SarbinBracklur's comments

SarbinBracklur | 5 years ago | on: Gravity batteries try to beat chemical ones with winches, weights, mine shafts

The numbers in this article seem off. 250kW (peak power) for 11s (time at peak power) is 2.75 MJ. That's only about 51 10000mAh D batteries. Of course, the peak power of the gravity battery is much higher than the chemical batteries, but still.

SarbinBracklur | 5 years ago | on: IPv6 Fragmentation Loss

1500 bytes is the de facto standard maximum size of an ethernet frame (not including headers). Therefore, if you want to send data over Ethernet, for example, an IP packet you can typically only send up to 1500 bytes at a time, and if you try to send more it gets dropped. This is called the Maximum Transmission Unit (MTU).

Apparently, their customers were tunneling IP packets through another protocol, meaning that instead of sending an IP packet in a Ethernet frame, they were sending an IP packet in an X packet in an Ethernet frame. Since, like IP and Ethernet packets, the X packets need to contain some information related to the protocol, there was less room for the IP packet. I.e. the MTU was lower.

When you set the MTU on your Operating System (OS), it refers to something slightly different. Instead of "this is the maximum size packet that will fit", it means "assume this is the maximum size packet that will fit". You can use that setting to force your OS to send smaller packets if you know the MTU is lower than your OS thinks.