TCP/IP and Ethernet are both protocols used in computer networking, but they serve different functions. I don't understand their specific use in real world application

Suppose we have smart home automation system. Various smart devices (e.g. smart lights, thermostats, cameras) are connected to a central controller, such as a Raspberry Pi or an Arduino board.

For example, if a user wants to turn on a smart light, they can use a smartphone app to send a command to the central controller. The controller then send a message to the smart light instructing it to turn on.

Which protocol (TCP/IP or Ethernet ) would be use to turn on smart light?

 

https://us.profinet.com/ethernet-is-not-a-protocol/


Ethernet is really a physical interface. In the very old days we used thick coax cable with vampire taps at the marked 'nodes' as the physical interface.
https://en.wikipedia.org/wiki/10BASE5

Other physical interfaces can be used for TCP/IP like wireless or old stuff like this:
https://en.wikipedia.org/wiki/Serial_Line_Internet_Protocol

For smart home automation system 'Matter' is trying to be the next 'standard'.
https://matter-smarthome.de/en/matter-faq-en/

 

Possibly one or the other, both, or neither. Depends on the specifics.

 

https://us.profinet.com/ethernet-is-not-a-protocol/

View attachment 288137
Ethernet is really a physical interface. In the very old days we used thick coax cable with vampire taps at the marked 'nodes' as the physical interface.
https://en.wikipedia.org/wiki/10BASE5

I disagree. A protocol is nothing more than a set of rules that people agree to follow in order to accomplish some task. The Ethernet standards encompass both physical specifications and protocol specifications. The physical specifications cover the things like physical media and signaling mechanisms while the protocol specifications cover such things as frame structure, synchronization, and error detection/correction.

 

I disagree. A protocol is nothing more than a set of rules that people agree to follow in order to accomplish some task. The Ethernet standards encompass both physical specifications and protocol specifications. The physical specifications cover the things like physical media and signaling mechanisms while the protocol specifications cover such things as frame structure, synchronization, and error detection/correction.

I mean it's not a protocol like RS-232 is not a upper layer Protocol. You can call things anything you want but it does matter when you build things. Ethernet is not specific for TCP/IP, it's totally agnostic to the upper layers much like CANBUS is.

I agree that modern Ethernet implementations have blurred the ISO networking structure a bit to overlap what Ethernet means in terms of applications.

 

Possibly one or the other, both, or neither. Depends on the specifics.

Suppose we have a reader EM18 which is placed on the door and connected to 8051(AT89C51) microcontroller. Relay is connected to the 8051 to open or close the door gate.

When a person places the card in front of the reader, the reader scans it and sends it to the 8051. Microcontroller compares the card number with the stored number in program if it is valid then gives it access to the gate. If the card is invalid then it does not get access to the gate.

In this way this system will be installed at all the gates of an office.

suppose we have installed the many system at different city locations and i want to control this whole system with central controller.

In this condition, how can we monitor each of systems from the central controller?

Which protocol (TCP/IP or Ethernet ) would be use to monitor access and attendance?

 

Suppose we have a reader EM18 which is placed on the door and connected to 8051(AT89C51) microcontroller. Relay is connected to the 8051 to open or close the door gate.

When a person places the card in front of the reader, the reader scans it and sends it to the 8051. Microcontroller compares the card number with the stored number in program if it is valid then gives it access to the gate. If the card is invalid then it does not get access to the gate.

In this way this system will be installed at all the gates of an office.

suppose we have installed the many system at different city locations and i want to control this whole system with central controller.

In this condition, how can we monitor each of systems from the central controller?

Which protocol (TCP/IP or Ethernet ) would be use to monitor access and attendance?

The I/O door/reader controller data exchange would be running at the application layer area in the classic ISO network stack. TCP/IP with Ethernet is part of a traditional network or a general network connection fabric that a central controller application could use to talk to the door/reader controller application directly if each local system used networking functionality similar to this.
https://forum.allaboutcircuits.com/...nd-sensor-node-for-canbus.189388/post-1795532

 

central controller application could use to talk to the door/reader controller application directly if each local system used networking functionality

Suppose my head office is in Washington DC and office location A has five systems installed and office location B has ten systems installed and office location C has twenty systems installed.

Should all the systems installed in an office be connected on a network for which ethernet port and ethernet protocol will be used?

 

Yes, or WiFi or optical fiber or any other physical layer. You do not seem to be getting it that both the internet protocol and the physical transport layer are required for an internet connection.

 

Suppose we have a reader EM18 which is placed on the door and connected to 8051(AT89C51) microcontroller. Relay is connected to the 8051 to open or close the door gate.

When a person places the card in front of the reader, the reader scans it and sends it to the 8051. Microcontroller compares the card number with the stored number in program if it is valid then gives it access to the gate. If the card is invalid then it does not get access to the gate.

In this way this system will be installed at all the gates of an office.

suppose we have installed the many system at different city locations and i want to control this whole system with central controller.

In this condition, how can we monitor each of systems from the central controller?

Which protocol (TCP/IP or Ethernet ) would be use to monitor access and attendance?

You are trying to confuse very different things. The main part of your goal -- having doors talk to central offices -- is an application-layer discussion. TCP/IP and Ethernet (and it is NOT an either/or proposition -- these are not alternatives, but rather different things that operate at different levels of the communications stack) are much lower layer issues.

One of the central concepts of the communications stack is that each layer provides services to the layer above it in such a way that the higher layers neither know nor care how those services are provided.

Just like when you drop a package off at a shipping company to be delivered to another country. All you know or care about is that your package will be delivered within a certain set of specifications such as time and cost. You may have know idea whether it is going by air or ground or whether a single company will transport it the entire way or whether it will be carried by multiple carriers along the way. Those are issues that are handled by the shipper in a manner transparent to you.

 

What's why it's important IMO to make a distinction between networking protocols and the physical transport layer. In the 80's/90's, before the Internet moved almost everything to TCP/IP, internal to each office any one of many protocols could be used on the same physical transport layer hardware with a gateway to the public/private network. XNS, DECnet, Apple's AppleTalk (EtherTalk), Novell's IPX, Banyan VINES, NetBEUI, DLC/LLC, IBM SNA, etc ... Today it might be 'Matter'. Things like IP Addresses are software abtractions for internetworking , while a MAC address is hardware for local transport frame packets.

 

Suppose my head office is in Washington DC and office location A has five systems installed and office location B has ten systems installed and office location C has twenty systems installed.

Should all the systems installed in an office be connected on a network for which ethernet port and ethernet protocol will be used?

There is nothing that says that Ethernet has to be used at all. There is nothing that says that if Office A uses Ethernet that Office B then has to. There is nothing that says that if five of the systems in Office C use Ethernet that the other fifteen can't use something else.

I currently have three printers in my home office. One is connected to the network via ethernet. One is connected via WiFi. The third is connected indirectly by being shared from a computer to which it is attached via USB.

If I wanted to (and I don't), I could make any of those printers accessible to me from anywhere in the world over the Internet by using an application-layer utility. That utility would neither know nor care how each of those printers was connected to the network, merely that they are available on the network.

 

There is nothing that says that Ethernet has to be used at all. There is nothing that says that if Office A uses Ethernet that Office B then has to. There is nothing that says that if five of the systems in Office C use Ethernet that the other fifteen can't use something else.

I provided an example in which I think Ethernet and TCP/IP can be used in door access system.

The employee id and name of all the employees are stored in a company's servers database. Access system installed at each sub branch of the company. At each door the employee ID is matched with the ID stored in the database, if it is stored in the database it will be considered a valid employee. It will be decided from the central server that which employee will have access to which door. As the marketing person will have access to the marketing department only, he cannot go to the accounts department.


Can Ethernet and TCP/IP be used in above system? if yes , how?

 

I provided an example in which I think Ethernet and TCP/IP can be used in door access system.

The employee id and name of all the employees are stored in a company's servers database. Access system installed at each sub branch of the company. At each door the employee ID is matched with the ID stored in the database, if it is stored in the database it will be considered a valid employee. It will be decided from the central server that which employee will have access to which door. As the marketing person will have access to the marketing department only, he cannot go to the accounts department.


Can Ethernet and TCP/IP be used in above system? if yes , how?

If a company evaluating this for a possible installation job said, no, Ethernet and TCP/IP can't be used, what would be your response?

 

I provided an example in which I think Ethernet and TCP/IP can be used in door access system.

The employee id and name of all the employees are stored in a company's servers database. Access system installed at each sub branch of the company. At each door the employee ID is matched with the ID stored in the database, if it is stored in the database it will be considered a valid employee. It will be decided from the central server that which employee will have access to which door. As the marketing person will have access to the marketing department only, he cannot go to the accounts department.


Can Ethernet and TCP/IP be used in above system? if yes , how?

You insist on mixing apples and oranges.

It's like someone asking whether or not leather seats can be used in a car that has power brakes and, if so, how.

Ethernet is nothing more than a way of providing a low-level communications link between devices. Whether you use it or don't use it is completely independent of anything related to doors and card readers and servers and databases.

The same for TCP/IP.

Today, there's a good chance that both of these are going to be used for a significant fraction of the journey between devices, but that's not at all required and the software that is dealing with doors and databases and account access restrictions is completely separate and independent from this.

 

Which protocol (TCP/IP or Ethernet )

Can Ethernet and TCP/IP be used

You’ve made an important destination between these two posts. Ethernet and TCP/IP is the proper wording. So the answer to if they can be used is “Yes”.

But, you have two remaining considerations. What are you going to use for the application layer? And how are you going to route the messages.

Taking the latter question first, for a remote device to be able to talk to a central server, each end must be able to reach the other’s. This can be done by having a public IP address. IP addresses can be public or private. Private addresses are used on a local area network. Public IP addresses are used for devices that are accessed via the Internet.

Other considerations are firewall and/or router configurations to allow messages to route between a local area LAN and the Internet. It is possible, but difficult, to connect a device directly to the Internet, but it would have to contain router code+.

As far as the application layer, HTTP and MQTT are such protocols. There are many others.

So, you could communicate with Ethernet and TCP/IP… but there is more to solve your problem.

 

Plus, there's no need to use the Internet at all. It could be done via satellite links or using the mobile phone network (though either might use the Internet internally, which underscores the point that the two discussions are independent).

 

If a company evaluating this for a possible installation job said, no, Ethernet and TCP/IP can't be used, what would be your response?

The central server cannot connect to the each door without Ethernet and TCP/IP. If the server has to communicate with every single door it has to use Ethernet and TCP/IP

 

The central server cannot connect to the each door without Ethernet and TCP/IP. If the server has to communicate with every single door it has to use Ethernet and TCP/IP

Let's take a look at a typical RFID reader and interfaces.
https://www.rfidinc.com/lf-125-khz-rfid-smart-interfaces-for-r3-2-systems

Our Model 8000-SI Series RFID Smart Interfaces are single piece Reader, Interface & Antenna with the PLC communication protocols of Ethernet/IP, DeviceNet, PROFINET, Profibus, Modbus RTU, Modbus TCP, as well as standard TCPIP Ethernet and serial communications. CanOpen available as well.

There are places (Head-end system to Control Panels) in your reader/database network were TCPIP Ethernet might be the best solution but it's not the only or best solution for connectivity directly to the door (Control Panel to reader/lock).

 

i'm getting more confused now

How would you design a door access control system using network protocols?

Will you use both the protocols( Ethernet and TCP/IP) or either of the one or will you use any other option?

Please explain little bit with your ideas so that i can clear my doubt

I apologize in advance for sounding condescending. But I have to the following conclusion…

Perhaps you don’t have the ability at this time to understand the answers to your question. It has been answered many times. But so far, no one has been able to explain it to you in a manner you understand

I’m going to make a VERY loose analogy.

You ask me to drive a car to your aunt at 123 Tacquito Lane, Cancun Mexico to deliver a message.

Driving a car is the hardware layer. Ie, Ethernet.

Her address is like part of TCP/IP. But I need a road map or route. That’s the protocol layer.

But maybe she only speaks Spanish. So I have to as well. Or I only speak English, so she has to also. That’s the application layer. Your question doesn’t even consider that.

Once again, Ethernet or TCP/IP makes no sense. Every part has to match up. If we restrict the discussion to just Ethernet and TCP/IP, then you have to choose an application layer that works with those two.

Several suggestions have been made, but maybe we’ve given you too much information.

Edit: Corrected typo