From NirSoft Freeware
SmartSniff is a network monitoring utility that allows you to capture TCP/IP packets that pass through your network adapter, and view the captured data as sequence of conversations between clients and servers. You can view the TCP/IP conversations in Ascii mode (for text-based protocols, like HTTP, SMTP, POP3 and FTP.) or as hex dump. (for non-text base protocols, like DNS)
SmartSniff provides 3 methods for capturing TCP/IP packets :
1. Raw Sockets (Only for Windows 2000/XP or greater): Allows you to capture TCP/IP packets on your network without installing a capture driver. This method has some limitations and problems.
2. WinPcap Capture Driver: Allows you to capture TCP/IP packets on all Windows operating systems. (Windows 98/ME/NT/2000/XP/2003/Vista) In order to use it, you have to download and install WinPcap Capture Driver from this Web site. (WinPcap is a free open-source capture driver.)
This method is generally the preferred way to capture TCP/IP packets with SmartSniff, and it works better than the Raw Sockets method.
3. Microsoft Network Monitor Driver (Only for Windows 2000/XP/2003): Microsoft provides a free capture driver under Windows 2000/XP/2003 that can be used by SmartSniff, but this driver is not installed by default, and you have to manually
Increased the size of total filter string (Capture Filter and Display Filter) that can be saved into the .cfg file.