tool</li>

<li><a href="Bonjour_Sleep_Proxy" title="Bonjour Sleep Proxy">Bonjour Sleep Proxy</a> – Open source component of zero configuration networking</li>

<li><a href="Cisco_HDLC" title="Cisco HDLC">Cisco HDLC</a> – Extension to the High-Level Data Link Control (HDLC) network protocol</li></ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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</style><div class="reflist">

<li id="cite_note-IANA-1">^ <a href="#cite_ref-IANA_1-0">a</a> <a href="#cite_ref-IANA_1-1">b</a> <a href="#cite_ref-IANA_1-2">c</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.iana.org/assignments/arp-parameters/arp-parameters.xhtml">"Address Resolution Protocol (ARP) Parameters"</a>. www.iana.org. Retrieved 2018-10-16.</cite>

</li>

<li id="cite_note-rfc9542-2"><a href="#cite_ref-rfc9542_2-0">^</a> <cite id="CITEREFD._Eastlake,_3rdJ._AbleyY._Li2024" class="citation cs1">D. Eastlake, 3rd; J. Abley; Y. Li (April 2024). <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc9542">IANA Considerations and IETF Protocol and Documentation Usage for IEEE 802 Parameters</a>. <a href="Internet_Engineering_Task_Force" title="Internet Engineering Task Force">Internet Engineering Task Force</a>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.17487%2FRFC9542">10.17487/RFC9542</a>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/2070-1721">2070-1721</a>. BCP 141. <a href="Request_for_Comments" title="Request for Comments">RFC</a> <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc9542">9542</a>.</cite> Best Current Practice 141. Obsoletes RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc7042">7042</a>.

</li>

<li id="cite_note-3"><a href="#cite_ref-3">^</a> <cite id="CITEREFDavid_C._Plummer1982" class="citation cs1">David C. Plummer (November 1982). <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc826">An Ethernet Address Resolution Protocol</a>. Network Working Group. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.17487%2FRFC0826">10.17487/RFC0826</a>. STD 37. <a href="Request_for_Comments" title="Request for Comments">RFC</a> <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc826">826</a>.</cite> Internet Standard 37. sec. Network monitoring and debugging. Updated by RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc5227">5227</a> and <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc5494">5494</a>.

</li>

<li id="cite_note-rfc1122-4"><a href="#cite_ref-rfc1122_4-0">^</a> <cite id="CITEREFR._Braden1989" class="citation cs1"><a href="Bob_Braden" title="Bob Braden">R. Braden</a>, ed. (October 1989). <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc1122">Requirements for Internet Hosts -- Communication Layers</a>. Network Working Group. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.17487%2FRFC1122">10.17487/RFC1122</a>. STD 3. <a href="Request_for_Comments" title="Request for Comments">RFC</a> <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc1122">1122</a>.</cite> Internet Standard 3. Updated by RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc1349">1349</a>, <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc4379">4379</a>, <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc5884">5884</a>, <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc6093">6093</a>, <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc6298">6298</a>, <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc6633">6633</a>, <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc6864">6864</a>, <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc8029">8029</a> and <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc9293">9293</a>.

</li>

<li id="cite_note-5"><a href="#cite_ref-5">^</a> W. Richard Stevens, TCP/IP Illustrated, Volume 1: The Protocols, Addison Wesley, 1994, ISBN 0-201-63346-9.

</li>

<li id="cite_note-6"><a href="#cite_ref-6">^</a> W. Richard Stevens, TCP/IP Illustrated, Volume 1: The Protocols, Addison Wesley, 2011, ISBN 0-321-33631-3, page 14

</li>

<li id="cite_note-7"><a href="#cite_ref-7">^</a> <cite id="CITEREFChappellTittel2007" class="citation book cs1">Chappell, Laura A.; Tittel, Ed (2007). Guide to TCP/IP (Third ed.). Thomson Course Technology. pp. 115–116. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>9781418837556</bdi>.</cite>

</li>

<li id="cite_note-rfc5227-8"><a href="#cite_ref-rfc5227_8-0">^</a> <cite id="CITEREFS._Cheshire2008" class="citation cs1"><a href="Stuart_Cheshire" title="Stuart Cheshire">S. Cheshire</a> (July 2008). <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc5227">IPv4 Address Conflict Detection</a>. Network Working Group. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.17487%2FRFC5227">10.17487/RFC5227</a>. <a href="Request_for_Comments" title="Request for Comments">RFC</a> <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc5227">5227</a>.</cite> Proposed Standard. Updates RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc826">826</a>.

</li>

<li id="cite_note-9"><a href="#cite_ref-9">^</a> <cite id="CITEREFHarmoush" class="citation web cs1">Harmoush, Ed. <a rel="nofollow" class="external text" href="https://www.practicalnetworking.net/series/arp/arp-probe-arp-announcement">"ARP Probe and ARP Announcement"</a>. Practical Networking. PracticalNetworking .net. Retrieved 3 August 2022.</cite>

</li>

<li id="cite_note-rfc5944-10">^ <a href="#cite_ref-rfc5944_10-0">a</a> <a href="#cite_ref-rfc5944_10-1">b</a> <cite id="CITEREFC._Perkins2010" class="citation cs1">C. Perkins, ed. (November 2010). <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc5944">IP Mobility Support for IPv4, Revised</a>. <a href="Internet_Engineering_Task_Force" title="Internet Engineering Task Force">Internet Engineering Task Force</a>. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.17487%2FRFC5944">10.17487/RFC5944</a>. <a href="ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/2070-1721">2070-1721</a>. <a href="Request_for_Comments" title="Request for Comments">RFC</a> <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc5944">5944</a>.</cite> Proposed Standard. Obsoletes RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc3344">3344</a>.

</li>

<li id="cite_note-11"><a href="#cite_ref-11">^</a> <cite id="CITEREFS._Cheshire2008" class="citation cs1"><a href="Stuart_Cheshire" title="Stuart Cheshire">S. Cheshire</a> (July 2008). <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc5227">IPv4 Address Conflict Detection</a>. Network Working Group. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.17487%2FRFC5227">10.17487/RFC5227</a>. <a href="Request_for_Comments" title="Request for Comments">RFC</a> <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc5227">5227</a>.</cite> Proposed Standard. Updates RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc826">826</a>. <q>Why Are ARP Announcements Performed Using ARP Request Packets and Not ARP Reply Packets?</q>

</li>

<li id="cite_note-12"><a href="#cite_ref-12">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://support.citrix.com/article/CTX112701">"FAQ: The Firewall Does not Update the Address Resolution Protocol Table"</a>. <a href="Citrix" class="mw-redirect" title="Citrix">Citrix</a>. 2015-01-16. <q>[...] garpReply enabled [...] generates ARP packets that [...] are of OPCODE type REPLY, rather than REQUEST.</q></cite>

</li>

<li id="cite_note-13"><a href="#cite_ref-13">^</a> <cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20071012093401/http://www1.ietf.org/mail-archive/web/dhcwg/current/msg03797.html">"Gratuitous ARP in DHCP vs. IPv4 ACD Draft"</a>. Archived from <a rel="nofollow" class="external text" href="http://www1.ietf.org/mail-archive/web/dhcwg/current/msg03797.html">the original</a> on October 12, 2007.</cite>

</li>

<li id="cite_note-rfc2131-14"><a href="#cite_ref-rfc2131_14-0">^</a> <cite id="CITEREFR._Droms1997" class="citation cs1">R. Droms (March 1997). <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc2131">Dynamic Host Configuration Protocol</a>. <a href="Internet_Engineering_Task_Force" title="Internet Engineering Task Force">IETF</a> Network Working Group. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.17487%2FRFC2131">10.17487/RFC2131</a>. <a href="Request_for_Comments" title="Request for Comments">RFC</a> <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc2131">2131</a>.</cite> Draft Standard. Obsoletes RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc1541">1541</a>. Updated by RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc3396">3396</a>, <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc4361">4361</a>, <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc5494">5494</a> and <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc6842">6842</a>.

</li>

<li id="cite_note-rfc3927-15"><a href="#cite_ref-rfc3927_15-0">^</a> <cite id="CITEREFS._CheshireB._AbobaE._Guttman2005" class="citation cs1"><a href="Stuart_Cheshire" title="Stuart Cheshire">S. Cheshire</a>; B. Aboba; E. Guttman (May 2005). <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc3927">Dynamic Configuration of IPv4 Link-Local Addresses</a>. Network Working Group. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.17487%2FRFC3927">10.17487/RFC3927</a>. <a href="Request_for_Comments" title="Request for Comments">RFC</a> <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc3927">3927</a>.</cite> Proposed Standard.

</li>

<li id="cite_note-16"><a href="#cite_ref-16">^</a> <cite id="CITEREFShah,_H.2012" class="citation cs1">Shah, H.; et al. (June 2012). <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc6575">Address Resolution Protocol (ARP) Mediation for IP Interworking of Layer 2 VPNs</a>. Internet Engineering Task Force. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.17487%2FRFC6575">10.17487/RFC6575</a>. <a href="Request_for_Comments" title="Request for Comments">RFC</a> <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc6575">6575</a>.</cite>

</li>

<li id="cite_note-rfc2390-17"><a href="#cite_ref-rfc2390_17-0">^</a> <cite id="CITEREFT._BradleyC._BrownA._Malis1998" class="citation cs1">T. Bradley; C. Brown; A. Malis (September 1998). <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc2390">Inverse Address Resolution Protocol</a>. Network Working Group. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.17487%2FRFC2390">10.17487/RFC2390</a>. <a href="Request_for_Comments" title="Request for Comments">RFC</a> <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc2390">2390</a>.</cite> Draft Standard. Obsoletes RFC <a rel="nofollow" class="external text" href="https://www.rfc-editor.org/rfc/rfc1293">1293</a>.

</li>

<li id="cite_note-rfc903-18"><a href="#cite_ref-rfc903_18-0">^</a> <cite id="CITEREFR._FinlaysonT._MannJ._MogulM._Theimer1984" class="citation cs1">R. Finlayson; T. Mann; J. Mogul; M. Theimer (June 1984). <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc903">A Reverse Address Resolution Protocol</a>. Network Working Group. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.17487%2FRFC0903">10.17487/RFC0903</a>. STD 38. <a href="Request_for_Comments" title="Request for Comments">RFC</a> <a rel="nofollow" class="external text" href="https://datatracker.ietf.org/doc/html/rfc903">903</a>.</cite> Internet Standard 38.

</li>

<li id="cite_note-grc-19"><a href="#cite_ref-grc_19-0">^</a> <cite id="CITEREFSteve_Gibson2005" class="citation web cs1">Steve Gibson (2005-12-11). <a rel="nofollow" class="external text" href="https://www.grc.com/nat/arp.htm">"ARP Cache Poisoning"</a>. <a href="Gibson_Research_Corporation" class="mw-redirect" title="Gibson Research Corporation">GRC</a>.</cite>

</li>

<li id="cite_note-20"><a href="#cite_ref-20">^</a> <cite id="CITEREFUniversity_of_California,_Berkeley" class="citation web cs1">University of California, Berkeley. <a rel="nofollow" class="external text" href="http://www.freebsd.org/cgi/man.cgi?query=arp&apropos=0&sektion=0&manpath=2.10+BSD&arch=default&format=html">"BSD manual page for arp(8C) command"</a>. Retrieved 2011-09-28.</cite>

</li>

<li id="cite_note-21"><a href="#cite_ref-21">^</a> <cite id="CITEREFCanonical" class="citation web cs1">Canonical. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120316213518/http://manpages.ubuntu.com/manpages/lucid/man8/arp.8.html">"Ubuntu manual page for arp(8) command"</a>. Archived from <a rel="nofollow" class="external text" href="http://manpages.ubuntu.com/manpages/lucid/man8/arp.8.html">the original</a> on 2012-03-16. Retrieved 2011-09-28.</cite>

</li>

<li id="cite_note-22"><a href="#cite_ref-22">^</a> <cite id="CITEREFApple_Computer" class="citation web cs1">Apple Computer. <a rel="nofollow" class="external text" href="https://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man8/arp.8.html">"Mac OS X manual page for arp(8) command"</a>. Retrieved 2011-09-28.</cite>

</li>

<li id="cite_note-23"><a href="#cite_ref-23">^</a> <cite id="CITEREFMicrosoft" class="citation web cs1">Microsoft. <a rel="nofollow" class="external text" href="https://technet.microsoft.com/en-us/library/cc786759%28WS.10%29.aspx">"Windows help for arp command"</a>. Retrieved 2011-09-28.</cite>

</li>

<li id="cite_note-24"><a href="#cite_ref-24">^</a> <cite id="CITEREFSun_Microsystems" class="citation web cs1">Sun Microsystems. <a rel="nofollow" class="external text" href="http://www.freebsd.org/cgi/man.cgi?query=ethers&sektion=5&apropos=0&manpath=SunOS+4.1.3">"SunOS manual page for ethers(5) file"</a>. Retrieved 2011-09-28.</cite>

</li>

<li id="cite_note-25"><a href="#cite_ref-25">^</a> <cite id="CITEREFAxis_Communication" class="citation web cs1">Axis Communication. <a rel="nofollow" class="external text" href="http://www.axis.com/files/manuals/ig_p13Series_38731_en_1006.pdf">"Axis P13 Network Camera Series Installation Guide"</a> (PDF). Retrieved 2011-09-28.</cite>

</li>

<cite id="CITEREFAmerican_Power_Corporation" class="citation web cs1">American Power Corporation. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20111125012617/http://www.apcmedia.com/salestools/ASTE-6Z6K56_R0_EN.pdf">"Switched Rack Power Distribution Unit Installation and Quick Start Manual"</a> (PDF). Archived from <a rel="nofollow" class="external text" href="http://www.apcmedia.com/salestools/ASTE-6Z6K56_R0_EN.pdf">the original</a> (PDF) on 2011-11-25. Retrieved 2011-09-28.</cite>

</li>

</ol></div></div>

<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>

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<div class="side-box-text plainlist">Wikiversity has learning resources about <a href="https://en.wikiversity.org/wiki/Address_Resolution_Protocol" class="extiw external" title="v:Address Resolution Protocol"> Address Resolution Protocol</a></div></div>

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<ul><li><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20210301060206/http://www.eventhelix.com/RealtimeMantra/Networking/Arp.pdf">"ARP Sequence Diagram (pdf)"</a> (PDF). Archived from <a rel="nofollow" class="external text" href="http://www.eventhelix.com/RealtimeMantra/Networking/Arp.pdf">the original</a> (PDF) on 2021-03-01.</cite></li>

<li><a rel="nofollow" class="external text" href="https://wiki.wireshark.org/Gratuitous_ARP">Gratuitous ARP</a></li>

<li><a rel="nofollow" class="external text" href="https://gitlab.com/wireshark/wireshark/-/wikis/AddressResolutionProtocol">Information and sample capture from Wireshark</a></li>

<li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20090903074149/http://sid.rstack.org/arp-sk/">ARP-SK ARP traffic generation tools</a></li></ul>

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</style></div><div role="navigation" class="navbox" aria-labelledby="Internet_Engineering_Task_Force_&#82;FC_standards175" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Internet_Engineering_Task_Force_&#82;FC_standards175" style="font-size:114%;margin:0 4em"><a href="Internet_Engineering_Task_Force" title="Internet Engineering Task Force">Internet Engineering Task Force</a> RFC standards</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Networking protocols</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="User_Datagram_Protocol" title="User Datagram Protocol">User Datagram Protocol</a> (768)</li>

<li><a href="Transmission_Control_Protocol" title="Transmission Control Protocol">Transmission Control Protocol</a> (793)</li>

<li><a href="Telnet" title="Telnet">Telnet</a> (854)</li>

<li><a href="File_Transfer_Protocol" title="File Transfer Protocol">File Transfer Protocol</a> (959)</li>

<li><a href="Domain_Name_System" title="Domain Name System">Domain Name System</a> (1034, 1035)</li>

<li><a href="Gopher_(protocol)" title="Gopher (protocol)">Gopher</a> (1436)</li>

<li><a href="Point-to-Point_Protocol" title="Point-to-Point Protocol">Point-to-Point Protocol</a> (1661)</li>

<li><a href="Post_Office_Protocol" title="Post Office Protocol">Post Office Protocol</a> (1939)</li>

<li><a href="Internet_Message_Access_Protocol" title="Internet Message Access Protocol">Internet Message Access Protocol</a> (3501)</li>

<li><a href="Network_News_Transfer_Protocol" title="Network News Transfer Protocol">Network News Transfer Protocol</a> (3977)</li>

<li><a href="DNSSEC" class="mw-redirect" title="DNSSEC">DNSSEC</a> (4033, etc.)</li>

<li><a href="Secure_Shell" title="Secure Shell">Secure Shell</a> (4251, etc.)</li>

<li><a href="IPsec" title="IPsec">IPsec</a> (4301, etc.)</li>

<li><a href="Datagram_Congestion_Control_Protocol" title="Datagram Congestion Control Protocol">Datagram Congestion Control Protocol</a> (4340)</li>

<li><a href="Lightweight_Directory_Access_Protocol" title="Lightweight Directory Access Protocol">Lightweight Directory Access Protocol</a> (4510, etc.)</li>

<li><a href="Stream_Control_Transmission_Protocol" title="Stream Control Transmission Protocol">Stream Control Transmission Protocol</a> (4960)</li>

<li><a href="Network_Time_Protocol" title="Network Time Protocol">Network Time Protocol</a> (5905)</li>

<li><a href="Hypertext_Transfer_Protocol" class="mw-redirect" title="Hypertext Transfer Protocol">Hypertext Transfer Protocol</a> (7230-7235)</li>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Data formats</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Portable_Network_Graphics" class="mw-redirect" title="Portable Network Graphics">Portable Network Graphics</a> (2083)</li>

<li><a href="Uniform_resource_identifier" class="mw-redirect" title="Uniform resource identifier">Uniform resource identifier</a> (3986)</li>

<li><a href="ICalendar" title="ICalendar">iCalendar</a> (5545)</li>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="April_Fools'_Day_Request_for_Comments" title="April Fools' Day Request for Comments">April Fools' Day RFC</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="IP_over_Avian_Carriers" title="IP over Avian Carriers">IP over Avian Carriers</a> (1149)</li>

<li><a href="Hyper_Text_Coffee_Pot_Control_Protocol" title="Hyper Text Coffee Pot Control Protocol">HTCPCP</a> (2324)</li>

<li><a href="Semaphore_Flag_Signaling_System" title="Semaphore Flag Signaling System">Semaphore Flag Signaling System</a> (4824)</li></ul>

</div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div>Category:Internet Standards</div></td></tr></tbody></table></div></div><div><div class="zim-footer">

This article is issued from <a class="external text" title="Last edited on 2025-04-29" href="https://en.wikipedia.org/wiki/?title=Address_Resolution_Protocol&oldid=1287902857">Wikipedia</a>. The text is available under <a class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">Creative Commons Attribution-Share Alike 4.0</a> unless otherwise noted. Additional terms may apply for the media files.

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