Solved

Subnetting Help

Posted on 2013-11-13
4
436 Views
Last Modified: 2013-11-13
HELP!!!

I have been given an assignment to perform subnetting and although I know the very basics, this has me working like a monkey doing a math problem.  I am beyond lost.

The assignment states:

Develop an IPv4 addressing scheme for a remote office using the address 172.36.0.0/23 with a minimum of IP waste for PC networks and exactly the correct number of IP's required between routers.  Also to provide a list of available (unused) nets by using the least number of bits for the subnetmask - CIDR.

Router One:
     Finance = 11PCs
     Account Room = 228 PCs
Router Two:
      IT Office = 5 PCs
     Web Sales = 58 PCs
Router Three:
     Administration = 5 PCs
     Business Section = 112 PCs

I have to provide the following for each (finance, IT Office,Administration, Business Section, Account Room, Web Sales) :
     Subnetmask being used
     NET ID
     IPs required
     IPs calculated
     First available host address
     Last available host address

Connections between the firewall router and router :
    subnetmask used?
     NET ID used?
     IP address assigned to firewall connection?
     IP address assigned to router 1 on firewall side?

Connections between router 1 & router 2
     subnetmask?
     NET ID?
     IP of router 1?
     IP of router 2?

Connections between router 2 & router 3:
     subnetmask?
     NET ID?
     IP of router 2?
     IP of router 3?
0
Comment
Question by:tmartin40
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
  • 2
4 Comments
 
LVL 12

Accepted Solution

by:
Henk van Achterberg earned 500 total points
ID: 39646087
Ok, the smallest subnet between routers is 255.255.255.252 (four IP's, first IP is NETWORK address, last IP is broadcast address).

so we start with the firewall and routers:

172.36.0.0/30 <- NETID
172.36.0.1 - firewall
172.36.0.2 - router 1

172.36.0.4/30 <- NETID
172.36.0.6 - router 1
172.36.0.7 - router 2

172.36.0.8/30 <- NETID
172.36.0.9 - router 2
172.36.0.10 - router 3

Then you need the subnets for the routers:

Router One:
     Finance = 11PCs 172.36.0.32/28
     Account Room = 228 PCs 172.36.1.0/24
Router Two:
      IT Office = 5 PCs 172.36.0.16/29
     Web Sales = 58 PCs 172.36.0.64/26
Router Three:
     Administration = 5 PCs 172.36.0.24/29
     Business Section = 112 PCs 172.36.0.128/25

so that have we used:

172.36.0.0/30
172.36.0.4/30
172.36.0.8/30
172.36.0.12/30 [UNUSED]
172.36.0.16/29
172.36.0.24/29
172.36.0.32/28
172.36.0.48/28 [UNUSED]
172.36.0.64/26
172.36.0.128/25
172.36.1.0/24

Here ya go
0
 

Author Comment

by:tmartin40
ID: 39646123
OK, let me show my ignorance...

The subnetmask for the firewall and all routers is 255.255.255.252 and 172.36.0.0/30 is the netID for the firewall/router 1.  The "/30" is confusing to me.  This confusion carries over to the departements.  For example:

Finance = 172.36.0.32/28... This translates to a host IP range of 172.36.0.33-172.36.0.46 with a net id of 172.36.0.32, a broadcast ID of 172.36.0.47, and a subnet mask of 255.255.255.240?
0
 
LVL 12

Expert Comment

by:Henk van Achterberg
ID: 39646143
0
 

Author Comment

by:tmartin40
ID: 39646146
Got it, THANKS!!!  You are a life saver!
0

Featured Post

Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Data center, now-a-days, is referred as the home of all the advanced technologies. In-fact, most of the businesses are now establishing their entire organizational structure around the IT capabilities.
Microservice architecture adoption brings many advantages, but can add intricacy. Selecting the right orchestration tool is most important for business specific needs.
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…

730 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question