Network Guy

Today I will show you how to configure QoS for outgoing SIP VoIP traffic who goes throw a VPN tunnel / crypto-map. To solve this we need to create class-maps for all IP traffic and for our SIP traffic and bind them to the crypto map and the outgoing interface because VPN traffic is encapsulated … Read more

If you accidentally erased your flash or have a Cisco router with an empty flash, you can upload an IOS image from ROMmon to recover the device to a functional router. Connect your router via console-cable to a PC and use PuTTY to connect to your device. I use TFTPD32 from Philippe Jounin. When starting … Read more

You bought a used Cisco router at eBay configured with a password? You loose your password but still need the current configuration? No Problem! You can easily reset the configuration/passwords. You need to connect to the serial port of the Cisco router. I’m using always a USB-RS232-serial-adapter and PuTTY for this. To boot your router … Read more

In Germany some internetprovider doesn’t offer a static WAN IP address. So the easiest way to connect a branch office router via IPsec VPN protocol to the central network address is using a Cisco EasyVPN connection with network-extension mode. In this example we have two networks: The IP subnet of our mainoffice is 192.168.1.0 /24 … Read more

One of my customers has a separated network within their internal network. Mobile devices (Android Phones, iPhones, etc.) are connected to a consumer access point which is connected behind the Cisco Router 876:       The Traveler service is also rechable via internet (configured with PAT pointed to the Traveler server). In the past, … Read more