Subnet/Switch Clarification

up2thetime

Hey I was wondering if someone could please clear something up.
I was having a debate at school with a friend of mine about subnetting and broadcasts.

Firstly, if we have an address of 192.168.1.0 and Subnet Mask of 255.255.255.252, it is my understanding that:

192.168.1.0 is the Network ID
192.168.1.1 is a valid Host Address
192.168.1.2 is a valid Host Address
192.168.1.3 is the Broadcast address and cannot be assigned to a host.

According to my friend, 192.168.1.3 is a valid host address.

Is he correct?

Secondly, it is my understanding that a switch (assume it’s a Layer 2 switch with no VLANs configured) breaks up collisions domains. However all hosts connected to that switch are on the same Broadcast domain and will therefore receive broadcast messages. According to my friend, switches will not propagate a broadcast.

Is he correct?

Thank you.

mikej412

up2thetime wrote: »

Is he correct?

No and No.

Maybe it time to find a smarter friend

dynamik

It sounds like your friend has a case of the dumb

Have him try to configure a NIC with those settings in Windows if he doesn't believe you (it will yell at him).

Edit: It's like Mike and I, one of us is a little slow...

mikej412

up2thetime wrote: »

I was having a debate at school with a friend of mine

Careful..... he may have just been testing you to see if it's worth copying off your paper during exams.

Bert McGert

Sir, according to my calculations, your friend is absolutely correct.

Stick with him, he knows what he's talking about.

Slowhand

Bert McGert wrote: »

Sir, according to my calculations, your friend is absolutely correct.

Stick with him, he knows what he's talking about.

And if you believe that, I've got a big, red bridge in San Francisco to sell you.

up2thetime wrote: »

Secondly, it is my understanding that a switch (assume it’s a Layer 2 switch with no VLANs configured) breaks up collisions domains. However all hosts connected to that switch are on the same Broadcast domain and will therefore receive broadcast messages. According to my friend, switches will not propagate a broadcast.

Is he correct?

Thank you.

Your thinking on this is correct, a layer 2 switch will only break up collision domains and leave broadcasts alone to go merrily along, by default. As for layer 3 switches, you'll have to pick Mike's brain, my experience with them isn't such as to answer with 100% certainty.

blackninja

Bert McGert wrote: »

Sir, according to my calculations, your friend is absolutely correct.

Stick with him, he knows what he's talking about.

I'll not be using any sarcasm today

Subnets are:

192.168.1.0
192.168.1.4
192.168.1.8

192.168.1.3 is the Broadcast address and cannot be assigned to a host.

So how can 192.168.1.3 be a valid host?





Have you been drinking?

mikej412

Bert McGert wrote: »

Stick with him, he knows what he's talking about.

Are you "the friend?"

Ooooh..... to the original poster: are you both applying for the same Internship position somewhere? That could explain "your friend" and his "answers."

up2thetime

mikej412 wrote: »

Are you "the friend?"

Ooooh..... to the original poster: are you both applying for the same Internship position somewhere? That could explain "your friend" and his "answers."

LOL!!

No no, we were just in class and got on the topic of subnetting, which turned into a long argument about broadcast addresses and switches.

I was pretty sure that I was correct. Just wanted to confirm with the experts

ColbyG

Your friend needs help.