In an ethernet network there are 4 devices that from the the outside look very similar. In this article we will look at the difference between hubs, switches, bridges, and routers.
Hub
A hub is the simplest of these devices. Any data packet coming from one port is sent to all other ports. It is then up to the receiving computer to decide if the packet is for it. Imagine packets going through a hub as messages going into a mailing list. The mail is sent out to everyone and it is up to the receiving party to decide if it is of interest.
The biggest problem with hubs is their simplicity. Since every packet is sent out to every computer on the network, there is a lot of wasted transmission. This means that the network can easily become bogged down.
Hubs are typically used on small networks where the amount of data going across the network is never very high.
Bridge
A bridge goes one step up on a hub in that it looks at the destination of the packet before sending. If the destination address is not on the other side of the bridge it will not transmit the data.
A bridge only has one incoming and one outgoing port.
To build on the email analogy above, the bridge is allowed to decide if the message should continue on. It reads the address bob@smith.com and decides if there is a bob@smith.com on the other side. If there isn’t, the message will not be transmitted.
Bridges are typically used to separate parts of a network that do not need to communicate regularly, but still need to be connected.
Switch
A switch steps up on a bridge in that it has multiple ports. When a packet comes through a switch it is read to determine which computer to send the data to.
This leads to increased efficiency in that packets are not going to computers that do not require them.
Now the email analogy has multiple people able to send email to multiple users. The switch can decide where to send the mail based on the address.
Most large networks use switches rather than hubs to connect computers within the same subnet.
Router
A router is similar in a switch in that it forwards packets based on address. But, instead of the MAC address that a switch uses, a router can use the IP address. This allows the network to go across different protocols.
The most common home use for routers is to share a broadband internet connection. The router has a public IP address and that address is shared with the network. When data comes through the router it is forwarded to the correct computer.
This comparison to email gets a little off base. This would be similar to the router being able to receive a packet as email and sending it to the user as a fax.
can you please give all this comparioson between network control devices in chart form? which will be helpful to understand it easily and comparitively.
thx dude!
can u tell me that what is subnetting and subnet masks ?
@Ammar – That’s something that could be several pages of explanation and not something that would neatly fit in a blog comment.
nice.. these simple explanations wud b helpful for the begineers :)
This is really helpful for the beginner, but there functions are different so if you explain in figure or structure with the expanation it will be more helfful. Thanx
Hi dude,
Thanks for the info its very useful.
Short, clearly, easy to understand.
Thanks for this overlook! It helped me very much to get access to my learning stuff for the university. This introduction was exactly what I was looking for after having taken the first look inside my study documents.
Thanks a lot! Greetings from Germany!
hey this is highly helpful. Thanks a lot…
Thank you so much for breaking all of this down! I really needed this for a course paper.
tanx for valuable information
thanx 4 urs valuble info….it helps me a lot…thanx …
its really useful for me to understand the difference between these LAN devices. thanx :D
thanks buddy..
it helped me alot
thanks buddy it will help in my seminar presentation…….. cheers
thanhs a lot for helping me
thx man really helped out. this info is brief and to the point. its greta for beginners
Very nice article. Exactly what I was looking for.
Thx dude ;)
thnxx
thnx a lot Ryan….your way of description is nice and is a good starting point for this topic…..it helped a lot :)
hey it was quite helpful, thnx bro……………
it is cool for beginners
n it is better to explain it diagramatically.
tnx anyways
It’s really good…. i appreciate this….
thanks for this simple explanation…
It is very simple and useful description ,thanks
Good document. Brief, clear and easily understandable.
really good and helpful for a begineer
Not to be a jerk (and perhaps I’m even wrong), but when you talk about a switch forwarding a packet shouldn’t it really be a frame?
There’s probably quite a bit technically wrong in this description :)
It’s really helpful for the beginners; but it is one step up to the good understanding of the device functions.
Nice tutorial man. It makes very easy to understand different network devices with very little effort. Carry on.
good article……but I donot understand exactly the difference b/w bridge and switch……if both checks for destination address and then only forward the data………
A bridge typically changes from one type of connection to another. For example, my computer is plugged in to an Apple Airport Express that acts as a bridge to the rest of my wireless network. So it bridges between a wired cat5 connection and a wireless connection.
A switch typically is multiples of the same type of connection. So you might have a switch with 5 ethernet connections that can all talk, but the switch acts as traffic control between them.
Thank you for simple yet very clear explanation of these things.
simple and clear explanation
excellent review……..1
thanks….
thankx…
it is realy simplest documents….thankx a lot…..
Simple and concise. Thanks!
it is a good and simple language. thanks
the concept that is imparted briefly sounds better for those who are just making inception towards computer and communication
thx alot
this make me understand the correct difference between router,bridge,switch and hub……….
without reading this i m not able to understand..
it helps a lot and make me tens. free
yyuuuuuuuuupppppppppiiiiiiiiii
thnx
can router use as a switch?
Easy and really explicit breakdown of knowledge,nice.More.
Explained in easily understandable English
Can we manage a bridge? can we make VLANs in a bridge?
Thanx for information
Bridges are software based, whereas switches are hardware based. Bridges too can have mutiple ports. Am I wrong?
Windows lets you create a software bridge if you have a computer with 2 or more network connections. I did this for a while with my media center computer to bridge its wired and wireless connections so that a couple other devices could also connect via wireless. A little hinky, but it did what it needed to do.
But bridges can be hardware too. I’m using an Apple Airport Express under my desk to connect two sections of wired networks together. DHCP server is on one side and both sides have a switch connecting multiple ethernet devices together. One switch connects to the Airport Express which gives that entire side access to the wireless connection.
Thanks Ryan!!!
Thank you for taking the time to explain all this stuff. Would you mind drawing this out visually? It doesn’t have to be pretty… hand drawn on a piece of paper and scanned or just draw boxes / lines in like Paint or whatever would be so helpful. I’m really having a hard time visualizing your setup to see the benefits of a bridge over a switch.
This is really helpful and very simple language and understandable doc. I just tell you I become always confused about all devices. Now I can distinguish them all.
Hello,
Could you please give me an example for the communication between Hub to Bridge ,Brdige to switch and Switch to Router …please let us know where ARP and NAT is used in these devices
thanks !!!
I just like the helpful information you provide to your articles. I will bookmark your weblog and check again here regularly. I’m rather sure I will be told lots of new stuff right here! Good luck for the next!