Penetration Testing

To help with this testing, I am currently downloading Kali Linux, a Linux designed for penetration testing.

Presentation Practice 2

For the second presentation I recreated my slides from the first one, making sure to include more details on where I'm up to. I thought it went alright, I just need to practice the finer details a little more.

Using DHCP Server in Simple Network #1

To test my DHCP server, I have created a basic network with 2 switches, an access point, and the server.

I've used Packet Tracer to show what the network I've created looks like.

The server is currently connected to S1 via a layer 3 connection, the rest is layer 2.

After setting up all the parts, I have been able to connection to the wireless connections but been unable to gain an address via DHCP. I started debugging and received the following prompt on S1, the layer 3 switch.

Server Creation Part 2

The operating system which I have chosen to run my DHCP service along with others is Ubuntu. 

The latest version of Ubuntu Server is currently 14.04. I would be using this, however my spare PC is x86 and this version of Ubuntu (Server) only supports a 64 bit processor. Therefore I have stepped back one edition to 13.04.

Like Windows, I attempted to install Ubuntu using a USB drive. However, a bug with these versions of Ubuntu throw up errors in the installation requesting the image to be inserted via a CD. The only way around this I found unnecessary, so I flashed the image to a CD and installed it that way.

Server Creation Part 1

For the next step in my network, I require the use of a physical DHCP server.

As a back-up to creating my Ubunutu Server, I have a second hard-drive which I will use for Windows Server 2008.

First, I did some testing creating a virtual machine running the O/S I plan on using. This is shows the DHCP service installed and running.

To install Windows on to my machine, I utilized an ISO image and flashed it to a USB drive to install using Microsoft software.

As shown above, there's my working Windows Server with my spare machine.

Solving Cisco Configuration Professional (CCP) not loading Correctly on Internet Explorer

On the school machines, CCP was not able to load correctly with the default Internet Explorer. 

To over come this, I closed CCP and opened Internet Explorer separately.

I then hit 'alt', when up to the 'tools' option and selected 'Compatibility View settings'.

I then added the local host address of '127.0.0.1'.

I then restarted CCP successfully.

Current Progress

Using virtual machines, I have been experimenting with two alternatives to Ubuntu, Windows server 2003 & Windows Server 2008. 
What I have discovered is that they're much easier to use (initially) when starting to set up, as they can be created with a full desktop experience. That means that I would not need to necessarily rely on CLI. However, I am still choosing to pursue Ubuntu server as it's open-sourced at no cost and is widely supported online. I may use the 'simple' windows servers initially before I have Linux running fully to test DHCP etc.

Fortunately for Ubuntu, I have found to very helpful pages that shows the setup of many primary resources that I will need to:
Ubuntu 14.04
https://help.ubuntu.com/14.04/index.html
Ubuntu 12.04
https://help.ubuntu.com/12.04/index.html

I have also been researching programs that may be useful to for video streaming, Plex Media Server and VLC media player. Both are supported on Ubunutu & Windows. 

For the beginning of my stress testing, I have been looking at DDOS attacks. These I could put through the network using a program called "High Orbit Ion Cannon", a piece of software that generates fake users & connections to the server attempting to overload it.

Real-World Network Address Testing

As Nathan and I discussed, giving both our buildings the same address range would create a dis-contiguous network, resulting in lost packets and a confused routing protocol. Because of this, we decided the two separate buildings would have separate networks that both grant the same privileges. The only way to overcome this without having two separate networks would be to use a tunnel, which creates unnecessary stress and overhead to our network.

To check this idea, I went to three separate areas of the MIT wireless network to capture the address information from each block. First the Library, secondly P Block, and lastly JKL Block. 

As these three screenshots show, although the network is always "MIT-Wireless", the ip address is actually in different subnets. Most the addresses remain the same, which makes sense, but each separate building is treated as a different network.

DHCP with layer 3

Thanks to the help of Nathan, we were able to solve the issue resolving in DHCP requests/addresses being returned to users through a layer 3 network. 

Once turning on debugging on the DHCP server, in our testing case we were using a router for simplicity, it was apparent that the server was receiving the requests from hosts. However, once the request is sent, the reply is not received. It turned out that the problem lied with the routing protocol, not DHCP itself. To solve the issue a redistribute subnets command was applied to the edge layer 3 routers. 

So that the users are given the correct address/network, an SVI with a corresponding network address in a vlan is used. So that when the broadcast is sent, it shows as that network, therefore receiving an address from the correct network. There is also a ip-helper command applied to each Vlan.