Understanding Cisco Access Point IOS Images

Introduction

All Cisco Aironet wireless access points and bridges were shipped in general with an IOS Software.
The only exception is the OEAP602.

Note:Some older Cisco access points did not run IOS, such as the Aironet 340 which ran only VxWorks, and the 1000 series lightweight APs.
Access Point IOS is distributed as a tar file. These tar files can be downloaded from cisco.com SDS; lightweight IOS images (k9w8) are also bundled in
the WLC software images (.aes). The IOS image names include the following components. Continue Reading →

Repair a corrupted IOS Image on a LWAPP

Introduction

Here i would like to describe, how to set an access point to factory default.
My prefered manner is to formatting the flash of an access point,
copy the IOS Image from a tftp server and extract the tar file.
You need to execute some special command to extract the tar file.
If you copy only the tar file to the flash, it doesn’t work and the access point are not able to boot from the image. Continue Reading →

Wireshark general

Wireshark is a free and open-source packet analyzer. This tool is used for network troubleshooting, analysis,
communication and software protocol development and education. The original software were named Ehtereal, in May 2006.
Later it was renamed to Wireshark due to trademark issues.

Wireshark uses pcap to capture packets. It runs on several platforms like GNU/Linux, OS X, BSD, Solaris,
some other Unix-like operating systems, and Microsoft Windows.
There is also a terminal-based version (non-GUI) called TShark.

Here I’d like to introduce some important filter options in wireshark.
It’s very hard to find exactly the right packets, you are looking for, in a hugh amount of data.

The following charts are a compendium of several websites.
My aim for these post was, to bring the most important commands of one page.
&nb
Wireshark Homepage

Continue Reading →

Understanding VLAN Trunk Protocol

1. Introduction

Vlan Trunk Protocol (VTP) reduces administrative effort in a switched network.
There are 3 different types of vtp operating modes.

• Server
• Client
• Transparent

Continue Reading →