Why do we need IP address when the MAC address is unique? Can't we communicate only with MAC address?

Showing Answers 1 - 24 of 24 Answers


  • Apr 16th, 2007

MAC address is the basis on which communication occurs.However we need IP  address to be able to create a routing table ,that enables faster  commnication.Lots of communication algorithms take use of IP address ( Network address +SubNet masks) to be able to route packages faster.


  • Sep 19th, 2007

We need I.P address because when we work on LAN we can communicate without I.P address with the help of NETBIOS and WINS but in WAN we work on network layer and data frame becomes packet and packet need I.P address for routing

  Was this answer useful?  Yes

The actual answer is:-

Ip address(network address) is just use for transfering informatiom from one network to an other.travelling of information among networks uses ip addresses.

Mac addresses(physical addresses) is actually uses for distrubution of information.so, the summay is:-

1) carring of information from one network to another.
2) distrubtion of information(resources) is based upon mac address.

Network A , Network B and Network C are three networks.all network are having 5 nodes(client).if i want to send information to node 3 for network B.

1) first i send infomation to network by the help of IP address of that network(Network B).Ip addresses are unique on network layer(this is the fact).  

2)after that i will send infomation to node 3 of network B by the help of mac address which is unique at layer 2(DLL).


  • May 20th, 2008

IP address (network address) is just used for transferring information from one network to another network. Travelling of information among networks uses IP addresses. It is used to identity the network and host.

A MAC address (physical addresses) is used for distribution of information with in the network segment. The Ethernet uses MAC address to transfer data between hosts. When its used with IP network, the IP address is resolved using ARP protocol to find the MAC address of the end device and the data is transmitted.

Port numbers are used by the TCP/UDP protocol to isolate the traffic which is multiplexed and sent by the user application. For example, the user device, can open multiple applications at the same time like, multiple web browsers, email and FTP. To identify the data individually the port number are used.

  Was this answer useful?  Yes


  • Jul 24th, 2009

IP address is used to identify uniquely the device.

MAC is used to identify the node and to find the next hop address.

  Was this answer useful?  Yes


  • Jun 17th, 2010

The answer is that the IP Address is at the "Software or Logical level, and helps to establish communication between 2 or more Networks at the OSI (Network Level), whereas the MAC Address is at the OSI (Data Link Layer), which has the Physical Address of the actual node (machine). Final Data Distribution (Information Transfer) from the Network Segments (originally PAckets at the Transport Layer) to the Destination Client Node must work at he PHYSICAL LEVEL which starts at the DATA LINK LAYER.

The final Layer in the OSI model (Physical Layer) then translates the MAC ADDRESS to the actual WIRES (RJ45) etc. which work at the ELECTRONS LEVELS.

ONLY MAC ADDRESSES and NO IP ADDRESS will not work. Software at the TRANSPORT LAYER (TCP and IP) does not support physical addresses.

  Was this answer useful?  Yes

For layer2 of networking, i.e. the Media Access Control layer, Ethernet address or MAC address is unique.

For layer3 of networking, i.e. the Network Layer, IP address is unique.

For a network segment, e.g. LAN , we can communicate with help of NETBIOS and WINS.
But we need IP address for WAN. In WAN we see different requirement like to follow ROUTING ALGORITHM , SUBNET MASK etc......these are impossible by MAC addresss.

  Was this answer useful?  Yes

Syed Zeeshan

  • Nov 16th, 2011

Ip address is just used for transferring information from one Network to another Network.It will just transfer the information from one network to another.

Whereas,the Mac Address is actually responsible for distributing that information to actual Host in the Network.

  Was this answer useful?  Yes


  • Nov 18th, 2011

the function of mac address and ip address different mac address is physical address which is not work on Internet. but ip address is used to communicate with in world. no we cannot communicate only with mac address because this is physical address and communication possible on logical address.

  Was this answer useful?  Yes


  • Mar 4th, 2012

the answer would be our ip address determines our location........if we use a mac instead then we have to search the whole internet to forward a packet, this would flood the network. The advantage of ip is that it is divided on region basis and to forward a packet we have a path to follow

IP address is a logical arrangement whereas a mac is not a logical arrangement.......its random

it is easy to trace down a station with an ip coz its divided according to region whereas in mac it is not possible.

  Was this answer useful?  Yes

Ibrahim Kay

  • Jun 8th, 2012

Consider this: What if there was no IPs? Can every computer in the world ARP every other computer in the world? Can indefinite numbers of switches be connected/trunked together between New York, California, and Burma too? Say you did this smartly, with a hub-spoke topology, how many MAC entries would the ports on those central switches actually have? MAC addresses are quite random, each switch would have to memorize every single last MAC of every device reachable on every port on a global scale in order for packet switching to operate..

UNLESSSSSSS, you developed a way to logically assign MAC addresses, where your MAC would fall into a subnet and your LAN would all share the same MAC address beginning but have logically assigned bits at the end, that way switches don't need EVERY MAC, they just need your network MAC and then your local switch handles the rest.

That would do fine, and that right there is precisely what IP addresses do.

Only problem is, if you don't have a physical address hard-coded, then how can the machine ever use DHCP?

Your next question might be, yeah but isn't the 48-bit MAC address a little more scalable than the 32-bit IP add?

Sure but that's why they are working on IPv6, which is more scalable than even that.

I feel that this is what you meant in your question, I hope that helped.

  Was this answer useful?  Yes

Emre Yilmaz

  • Sep 18th, 2012

Ibrahim Kay has a good approach for the solution but there is a missing thing. If we could see the future in those days or had required things like high bandwidth and lots of equipment that connected to internet at that time maybe vendors could build special MAC for this problem.

Some bits of it maybe expresses states or some regions. Furthermore Ethernet is not only one layer 2 protocol.. there is also Frame Relay, ATM etc. For example think of vpi/vci logic, why do we represent vpi with only 8/12 bits or 16 bits for vci?

Couldnt be much more? What is the behind of that logic?

Because all of the requirements is enough at that time. On the other hand different communities develop different technologies such as Ethernet, ATM, Frame/Relay, etc. But all of them are solutions for local area network and it is enough in those days. Then networking burst, spread to wide areas and people need much more end points and also they need to integrates different technologies into one logical network layer which is called Network layer or OSI layer 3 now.

  Was this answer useful?  Yes


  • Sep 26th, 2012

Mac address are layer 2, while IP address is layer 3 that is required for TCP/IP to work, which is the basis on data traffic.

  Was this answer useful?  Yes


  • Dec 22nd, 2012

Technology has divided into two part Hardware part and Software part,
When we insert the LAN card or NIC card into computer,our hardware part is ready,when we installed driver to it our software part is ready,but for proper communication there must be binding between IP Address and MAC Address this binding is stored in ARP table,technology uses a mac address FOR COMMUNICATION Upper layer uses a IP Address.

  Was this answer useful?  Yes


  • Dec 22nd, 2012

MAC address is the physical address of computer. It can not change. But Ip address can change if we want.
By using ip address , we can ping from more than one computer to one computer and get reply.
Example: first pc ip
second pc ip
Third pc ip

If we ping from & from to at a time, able to give reply to both &

This is not possible in case of Only MAC address

  Was this answer useful?  Yes


  • Mar 9th, 2016

Short answer: We use IP address because of (Distance).
The explanation: To meet a person, you have to be both in same location
// Logically//
at the same logical system or standard. If there is no distance the meeting is direct but in case of distance there must be //route//, a way to get to the other location.

The physical location: MAC address
The logical route: IP address

  Was this answer useful?  Yes


  • Oct 20th, 2016

Technology has two part hardware part and software part, when we install LAN card, our hardware part is ready and we install a driver and our software part is ready, but while communication upper layer protocol uses the IP address. It is just like agent and technology uses the mac address, there is binding between mac address and IP address into the ARP table.

  Was this answer useful?  Yes


  • Nov 16th, 2016

so we can communicate through IP address itself why weed need of MAC address?

  Was this answer useful?  Yes

Ganesh Rathore

  • Jan 4th, 2017

MAC is used for layer-2 segregation and IP is used for Layer-3 segregation.

Layer-3 is Network layer on which all our communication is done, so we need a IP address for Layer-3 for unique identification.

  Was this answer useful?  Yes


  • Jan 10th, 2017

Since Mac address does not include any type of routing information. Since NIC contains the Vendor ID, date and serial number which is not needed for routing.

  Was this answer useful?  Yes


  • Nov 28th, 2017

If the packets comes to router of the network to which host is connected, we can send packet to destination host as we know destination IP address(unique). So why do we need MAC address?

  Was this answer useful?  Yes

Give your answer:

If you think the above answer is not correct, Please select a reason and add your answer below.


Related Answered Questions


Related Open Questions