It's easy to capture packets with Wireshark, the world's most popular network sniffer, whether off the wire or from the air. But how do you use those packets to understand what's happening on your network? With an expanded discussion of network protocols and 45 completely new scenarios, this extensively revised second edition of the best-selling Practical Packet Analysis will teach you how to make sense of your PCAP data. You'll find new sections on troubleshooting slow networks and packet analysis for security to help you better understand how modern exploits and malware behave at the packet level. Add to this a thorough introduction to the TCP/IP network stack and you're on your way to packet analysis proficiency. Learn how to: Use packet analysis to identify and resolve common network problems like loss of connectivity, DNS issues, sluggish speeds, and malware infections Build customized capture and display filters Monitor your network in real-time and tap live network communications Graph traffic patterns to visualize the data flowing across your network Use advanced Wireshark features to understand confusing captures Build statistics and reports to help you better explain technical network information to non-techies Practical Packet Analysis is a must for any network technician, administrator, or engineer. Stop guessing and start troubleshooting the problems on your network.