Difference between ARP and RARP

ARP and RARP protocols are the main forms of LAN (Local Area Network) protocols. When a transmitter transfers an IP datagram from one host to another host, it necessities both the logical and physical addresses of the receiver. The dynamic mapping protocol supports two protocols: ARP protocol and RARP protocol. The primary distinction between these ARP and RARP protocols is that the ARP protocol acquires the receiver's physical address when given the receiver's logical address. In contrast, the RARP protocol obtains the host's logical address from the server when given the physical address of the host.

In this article, you will learn about the difference between ARP and RARP Protocols. But before discussing the differences, you must know about ARP and RARP Protocols with their advantages and disadvantages.

What is ARP?

ARP is commonly "Address Resolution Protocol". It is a form of network layer protocol. As the ARP protocol is a dynamic mapping protocol, every host on the network is aware of another logical address of the host server. If the host requires transferring an IP datagram to another host, the IP datagram must be enclosed into a frame. It must be accomplished in such a manner that the datagram may easily flow across the physical network that exists between the receiver and the transmitter.

Advantages and Disadvantages of ARP

There are various advantages and disadvantages of ARP. Some main advantages and disadvantages of ARP are as follows:

Advantages

1. The primary purpose of this protocol is to enable any computer system on a network to enhance a mapping between two addresses, including IP and physical.
2. If you know the IP address of the same system, you may utilize an ARP protocol to determine the MAC address.
3. The set of mappings saved on the host is referred to as the ARP cache/table.
4. End nodes should not be arranged in such a way that they may detect MAC addresses. It may be found when needed.

Disadvantages

1. ARP Spoofing is a technique that an attacker mainly utilizes to gain access to an Ethernet network. It can result in data frame snooping on switched LAN networks, or the attacker can terminate overall traffic, commonly known as ARP denial of service.
2. ARP attacks may occur, including ARP spoofing and Denial of Service.

What is RARP?

RARP is commonly known as a "Reverse Address Resolution Protocol". The RARP protocol is also a type of network layer protocol. A TCP/IP protocol enables any host to get its true IP address from the network server. As the name defines, the RARP protocol is an extended version of the ARP. It is usually the opposite of the ARP protocol.

Advantages and Disadvantages of RARP

There are various advantages and disadvantages of RARP. Some main advantages and disadvantages of RARP are as follows:

Advantages

1. It is a network access layer protocol that is utilized to transfer data between two sites in a network.
2. It is utilized to convert an Ethernet address to an IP address.
3. It is accessible for LAN technologies such as FDDI, token ring LANs, and many others.

Disadvantages

1. It can't handle the subnetting operation since no network masks are transferred. If the network is categorized into subnets, every subnet must have its own RARP server.
2. It should be placed on the same physical network as the client.
3. It does not fully exploit the capability of a network such as Ethernet.
4. The computer transfers the RARP protocol request through a low-cost network layer. As a result, a router cannot forward the packet since the computer system makes the RARP request on a relatively low layer of the network.
5. In a modern network, setting up a computer system is impossible.

Key differences between ARP and RARP Protocol

There are various key differences between ARP and RARP Protocols. Some of the key differences between ARP and RARP Protocols are as follows:

1. The ARP protocol obtains the receiver's physical address. In contrast, the RARP protocol obtains the protocol's logical (IP) address.
2. ARP protocol translates a 32-bit logical (IPv4) address to a receiver's 48-bit physical address. In contrast, the RARP protocol transfers the receiver's 48-bit physical address to its 32-bit logical address.
3. ARP protocol is utilized by the router or host to determine the address (physical address) of another router/host in the LAN network. In contrast, the RARP protocol is operated by small clients with low resources.
4. The local host manages or handles the ARP protocol table. In contrast, the RARP server administers or handles the RARP protocol table.
5. ARP protocol is utilized by hosts and routers to determine the other host's and router's MAC addresses in the network. In contrast, the RARP protocol is utilized by small users with limited facilities.
6. The ARP protocol reply is mostly utilized to update or modify the ARP table. In contrast, the RARP protocol reply is primarily utilized to set the local host's IP address.
7. The client broadcasts its IP address and asks for a MAC address through ARP protocol, and the server answers with the associated MAC address. In contrast, in the RARP protocol, the client broadcasts its MAC address and asks for an IP address, and the server answers with the associated IP address.
8. The ARP protocol utilizes the value 1 for requests or asks and the value 2 for answers. In contrast, the RARP protocol utilizes the value 3 for requests or asks and the value 4 for answers.

Head-to-head comparison between ARP and RARP Protocol

Here, you will learn head-to-head comparisons between ARP and RARP Protocol. The main differences between ARP and RARP Protocol are as follows:

Conclusion

ARP and RARP protocols share some commonalities and differences, such as how they map the Machine address and the Internet Protocol. The node employs RARP unicast and ARP broadcast for data transmission in the LAN network. Both protocols are included in the network layer, the third layer of the Open Source Interconnection (OSI) paradigm.