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dmb2002manFlag for United States of America

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subnet this network with ip address 192.168.147.0

Hey everyone,

I am studying again for my ccna exam and want to recertify so i can start my ccnp eventually but im having a little trouble subnetting even though i understand it pretty good. I know 128, 192, 224, 240, 248, 252, 254. I know 128 has 1 bit turned on and 7 bits turned off, 192 has 2 bits turned on and 6 bits turned off, etc. The on's are 1s and bits turned off are 0s which is host. For example 192.168.1.128 /26, where /26 is 255.255.255.192. well 256-192=64, so 0 64 128, 192, 256, so 128 would fall in between 128 and 192. 192 would be the next subnet. 191 would be broadcast and 190 would be last usable host. Okay so now here is a picture of a full network that i need to subnet using ip address 192.168.147.0. I have to figure out what subnet to use and i am not sure.  I know /27 would give 8 subnets and 30 hosts so im not sure if that would work.  Can someone please explain this better to me.

thanks
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Don Johnston
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How many networks and how many host do you need to accommodate?
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My teacher is very confusing as i went to class tonight and of course he wasnt even there as i am taking the course via online so i get everything through email and dont get no good explaining of it.  I have received this information via email from my ccna instructor but he didnt give us host unless this is it.  

The table below identifies the required placements of the subnets.
 
Subnet Number      Subnet Assignment         
3      LAN on Router0 - Router2 - Router4         
4      Link between Router3 - Router5         
5      Link between Router1 - Router3         
6      Link between Router3 - Router4         
7      LAN on Router1         
8      Link between Router4 - Router5         
9      LAN on Router3         
10      LAN on Router5         
11      Link between Router2 - Router3         
12      Link between Router1 - Router2         
13      LAN on Router0

So i know subnet 3 would be a /27 subnet correct?       
4 would be of course /28?
If he were to give how many host then it would be easy to calculate the subnet address.  Like say if he needed 12 hosts then you do the /28, which would be 255.255.255.240, which is 4 bits on and 4 bits off.  So host would be 2^4-2=14.  That would give us two extra hosts.  I do understand that much but just confused on this network above.
That's one confusing set of requirements.

It looks like there are 11 networks. I don't see anything where the number of hosts are referenced. So if you're not doing VLSM, then you would need a four bit subnet field allowing you to have up to 16 subnets. But that would only leave a four bit host field which would limit you to 14 hosts.

Now if you are doing VLSM (and we still don't know how many hosts are on the five non point-to-point links) then here's how I would approach it.

I would first subnet the address with a /27 mask.

.0  .32  .64  .96  .128  .160  .192  and .224

Take any five of those and use them for the five "LANs" (3, 7, 9,10 and 13)

Take one of the remaining subnets and move the mask right to a /30. Let's say that you selected the .32 for this task. The 30 bit mask would leave a two bit host field which allows you to have only two hosts... Which is all you need on a point-to-point link.

So for the point-to-point links (4, 5, 6, 8, 11 and 12) the subnets would be.

.32  .36  .40  .44  .48  and  .52

Hope this helps.
Hey Don,

thanks for your email back.  Here is a picture actually of the network so you can get a better idea.  It shows the 11 networks in the picture.  This guy is a very confusing teacher as i will make sure not to take anymore classes with him for sure.  I guess i forget to post the picture last night, lol.

Josh
network.jpg
I've been teaching this topic since before ICND (back when the class was called ICRC) and I'm telling you there's simply not enough information to accurately answer the question. I think you're on the right track in making sure you get a different instructor in the future.

If it were me, I'd use a /28 on each subnet.

On the actual exam, you'll be provided with all the information needed to formulate an answer.

I am just so confused on what hes asking and sent him a email last night and no email back from him yet.
Do you even know what this means though.  Does this mean the router 0, router2, router 4 lan lines will be a 255.255.255.224 since subnet number is 3 so that would mean 3 on bits.   So for router 3 and router 5 lan lines then it would be 255.255.255.240 which would be 4 bits on for subnet number.  Subnet 5-13 would be the same way.  Is that what he is trying to ask here.

Subnet Number      Subnet Assignment        
3      LAN on Router0 - Router2 - Router4        
4      Link between Router3 - Router5        
5      Link between Router1 - Router3        
6      Link between Router3 - Router4        
7      LAN on Router1        
8      Link between Router4 - Router5        
9      LAN on Router3        
10      LAN on Router5        
11      Link between Router2 - Router3        
12      Link between Router1 - Router2        
13      LAN on Router0
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Ok so here is what i am going to do then. I will use a \28 subnet mask.  So that would 255.255.255.240
so 256-240=16

0 16 32 48 64 80 96 112 128 144 160 176 192 208 224 240   -- I will then start in the 3rd with .32

3      LAN on Router0 - Router2 - Router4         192.168.147.32
4      Link between Router3 - Router5                192.168.147.48
5      Link between Router1 - Router3                192.168.147.64
6      Link between Router3 - Router4                 192.168.147.80
7      LAN on Router1                                           192.168.147.96
8      Link between Router4 - Router5                  192.168.147.112    
9      LAN on Router3                                            192.168.147.128
10      LAN on Router5                                          192.168.147.144
11      Link between Router2 - Router3                 192.168.147.160
12      Link between Router1 - Router2                  192.168.147.176
13      LAN on Router0                                            192.168.147.192

so for lan on Router 0, Router 2 and Router 3, i could use 192.168.147.33 on Router0, 192.168.147.34 on Router2 and 192.168.147.35 on Router 3.  The available addresses of course would be 192.168.147.33-192.168.147.46, because 47 would be broadcast and 48 would be the next subnet correct.

Routers 3 and 5, i could use 192.168.147.49 on router 3 and 192.168.147.50 on router 5.  The available addresses would be 192.168.147.49-192.168.147.62, because 63 is broadcast and 64 is next subnet correct.

Then for pc0, pc1,  pc2 and pc3, i will assign for the gateway address whatever ip i assign for the port going to the router that its connected too.

For the switches, i wont need to assign an ip address but just connect the correct cable which is a straight through from router to switch.

Let me know if this is good to go this way and then i will be all set with this as its due on monday so i will still have a few days on it.

The rest will be like the above.
Raised the points to 100 for helping me out so much as much as you could.
Looks good to me.

Let me know if it was right.
Hey Don,

Anyway you can let me know your private email since your an instructor and if i have any more questions with this once i get it all setup in packet tracer 5.  I dont have to submit this until monday via email so once i get this setup i just need make sure each and every device can ping each other.

And one more question.  You post this above but shouldnt it be /28 and not /24 since your using 16.  If it were /24, being 255.255.255.0, it would go 256-255=1, so would increment by 1 each time correct.

thanks for all the help as i really appreciate it.

Josh
I offered you the points but please answer my last post.  :)
email address is on my profile.
Hey Don,

I do have one more question. I have setup all the ip addresses in packet tracer and it seems fine. But here is something else that he emailed me too.

-------------------------------------------------------------------------------------------------------------------------

Design the Logical Addressing Space
Given the ip address:  192.168.147.0

Develop an addressing scheme by subnetting the ip address for the packet tracer diagram which is part of this assessment.  Record the resulting addresses in the table below.

Record the subnet mask here:  OK SO I USED SUBNET  /28 255.255.255.240

Subnet #  Subnet Address   First Usable Address   Last Usable Address    Broadcast Address
0                        
1                        
2                        
3                        
4                        
5                        
6                        
7                        
8                        
9                        
10                        
11                        
12                        
13                        
14                        
15                        
16                        
17                        
18                        
19                        
20                        
21                        
22      

How can i fill out the above for the /28 subnet mask.  That seems like /24 above being 0, 1, 2, 3, etc.

What do you think.

Josh                  
I am confused again because /28, will only have 16 subnets and not 22.
Once again, I think we're seeing that your instructor is smoking something.

It could be that he's providing a pre-made form. This would be the same form no matter how many subnets there were.

-dj
Here are the exact instructions in word format.
Instructions.doc
Here's what I think is happening.

This instructor is using some prepared exercises that should be accompanied with additional instructions. But your guy ain't giving the additional instructions. The form would be used for different exercises so there's room for more networks than you're required to define.

This is how I would do it though (just a start).


Instructions2.doc
Hey Don,

I finished everything with my network and i saved it.  Check out each router where you did the ip address and interface and then check out mine because my ip address are different than yours but i think mine is correct.  I also finished subnetting the /28 and check and make sure the last line is correct with the .224 first usable 225 and broadcast 255 and last usable address 254.  I really think im done with this now.

Hey sorry but i had to zip it for some reason it wouldnt take my doc created in office 2007 that i saved in 97-2003 format for some reason.

Once again i appreciate all your help with this.  You should of been my teacher, lol.

Josh
Instructions3a-1-.zip
You left off the last subnet:

192.168.147.240   192.168.147.241   192.168.147.254   192.168.147.255


Ok thanks so does everything else look good in my document.  Did you see where i hightlighted red in there the difference of the ip on the routers that you put in there.  Were you just guessing on that becuase i believe mine is correct but wanted to ask.  I just talked to another guy in my class and he is so lost and asked some of his cisco guys at work and they said theres not enough information, lol.
Looks okay to me.
Hey don,

Its funny i sent my instructor a email last night and still no response back.  Well if i end up failing this course because of this, I am going to contact cisco, because hes making it so unfair.

Josh
Where are you taking this course?
Richland College, in Dallas, texas.   I am enrolled in the cisco academy program.  Its the ccna course but i plan on taking my ccna by december so I am not going to take anymore of the ccna courses but january will enroll in the ccnp courses somewhere but not sure there.  

I have a full lab setup at my apartment now.

2-2620xm routers running advanced ios 12.4 with sdm
1-2610 router running ios 12.3
1-2950 En switch
1-2912 en switch
1-2924 en switch
1-1900 switch
4-2501 routers running 16mb memory, 16mb flash

*looking at purchasing a 12u rack soon.

That may explain it. I've had a number of people come through my public Cisco classes because they were "going to be teaching the Cisco Academy courseware". Most of these people had ZERO actual networking experience.
Right i believe i no more than him to be honest.   I just wish there were better courses in dallas, texas for training that are not bootcamps.  I was trying to gather a team of people around here to cram and get ccna by december and then start ccnp january and i will have a complete network for us to train on but no one really seems interested so i will just study and do it on my own.  I think half the class already dropped the course because they were so lost and really the exploration videos dont explain it all that good.  I have been reading the Cisco CCNA Study Guide Exam 640-802 6th Edition which pretty much covers it all and easy to read with lots of examples.  Its a 1000 page book and im on page 600.  I also read a 90 page book just on subnetting.  I will bet alot of people will not complete this assignment.  I might be the only ONE. LOL
Its funny i didnt even watch any of the academy vidoes after chapter 1 and just went and took all the test and have over a 90% because the questions are pretty well straightforward.
Hey Don,

In packet tracer i setup my network and i just setup a routing protocol.  I just configured this on all the routers.  

router rip
version 2
network 192.168.147.0

But now when i go to a switch and try to ping one of the pcs it wont let me.  Do i need to configure a default gateway on the switches in order to do this.  If so i just use the gateway for the switch that the router is connected to right for that port.

thanks,

Josh
Yes. In order to communicate with a device on the different network, the switch will need a default gateway.
Hey do you have packet tracer 5.0.  I could upload this file and have you check it reallly fast.  I configured a default gateway on one of the switches but it wont even ping the gateway so something is wrong with that.

Josh
Fire away.
Here you go.  So i just received a email from the instructor saying he wants me to come by tonight and talk to him because i told him his directions for this are terrible. Its weird in packet tracer i only show 62% complete and i dont even know what else i can do with this.  Hopefully you can help me out with this.

I had to name the name the file .doc so when you get it just rename it to .pka and it should work.

thanks so much, you should of been my teacher!!!!!
JoshB.doc
It's showing "not a valid packet tracer file".

I've go version 4.1 so I don't know if that's the problem.


no i had to rename it because it wont let me upload that file with extension pka even if i zip it up.   I think thats the problem because i am renaming it and then its corrupting it.  Send me a email to my private email at josh.brewster@gmail.com and i will forward this packet tracer file to you.

Josh