Wonderful video, it is so clear and helpful. can u clarify this doubt for me, if Apple phones could call to apple phones only, no one would probably buy apple phone, so how apple phones to android phones, the calls get connected can u explain with respect to OSI model please?
1) if there is something in apple(which i am not aware of) where only apple phonecan communicate with apple phone only . Then this would be completely based on software feature specific to apple and they might have used mac based(OUI) filter for that. To answer your second question, every call is just processed like any other networking packets do. Here when someone calls ,the data packet reaches another receiver(phone) over antenna then the signal is converted to digital data and packet is stored in a buffer (this happens at layer 1 ,physical layer) .the the buffer goes to mac layer i.e. layer 2(inside kernel), this layer has proprietory code meant to parse and do specific operations only meant for call datas , here the ethernet header is added(so that information can pass through internet after this layer). Then that data is passed over to layer 3 i.e network layer network .(either here or in layer 2 , decision is taken whether to forward the call data or it is meant for this device) and if forwarding is need no other operation is needed ,it will just pass it down the stack over to internet else it will go up to layer 4 (here kernel layer ends) and then to userspace application for consumption. I hope it gives you little clarification. Thanks for visiting Canny Information Center
At time 2:22 you mention MAC needs to change from hop to hop. I am not clear why. What would happen if there was no MAC address at all? Say, hostA sends the packet for hostB in the different network. If gateway or router does not know how to route to this IP, it sends it up to the upper level, until at some point the router knows where to send this packet. In the end, ARP protocol is basically based on IP is requesting for MAC address. The question is if the ARP packet was able to get to the host based on IP, why would hostA not send the data packet based on the same IP?
To answer this i will give an example , your home address = ip address and your id is your mac, and your local postoffice address is your nearest mac , for example someone send a courier to you , what happens ,does the postman know where you are based on your home address (no). He will send to his nearest postoffice(mac), they will then forward to another post office (another mac) then going through different mac it finally reaches you. I hope this example explains your doubt
@@cannyinformationcenter8236 thanks for the response. Well, it does not fully address my question. You brought an example on postman, but I am not convinced this is well associated with tcp packet transfer. The postman delivers the parcel to postoffice, not because he cannot find me, but to split the responsibilities: he will deliver thousands of parsels to postoffice and then postoffice will distribute them to addressees. Postoffice does not add any new address to envelope after receiving it, so in theory it could have been delivered straight to the address. Same question is for IP protocol. ARP packet gets delivered to a host using IP address only, without MAC, that means it is possible. Why not to leave MAC address empty always and deliver data like ARP? Does my question make any sense?
This is a circular reasoning explanation. The ip address is used to locate a specific device within a network. (at this point why would another identifier be necessary?) Then the mac address is used to identify the specific device to deliver the information. This is circular. What is the specific purpose of the mac address in data delivery when all you need to identify the destination of the data is the IP?
Thanks for for your reply , first of all ip is not used to locate a device within a network, rather it can be within or out side of network. Secondly if its outside of network then how the sender knows where it is ? Here comes mac i.e. sender will use mac of the next known gateway until it reaches the destination where as ip will remain as destition ip. Another point is ip is not constant to a particular device but mac is .i hope it brings you some more clarity
This was a great explanation and a good first video! Make more please!!
Wow I was just looking for this answer. You cleared the concept with ease man.
This video is insane man. Top class presentation.
Wow you just opened my eyes. You just cleared all my doubts.
I Thank you very much Abdulelah for carving out some time to comment and keep us motivated to create meaningful resources .
Nice video , keep it up
very clear explanation ....
thanks man!!!!!!!!!!!!!!!!!!
Wonderful video, it is so clear and helpful. can u clarify this doubt for me, if Apple phones could call to apple phones only, no one would probably buy apple phone, so how apple phones to android phones, the calls get connected can u explain with respect to OSI model please?
1) if there is something in apple(which i am not aware of) where only apple phonecan communicate with apple phone only . Then this would be completely based on software feature specific to apple and they might have used mac based(OUI) filter for that.
To answer your second question, every call is just processed like any other networking packets do. Here when someone calls ,the data packet reaches another receiver(phone) over antenna then the signal is converted to digital data and packet is stored in a buffer (this happens at layer 1 ,physical layer) .the the buffer goes to mac layer i.e. layer 2(inside kernel), this layer has proprietory code meant to parse and do specific operations only meant for call datas , here the ethernet header is added(so that information can pass through internet after this layer). Then that data is passed over to layer 3 i.e network layer network .(either here or in layer 2 , decision is taken whether to forward the call data or it is meant for this device) and if forwarding is need no other operation is needed ,it will just pass it down the stack over to internet else it will go up to layer 4 (here kernel layer ends) and then to userspace application for consumption. I hope it gives you little clarification. Thanks for visiting Canny Information Center
At time 2:22 you mention MAC needs to change from hop to hop. I am not clear why. What would happen if there was no MAC address at all? Say, hostA sends the packet for hostB in the different network. If gateway or router does not know how to route to this IP, it sends it up to the upper level, until at some point the router knows where to send this packet. In the end, ARP protocol is basically based on IP is requesting for MAC address. The question is if the ARP packet was able to get to the host based on IP, why would hostA not send the data packet based on the same IP?
To answer this i will give an example , your home address = ip address and your id is your mac, and your local postoffice address is your nearest mac , for example someone send a courier to you , what happens ,does the postman know where you are based on your home address (no). He will send to his nearest postoffice(mac), they will then forward to another post office (another mac) then going through different mac it finally reaches you. I hope this example explains your doubt
@@cannyinformationcenter8236 thanks for the response. Well, it does not fully address my question. You brought an example on postman, but I am not convinced this is well associated with tcp packet transfer. The postman delivers the parcel to postoffice, not because he cannot find me, but to split the responsibilities: he will deliver thousands of parsels to postoffice and then postoffice will distribute them to addressees. Postoffice does not add any new address to envelope after receiving it, so in theory it could have been delivered straight to the address. Same question is for IP protocol. ARP packet gets delivered to a host using IP address only, without MAC, that means it is possible. Why not to leave MAC address empty always and deliver data like ARP? Does my question make any sense?
This is a circular reasoning explanation.
The ip address is used to locate a specific device within a network. (at this point why would another identifier be necessary?) Then the mac address is used to identify the specific device to deliver the information. This is circular.
What is the specific purpose of the mac address in data delivery when all you need to identify the destination of the data is the IP?
Thanks for for your reply , first of all ip is not used to locate a device within a network, rather it can be within or out side of network. Secondly if its outside of network then how the sender knows where it is ? Here comes mac i.e. sender will use mac of the next known gateway until it reaches the destination where as ip will remain as destition ip. Another point is ip is not constant to a particular device but mac is .i hope it brings you some more clarity