Whats The Difference Between A Port And An Interface?

adassus

Hello all,

I'm currently going through my CCNA prep and I'm kinda confused between the terminology. Whats the difference between a port and an interface on a switch?

tech-airman

adassus wrote:

Hello all,

I'm currently going through my CCNA prep and I'm kinda confused between the terminology. Whats the difference between a port and an interface on a switch?

adassus,

To me, the difference between a port and an interface is hardware and software. The port is where you plug in the physical cable connector. The interface is what you configure in the Cisco IOS, therefore is the software representation of the physical port.

I hope this helps.

scheistermeister

Nevermind, I should have read the whole thing.

kenny504

In all my career i have heard the two terms used interchangeably. You have logical ports like loopback ports configured on your router but they are also virtual or logical interfaces. The real question is if the port or interface is a physical one or logical. Your telnet vitual terminal lines are actually logical ports for telnet clients to connect on. Physically you cannot see those ports, just like your loopback but they are there and functioning.

In short

Logical Port = Logical Interface
Physical Port = Physical Interface

Be careful of the word "port" used in different context. Some may be referring to TCP or UDP ports instead of physical layer ports. This is the only rational difference i see between port and interface. The TCP port, this specifies a virtual port at layer 4 or the OSI.

lol...but hey I know some instructors that refer to TCP or UDP ports as "virtual service interfaces" like DNS uses port 53 which is its virtual service interface.

Hope this helps...

Kenny

scheistermeister

kenny504 wrote:

Logical Port = Logical Interface
Physical Port = Physical Interface

That is basically what I said before I edited my post. Reason why I edited it was that I later read the part that says "on a switch". When configuring a which you can have all kinds of logical interfaces like interface vlan 1 or an etherchannel interface that is not a physical interface. When you say something like port 1 or port 24 people are generally referring to the physical port.

miller811

It could also mean
console port
network interface