Which subnet masks are valid for a subnetted Class B address?

Posted by Daddy Warbox on Super User See other posts from Super User or by Daddy Warbox
Published on 2010-03-24T15:04:02Z Indexed on 2010/03/24 15:13 UTC
Read the original article Hit count: 363

Filed under:

subnet

|

ip-address

|

networking

|

homework

Yes, this is a school question, and yes I already know the correct possible answers (supposedly), so I'm not going to bother posting them. Instead, I just want to understand the meaning of this question. I know what class B addresses are, and what valid class B subnet addresses are. I guess one way to define my question is to ask why the answer "255.255.0.0" is wrong, necessarily? That seems to defy my understanding, or else some part of my brain is just not registering the question correctly.

Thanks in advance.

© Super User or respective owner

Related posts about subnet

Can I subnet a subnet?

as seen on Server Fault - Search for 'Server Fault'
Apologies in advance for the botched terminology. I have read the Server Fault Subnet Wiki but this is more of an ISP question. I currently have a /27 block of public IPs. I use give my router the first address in this pool and then use 1-to-1 NAT for all the servers behind the firewall, so that… >>> More
Connecting to a remote server through OpenVPN when local network subnet conflicts with remote network's subnet

as seen on Server Fault - Search for 'Server Fault'
After connecting to a remote location via OpenVPN, I am trying to access a server on a network that exists on a subnet such as 10.0.1.0/24. However, the network I am trying to access this remote server from is on the same subnet: 10.0.1.0/24. I am unable to connect to my remote server via typing… >>> More
How to Route Traffic in Case PPTP Remote Client is on Same Subnet as Server

as seen on Server Fault - Search for 'Server Fault'
I've a PPTP server setup on my local home network (192.168.1.0/24, pfSense). Now sometimes when I'm away and want to connect remotely my client (Windows 7) is also on the same network because e.g. the hotel has set it up the same way. Thus the connection works, but I can't reach any PC on my home… >>> More
Changing subnet-mask of class-c network host to 255.255.0.0

as seen on Server Fault - Search for 'Server Fault'
We have a existing class-c network with IP address range 11.22.33.44/24 (just for example). My domain controller has been configured within this subnet. So all servers within this subnet have subnet mask configured to 255.255.255.0. Now we have got a new subnet with IP address 11.22.88.99/24 (note… >>> More
Issues resolving DNS entries for multi-homed servers

as seen on Server Fault - Search for 'Server Fault'
This is difficult to explain, so bear with me. We have 2 domain controllers, each multi-homed to straddle 2 internal subnets, (subnet A and subnet B) and provide dns, dhcp, and ldap authentication. Both domain controllers each have 2 DNS entries. both entries have identical host names, but correspond… >>> More

Related posts about ip-address

Logging IP address for uniqueness without storing the IP address itself for privacy

as seen on Stack Overflow - Search for 'Stack Overflow'
In a web application when logging some data I'd like to make sure I can identify data that came at differetn times but from the same IP address. On the other hand for privacy concerns as the data will be released publicly I'd like to make sure the actual IP cannot be retrieved. So I need some one… >>> More
Problem with setup VPN in Ubuntu Server 12.04

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I have a problem with setup VPN server on my Ubuntu VPS, here is my server environments: Ubuntu Server 12.04 x86_64 xl2tpd 1.3.1+dfsg-1 pppd 2.4.5-5ubuntu1 openswan 1:2.6.38-1~precise1 After install software and configuration: ipsec verify Checking your system to see if IPsec got installed and… >>> More
Problem with setup VPN on Ubuntu Server 12.04

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I have a problem with setup VPN server on my Ubuntu VPS, here is my server environments: Ubuntu Server 12.04 x86_64 xl2tpd 1.3.1+dfsg-1 pppd 2.4.5-5ubuntu1 openswan 1:2.6.38-1~precise1 After install software and configuration: ipsec verify Checking your system to see if IPsec got installed and… >>> More
My Ip Address - Windows Vista - ipconfig : Cant find my ip address

as seen on Super User - Search for 'Super User'
Hi, I type in doc $ ipconfig but not get My Ip Address. I get other values but not my ip address. Please help me, Thanks Yosef My Computer: Windows Vista adsl router (for few computers) My Ip is temp each time that i connect web he change >>> More
Determine if IP Address is Cellular IP Address

as seen on Stack Overflow - Search for 'Stack Overflow'
In .NET Compact Framework a device can have several IP Addresses I want to find one that is NOT coming from the Cellular connection. Goal is for WiFi or Ethernet connection. Is there a way to do this? Seems like State and Notification Broker would have a way to do this but didn't see a way. >>> More