Tag: pdu

Cross-compile your own TcpDump tool

Foreword Everyone must have heard or used network packet capture tools, such as the powerful WireShark, which supports Window and Linux platforms; and the TcpDump command line tool for Linux systems. As an embedded development engineer, during the development process, it is inevitable that there will be no graphical interface. Under the Linux system, you […]

Linux commands (11) – tcpdump

? ? Article directory 1. Introduction to commands 2. How to use 3. Command options 4. Basic grammar and usage 1. Display ASCII string 2. Capture data of specific protocols 3. Capture data from a specific host 4. Write the captured data to a file 5. Line buffering mode 5. Understanding the output of tcpdump […]

38 | Case: How to use tcpdump and Wireshark to analyze network traffic?

In the previous section, we learned how to analyze and optimize DNS performance problems. To briefly review, DNS can provide the mapping relationship between domain names and IP addresses, and is also a commonly used global load balancing (GSLB) implementation method. Usually, services that need to be exposed to the public network will be bound […]

02 | A preliminary study on packet capture analysis technology: Can you use tcpdump and Wireshark?

The core content of this course is probably packet capture analysis. Among the many troubleshooting technologies, packet capture analysis can be said to be the “crown jewel”, and it is also the direction in which many people have been working hard. Therefore, I don’t need to mention the position of these two tools, tcpdump and […]

RSTP, MSTP spanning tree protocol edge port, BPDU protection configuration

RSTP experiment: Experimental steps: 1. Configure vlan and interface type on the switch so that PC1 can ping pc2. 2. Modify the switch priority [SW1]stp priority 4096 3. Modify the switch spanning tree mode to RSTP[SW1]stp mode rstp 4. Configure the e/0/0/3 interface as an edge interface and observe the convergence speed. [SW1-Ethernet0/0/3]stp edged-port enable […]

Let’s talk about the wonderful uses of tcpdump in detail

Original address: EMC Chinese Support Forum https://community.emc.com/go/chinese Introduction The tcpdump command was originally designed to observe TCP/IP performance problems. It is a tool for intercepting network packets and outputting the contents of the packets. tcpdump can completely intercept the headers of data packets transmitted in the network and provide analysis. It supports filtering for network […]

Packet capture and analysis of Unix Domain Socket through tcpdump

Original text: https://plantegg.github.io/2018/01/01/Capture and analyze Unix Socket packets through tcpdump/ Background introduction Most of the time we can use tcpdump to capture network packets and analyze request and response data to troubleshoot problems. However, if the program is accessed through Unix Domain Socket, then tcpdump cannot see the specific content flowing in the Unix Domain […]

[tcpdump] Network communication debugging – tcpdump usage guide

Install tcpdump Installation command under Ubuntu: sudo apt install tcpdump Arm embedded linux: Download the tcpdump source code package, compile it using the cross-compilation chain and put it into the Arm board (tcpdump download and cross-compilation process to be added) Introduction to tcpdump command format tcpdump syntax: tcpdump [ -AdDefIJKlLnNOpqRStuUvxX ] [ -B buffer_size ] […]

Android hid sends apdu format data

In Android, if you want to send data in APDU format via HID (Human Interface Device), this usually involves a USB HID device or a Bluetooth HID device. The HID protocol is typically used with keyboards, mice, and other input devices rather than communicating directly with smart cards. However, if your device supports USB HID […]