ARP is protocol that doesn't fit nicely into the OSI model. It's not a layer two protocol because it utilizes Ethernet_II (Data Link) to get around with broadcast addresses (FF:FF:FF:FF:FF:FF). It's also not a layer three protocol because it doesn't provide routing capabilities. It maps layer 2 addresses to corresponding layer 3 addresses. So you could say it's 2.5. It is encapsulated within Ethernet_II frames.
Layer 3 of the OSI model
ARP is a Third layer or Network layer protocol. ARP is an address resolution protocol . The mechanism used by ARP to resolve IP address is look up table.
ARP and RARP protocols are present at network layer. ARP is short form of address resolution protocol. IP is the type of header an ARP frame contain .
Routers operate at layer 3. LAN switches operate at layer 2. Ethernet hubs operate at layer 1.
ARP is used to find a MAC (layer-2) address, if you know the IP (layer-3) address.First, a device will search its ARP cache, to see whether it already happens to have the required address. If it doesn't find the address, it will send an ARP request as a broadcast, which basically asks "Who has such-and-such an IP address?" The machine that has the requested IP address will send an ARP reply.
To make ARP more efficient computers save recognized mac to IP address mappings on their hard disks in a database known as ARP cache. ARP is an network layer protocol / third layer protocol. ARP provides mapping between Logical to physical address.
static gateway address
Bridge operate on data link layer
The purpose of an arp request is to map an IP address to a MAC address for the link layer to transmit a packet. For example, ARP will get a request to map 1.2.3.4 to a MAC address 12:fd:23:gf .Then ARP will cache the address mapping that next time an arp request doesnt need to happen
Hubs are a physical layer (layer 1) device; most switches operate at the Data Link layer (Layer 2) of the OSI model.
Reverse ARP is used to Obtain IP address from a Server(responsible for IP addresses allocation) by providing its layer 2 (MAC) address.
ARP
In theory, no, not necessarily, since ARP is flexible enough to be used to discover or describe a connection between other kinds of addresses, which donβt have to be the same lengths as IPv4 and Ethernet addresses.