code:

Given the following IP address and mask, provide the class, 
network ID, # subnets, and # of hosts per net:


Address/mask        Class  Net ID              #subs    # hosts
==================  =====  ==================  =======  ========
___.___.___.___/__    _    ___.___.___.___/__  _______  ________

172.35.67.123/18
4.2.2.1/29
201.31.122.43/27
125.163.227.5/30

I'm working up a batch of "new" questions that will emphasize
summarization techniques. Be afraid! (Just kidding!)



Here's the answer to yesterday's question:

code:

You're "the" network admin for a mid-size company, and you 
had the intelligence to insist on a two-layer firewall to 
create a true DMZ when you're boss wanted to connect to 
the Internet for his email.  Your boss has just gotten 
back from a security conference, where he heard the phrase 
"B2B DMZ."  Now he wants one, too.

Your ISP assigned 1.2.3.128 /25 for your company.  You 
currently have 8 devices, including the Internet router, 
mail server, DNS, e-commerce webserver, and inside firewall 
using .129 through .136.  You need to further subnet the 
provided addressing to support the following requirements:

- As your company grows, you expect that 10-12 additional 
  servers may be required in the main DMZ in the next 
  few years.

- The B2B DMZ needs to support 2 VPN routers, the Internet 
  router, and two future VPN routers

- The ability to add three more "4-device" DMZs for other 
  connectivity.

- Identify the unallocated IP address ranges.


Answer:          1.2.3.
         Main DMZ     .128 /27 - provides 30 hosts from .129-.159
  	B2B DMZ      .160 /29 - provides 6 hosts from .161-166
	Future DMZ 1 .168 /29 - provides 6 hosts from .169-174
 	Future DMZ 2 .176 /29 - provides 6 hosts from .177-182
 	Future DMZ 3 .184 /29 - provides 6 hosts from .185-190
 	Available    .192 /26 - address .193 through .254 available