All posts by Stan

Windows NMAP “refresh_hostbatch: Failed to determine dst MAC address for target” error

Tips

The “refresh_hostbatch: Failed to determine dst MAC address for target” is a long standing error in NMAP for Windows, and will still be there for a while.

The error appears usually if you are trying to scan an ip address from the same network with the MAIN IP on your scan machine. Try to scan a www.anywebsite.net address. If you get no error, read on.

There are a few fixes available:
1)      If you do not have access to “Network settings” on your Windows machine, you may add the “–unprivileged” parameter to your NMAP command line. This will not work for the raw modes, but it will give you at least quick access to basic scan.

2)      You may add another IP Address to your local machine, as FIRST IP. On Windows XP go to Start->Control Panel->Network connections->Right click on “Local area connection(or whatever name you may have for)”->Properties->Internet Protocol(TCP/IP)->Properties->Advanced. Here, add an IP address form another bogus network you are not using on your Lan (like 10.125.120.100/255.255.255.0). You may need to delete the main IP and add it after the bogus one. The trick is that, if you type ipconfig in your console, you should see the bogus IP first, the main IP address second.

It looks like NMAP is confused by some things in Windows, and one of those things are the IP addresses in the same broadcast domain.

Enjoy the dirty trick, and, if NMAP developers are reading this, they will definitely know what to do in order to fix it 😉

Howto download pdf ebooks from Scribd for free

Tips

Howto download pdf ebooks from Scribd for free (and plant a tree)

If you do not want Scribd to mess around your facebook personal data, here is your clean (nothing to install) trick:

Start your Firefox browser and open about:config in a new tab. Accept the warning.

Select and copy “general.useragent.override” without quotes.
Right click on the page, click New, click String.
Right click and Paste for new string value.
Hit enter for value.

Select and copy “Opera/9.80 (J2ME/MIDP; Opera Mini/6.24288/25.729; U; en) Presto/2.5.25 Version/10.54” without quotes.
Go back to the about:config tab, hit Enter. Right click and paste for the value.

Great, now hit reload on the Scribd page. The website think you are on a mobile phone and will offer you a BIG download button. Use it wisely 🙂

Now, since your browsing experience will be somehow weird (all the websites will think you are on a mobile device), go back to the about:config tab.
Right click on the blue line (general.useragent.override) and hit reset.
You may close the about:config tab now.

The browser is back to his initial state, no plugins installed, no backdoors, no ads.
Clean like a child 🙂

Enjoy your book, be smarter, and share the knowledge.
If you love the book, buy it.
Buy the book in electronic format, it is cheaper and you save a few branches from a tree.

For every 10 books downloaded using this trick, consider planting a tree.
Is simple and gives you inexplicably satisfaction.
You will be amazed how fast those trees grow. And they need nearly nothing. Not even close what a dog needs to grow.
And dogs do not create Oxygen, you know?

Brickcom WVB-650N 5Ghz WIFI Bridge

WIFI

Feature short list:

Unfortunately only one Ethernet port.
Unfortunately the Ethernet port is 100Mbps.

It looks like is using at least two streams of 54Mbps. With one TCP connection, rates are around 50Mbps. With two ore more TCP connections, rates are going up to 95Mbps.
It should be hacked and, if there are more than two streams, Ethernet chip must be upgraded to Gbit.
The manual channel setting is sometimes faulty.
Inside the box, there are 4 antennas. There are 3 more places for 3 Ethernet ports, the Ethernet connectors, transformers, few SMD condenser and resistors missing.

The good things: the connection IS stable (as in like wire stable).
The device goes through 3 walls. In the same scenario, any tested 2.4 router (on an unshared radio channel) was not able to offer the same performance.
The ping times are consistent (exactly 5ms).
The devices are hardware identical, so, they can be configured as AP or SA, as needed.
Tested as AP paired with a CISCO AE2500 USB WIFI stick showed the same 95Mbps sustained rates (through one brick wall plus other wood/metal obstacles).
I’ve been using the bridge for 6+ months for my home Internet connection, to check reliability. No reset needed, no “blackout” type problem always meeting with 2.4Ghz equipment.

Conclusion: this is the first WIFI device behaving reliable I have ever seen. Preview dual band WIFI routers (Linksys and other) are way lower on reliability and ability to go through walls.

IPCam Brickcom WCB-100Ae

IP Camera

Specificatii:

+ 15 fps
+ rezolutie 1280 x 800
+ codecuri H.264, MJPEG, MPEG4
+ conexiune ethernet si WIFI
+ optiune https
+ microfon

Observatii:

Conectata pe ethernet si monitorizata pe ethernet cu notebook, pe http, am masurat urmatoarele rate de transfer (DU Meter, scena statica/scena miscata):
 + H.264, 1280 x 800, 15fps, Best quality(6): 10.6 mbps/11.8 mbps (dinamica scenei nu pare sa influenteze rata de transfer);
 + H.264, 1280 x 800, 15fps, Acceptable quality(1): 490 kbps/560 kbps;
 + MJPEG, 1280 x 800, 15fps, Best quality(6): 7.5 mbps/8.7 mbps;
 + MJPEG, 1280 x 800, 15fps, Acceptable quality(1): 2.9 mbps/3.11 mbps;

 + MPEG4, 1280 x 800, 15fps, Best quality(6): 12.6 mbps/13.2 mbps;
 + MPEG4, 1280 x 800, 15fps, Acceptable quality(1): 1.07 mbps/1.13 mbps.

Acelesi conditii, camera conectata pe WIFi la routerul Linksys WRVS4400N, WPA2:

 + H.264, 1280 x 800, 15fps, Best quality(6): 6.6 mbps/7.2 mbps (imaginea este sacadata, se pare ca nu poate transfera mai mult de 7.2 mbps);
 + H.264, 1280 x 800, 15fps, Acceptable quality(1): 450 kbps/530 kbps(imaginea se misca ok);

Acelesi conditii, camera conectata pe WIFi la routerul Linksys WRVS4400N, fara criptare:

 + H.264, 1280 x 800, 15fps, Best quality(6): 6.5 mbps/7.3 mbps (imaginea este sacadata, se pare ca nu poate transfera mai mult de 7.3 mbps);

Se pare ca limitarea nu este data de criptare, ci de altceva.

Am testat pe WIFI si cu routerul BRICKCOM DWRT 600N (dualband).
Cu setari wifi default (auto channel), la vizibilitate directa a functionat la fel ca  si routerul Linksys.
Mutat in datacenter (obstacole 2 ziduri), routerul BRICKCOM a inceput sa piarda pachete. Setand manual canalul care trebuie ( 😛 ) a remediat problema, routerul BRICKCOM comportandu-se identic cu LINKSYS.

Asadar, WIFI IPCAM se poate, dar in nici un caz cu setarile default :P.
Succes  🙂

 

MPEG4 PT IP DOME Model# 9211PE / 9211PEW

IP Camera

Specificatii:

Camera IP demo pan&tilt, fara zoom.
Exista model cu WIFI si fara.
CD-ul cu soft este UTILITY&USER’S MANUAL IP CAM STD1.10. Nu am putut gasi update-s pe internet, nici siteul producatorului.

Observatii:

Configurarea pe web, default vine cu ip 192.168.0.20 (sau.21).
User root, parola root.

Cam lenesa, daca salveaza fisiere nu mai raspunde la comenzile de PT.

Configurarile de WIFI au fost un calvar, cu greu am pornit-o pe AP-ul Lynksys.
Stie numai WEP.
Pe AP Linksys am putut sa o configurez numai cu WEP, Open system, 64bit, keya numarul 4.

Senzorul este zgomotos.

Este o camera buna pentru vizionare live (manualul specifica maxim 10 clienti simultan, nu am testat inca.

Testele functiei de DVR le-am efectuat atat pe Windows XP SP3, cat si pe NAS Sinology DS211.

Functia de DVR este implementata cam primitiv:  

  • detectia de miscare are maxim 3 zone de miscare, configurabile ca dimensiune
  • dupa definirea zonelor de miscare (“Motion detection”), se configureaza “Event” -> “Add event”).  Aici se poate selecta salvarea filmului pe samba (configurata anterior in “Network” -> “Samba”) sau pe FTP (definit anterior pe “Event server”).
  • partea prosta este ca detectia de miscare se pare ca nu stie sa detecteze si “nemiscarea”. La aparitia evenimentului de miscare se salveaza un film de exact un mega pe FTP sau de exact cat e setat in “Network”->”Samba” pe samba. Am observat ca setarea de 1 Mbyte este prea mica si imposibil de urmarit, probabil ca o setare de 6 Megabytes e acceptabila. Ce nu e acceptabil este ca nu stie sa opreasca inregistrarea cand dispare miscarea.
  • daca e configurata sa salveze imagini, la revedere cu PT-ul. La pan/tilt, camera detecteaza miscare, devine foarte ocupata cu salvarea filmului si nu mai raspunde la comenzile de PT.
  • inregistrarile “pierd” primele cadre de actiune, se pare ca nu are pre-record.
  • la un moment dat, fara un motiv anume (dupa ce a fost miscata mai mult pentru pozitionare, salvare filme activata), a devenit neaccesibila. Am descoperit ca in mod miraculos s-a reinitializat cu setarile de fabrica.
  • cand functioneaza atat WIFI cat shi Ethernet (clase IP diferite, ip-uri multiple pe Windows XP SP3), se intampla “lucruri” in sensul ca nu vede share-ul de samba. Nu am determinat de unde vine problema.

Nu am reusit sa o conectez la aplicatia de Surveillance de pe NAS 🙁