Business Card AVR Board Updated

November 8, 2008 by Eliot 2 Comments

bcard

Evil Mad Scientist Laboratories has updated their business card AVR breakout boards to version 1.1. We suspect the changes will probably make them even more popular. The boards are designed for the ATmegaXX8 family of microcontrollers. The center has all 28 pins labeled while either end has a prototyping area. An in-system programming header is also provided. For the new version, both prototyping areas have been increased to accommodate DIP14 packages. The holes for the microcontroller are now larger so that they can hold a ZIF socket. Finally, the power and ground traces have been expanded. We’ve always like the versatility of these boards, as demonstrated in the Tennis for Two project, and can’t help wondering if these updates were made to facilitate another project.

Detecting ISP Throttling

June 14, 2008 by Eliot 7 Comments

ISPs have recently become very aggressive towards their customers. They’ve been blocking or altering traffic to prevent you from using specific programs or protocols. Google’s Senior Policy Director recently stated that they’re developing tools to allow people to detect ISP interference. A couple other groups have been building tools as well: The Network Neutrality Squad just released the second beta of their Network Measurement Agent. The tool currently detects spoofed packets by monitoring the round trip time of the connection; early reset packets will have lower than average RTT. If you want to go more in depth, the EFF has published a guide for using Wireshark to do the detection. We’ve even heard rumors of people building tools to tunnel a session inside of one that looks completely different.

[photo: nrkbeta]

Notacon 2008: Last-mile Wireless

April 6, 2008 by Eliot 3 Comments

[Mark Doner] presented on how the WISP he works for near Toledo is set up. His most important point was that 802.11 is garbage when it comes to the type of installations WISPs do. 802.11 expects the clients to adjust based on the traffic from other clients, but when all your clients are directional they won’t see each other. Mark uses Motorola’s Canopy equipment, but he also mentioned Trango and Redline as other vendors. The radios operate in the 5.7GHz band which doesn’t have any power restrictions so they can use refurbished Dish Network dishes when they’re doing long shots. For customers that are nearly at the edge of service, they have 900MHz equipment as well. Heavy fog and freezing rain have proven to be the only weather that really affects the service. For back-haul between their towers they use Dragonwave equipment. Each of the radios costs ~$350 and features GPS to determine distance and maintain sync with the AP. It was interesting to see how a good WISP operates as opposed to the flakey ones we’ve had to deal with in the past.