Hallo wissende Gemeinde,
ich möchte für meine Diplomarbeit Probemessungen von Dämpfungswerten für verschiedene Gebäudestrukturen (Wände, Türen, Fenster usw) durchführen.
Nun bin ich auf das kostenlose Tool NetStumbler (http://www.netstumbler.com
) gestoßen. Ich muss zugeben das meine physikalischen Grundlagen nicht die besten sind und weiß nicht wie ich aus den dort gegebenen Werten die Dämpfung berechnen kann. Ich hoffe einige hier können mir helfen bzw. ein anderes kostenloses Tool empfehlen.
Angefügt ist ein Screenshot der Werte für meinen Router daheim.
Und hier eine kurze Erklärung der Werte:
MAC - Media Address Controller Address - This is basically the hardcoded address of the Access Point. This is coded at the factory by the vendor and is usually unique for each AP (unless the address is spoofed)
SSID - Service Set Identifier - The name of the network that the clients use to identify which network they are communicating with. Some APs send out their SSID in Beacon Packets in order to let clients know how to communicate with them. A common security method for securing APs is to turn of the transmit of Beacon Packets.
Name - Not sure myself yet
Channel - The channel that the AP operates at. THere are 12 channels in the US and 14 international.
Vendor - The company that sells the AP.
Type - The type of device that NetStumbler detected. The two types that I have encountered so far are AP (Access Point - AP acts as a server and clients communicate with it directly) and PEER (Peer to Peer Network (ad-Hoc) - clients communicate among themselves. Usually somewhere on the network is a gateway to an in internal network). If anyone knows of any other types please post them.
Encryption - The type of encryption used on the network. So far I have only seen WEP (Wireless Encryption Protocol) which can only encrypt data packets while the other packets such as beaconing, probes, and joining are left unencrypted. This supposedly means that you can see packets that relate to the AP brodcasting its SSID and clients probing and joining the network, but all of the actual data packets (could be anything ie: HTTP, AIM, FTP) are encrypted. There are methods in which to brute force the WEP key as well as cracking the key through weak keys.
SNR - Signal to Noise Ratio - Higher is better and any positive number is decent.
Signal+ - The best Signal that NetStumbler has picked up on the current scan (higher is better).
Noise- - The least amount of Noise that NetStumbler has picked up on the current scan (lower is better).
SNR+ - The best Signal to Noise ratio that NetStumbler has picked up on the current scan (higher is better).
Latitude - Im assuming your current latitude based on a GPS device.
Longitude - Im assuming your current longitude based on a GPS device.
First Session - The time that you first recieved packets from the current AP.
Last Session - The last encounter that you had with the AP.
Signal - The current signal that you are recieving from the device. Higher is better. The strength on the signal can be influenced from a number of factors including strength of the cards probes, strength of the device, obstructions that might be in the way of your communication path, etc.
Noise - The current amount of noise that is being picked up by your card. Lower is better. Noise includes signals being picked up by devices other than APs that operate at the same frequency as 802.11b (2.4ghZ). These include cordless phones and other Wi-Fi devices.
Flags - (from official FAQ) The flag field contains the 802.11 capability information in hexadecimal. It's documented in section 188.8.131.52 of the 802.11b spec. To save you having to go and look, the bits are:
0001 ESS ("Infrastructure")
0002 IBSS ("Ad-Hoc")
0008 CF-Poll Request
0010 Privacy ("WEP")
0020 Short Preamble
0080 Channel Agility
Beacon Interval - I am assuming that this is the interval in milliseconds at which the device is sending beacon packets.
Any information that can be added to this is greatly appreciated