Monday, June 29, 2009

NetScanTools (TM) Pro 10.92 Published

This release added a powerful new feature to Ping - Enhanced: TCP Ping. TCP Ping uses either a SYN or ACK packet to 'ping' a target and it looks for a response back. If it gets a response, it shows the timing with submillisecond resolution. In this case the timing you are seeing is TCP Latency because you are seeing a TCP response to a TCP packet. Our TCP Ping gives you control over the TCP header. You can set the Distributed Services Code Point bits and the ECN bits to see what effect they have on packet delivery between two points. You can also set the Sequence, Window and Acknowledgement fields in the TCP header to whatever you want. AutoPing was renamed Continuous Ping and we also added Autosave mode so that all the ping results can be saved to a file. This file has tabbed delimited columns so that you can easily import the results into a spreadsheet. This is one of the most complete Ping tools on the market giving you instant access to all three modes of operation: ICMP, UDP and TCP Ping.

Other changes include the addition of the Distributed Services bits to Packet Generator, additional information added to whois IP address queries, improvements to Traceroute and TTCP. Graphical Ping can now send packets as large as 4095 bytes.

10.92 is available now and is ready for download by current registered users. USB version 10.92 will be available in the next day or two.

Thursday, June 25, 2009

ARP Scan versus Ping Sweep

Today I had a user ask me what the difference was between ARP Scan and Ping Sweep (NetScanner) and why he gets different results when running them on his 192.168.0.x subnet.

Here was my answer:

There is a difference between ARP Scan and Ping Sweep. When you do an ARP Scan of a subnet, all devices that communicate with IPv4 on that subnet must respond to ARP packets. If they don't respond they cannot communicate with any other machine. This even applies to devices that are running firewalls and do not respond to ICMP echo request packets (ping packets).

When you use Ping Sweep on that same subnet, you are sending ICMP echo request packets to every device. If the device (computer) is running a third party 'personal' firewall or even something like the built-in Windows Firewall, it may not respond depending on the firewall settings. So you will see fewer devices respond with Ping Sweep than with ARP Scan.

They both have their uses because ARP Scan does not work once it crosses a router to another subnet or WAN. ICMP packets generated by Ping Sweep are routed unless deliberately blocked, even across the internet.

Tuesday, June 2, 2009

NetScanTools (TM) Pro 10.91 Published

Both the installed version and the USB version are ready at the same time -- amazing! The changes are relatively minor if you are using an English version of Windows, but if you are using a non-English European version, this release has potentially big changes. If your C:\documents and settings\%username%\application data\nwps\netscantoolspro (XP/2000/2003) path has non-English characters in it, the paths to the database files might not have been understood properly by SQLite, so you would not be able to open the SQLite databases. This has been fixed.

The second major thing affects those who need to place the files normally found in those two paths somewhere else, maybe for a virtual machine. We've added a way to use an .ini file to describe new paths to those files.

There are also some other small changes and as usual we've updated the databases. Whois now supports several more top level domains and there were two corrections to existing domains -- like .mil whose whois server went offline a while ago.

If you have 10.x and your maintenance plan is active, please use Check for New Version to get the latest version.

And don't forget to look at http://www.netscantools.com/ once in a while for periodic sales. Right now there is a 2 for 1 sale, a USB and CDROM license for the price of the USB.