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What is the difference between network devices and network interfaces?
“Device” is an overloaded word. It’s sometimes used to mean a machine, and sometimes to mean a peripheral or interface of a machine. Each network interface has its own address. Each machine has zero, one or more addresses depending on how many network interfaces it has.
Is an IP address specific to a device or network?
An IP address is a unique address that identifies a device on the internet or a local network. IP stands for “Internet Protocol,” which is the set of rules governing the format of data sent via the internet or local network.
What is a network interface IP address?
The IP address of network interface is in most cases a dynamic, private IP address which was given to the network interface by the DHCP (server or router). If device A and device B are on the same network, and the MAC address of device B is known by device A – they can communicate directly based on the MAC address.
How many digits is an IP address?
So now that you understand a bit about binary (pun intended), you can understand the technical definition of an IP address. To your computer, an IP address is a 32-bit number subdivided into four bytes.
Why are IP addresses given to each interface and not device?
If they’re in the same network, they send directly; otherwise, they send to a router whose job is to get the message closer to the destination. So if a device is connected to multiple networks, it needs an address on each of those networks so it can be reached by devices on that network.
How many network interfaces does a device have?
Your device may have several network interfaces. Those can correspond to real devices ( NICs) or be virtual. In order to be usable (i.e. initiate or listen for connections), each interface should have an IP address. Usually there will be one IP per interface, but it’s possible to have several via IP aliasing.
How to assign an IP address to a device?
But you can use “IP unnumbered”, and not associate any IP addresses to those links. Now, you assign an IP to the device’s loopback interface (any interface really, but loopback is the easiest one for this purpose), and you use a dynamic routing protocol (IS-IS, OSPF, EIGRP…).
When do I use an IP address for a machine?
When you access a machine over the network, you use an IP address, so you’re in fact accessing a specific network interface of that machine. In most cases, the distinction is moot, because only one interface is reachable from the remote machine, and it wouldn’t make any difference anyway, because programs accept connections on all interfaces.