Random thoughts

I got an Edimax IC-7110W IP camera a nd I liked their firmware, but I was curious what was happening behind the curtains , so I decided to take a look. Step 1: Get the firmware - I got the firmware update binary package from the ir site for version 1. 7 - other ve rsions are probably similar: http://www.edimax.com/en/support_detail.php?pd_id=415&pl1_id=8 Step 2: Prepare your environment - I am using Ubu ntu Linux 12.04 . You will need to do wnload and install the following softw are: a build env ironment (gcc, g++, make , tar, zlib1g-dev, tar, gzip) firmware -mod-kit: http://bitsum.com/firmware_mod_kit.htm subversion ( sudo apt-get install subversion ) Step 3: Install firmware-mod-kit and compile binwalk and unsquashfs: adrianp@frost: ~/temp$ mkdir - p edima x /1.7 edimax/fmk adrianp@frost: ~/temp$ cd edimax adrianp@frost: ~/temp/edimax$ svn checkout http://firmware-mod-kit.googlecode.com/svn/trunk/ fmk ... output omitted ... adrianp@frost: ~/temp/edimax$

I have an IP Camera that supports RTSP streaming (most IP cameras seem to support it - Axis, Edimax, etc). This allows you to view mpeg4 or h264 live streams either by using a proprietary ActiveX control (via their web interface) or via a RTSP client. If you are in the same LAN as the camera, you can easily connect to it by using VLC or even ffmpeg (to save or transcode the stream): vlc rtsp://192.168.1.10/ipcamera_h264.sdp ffmpeg -i rtsp://192.168.1.10/ipcamera_h264.sdp test.ts ffmpeg -i rtsp://192.168.1.10/ipcamera_h264.sdp -f mpegts | vlc - The problem is if you want to access that camera over the Internet. RTSP usually transports the data over UDP and negotiates the UDP ports over a control session on port 554 TCP. This gets difficult if you use NAT at either end or if you have firewalls you need to get through. Let's consider this typical scenario: The packets need to go through 2 NATs to travel between the source and destination. To make this happen, y