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My PhD coping mechanism (or how speaking my mind out loud helps me maintain my sanity)

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Getting a PhD can easily become a lonely where students get depressed, feel out of place, thrown away alone with a mild to a sever sense of the imposter syndrome. There is no wonder that "graduate students are more than six times as likely to experience depression and anxiety as compared to the general population" . Almost all my friends in graduate school face some sort of mental health struggle. This prompted me to write a post on my personal approach to dealing with my own issues and they all have to do with talking. Personally, I find it very hard to talk to strangers, so I focus all my talking to people I know. I talk to different people because defeating imposter syndrome, self doubt, angry thoughts, and most importantly the depression spiral requires multiple perspectives, especially with the highly logical PhD student. Talking with advisors One of the challenges of being a graduate student is feeling at loss when it comes to assessing my own progress, strength

The evolution of Internet routing

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If you ask "how do I get a video from Netflix to my TV screen?" you will probably get a variety of answers depending on whom you ask. Here are a TL;DR of the answers you are most likely to get: the home setting answer "your access point gets the video from the Netflix over the Internet and sends it over wifi to your TV"  the smart apps and video encoding answer "the Netflix app creates an HTTP request specifying your account and some chunks of the video you are about to watch and the Netflix server replies with HTTP responses that contain the chunks" the Internet Protocol (IP) answer "your smart TV creates packets addressed to the Netflix server by its IP address. Based on the IP address, the packets are first sent to the access point which sends it over fiber or telephone landlines to the Internet Service Provider (ISP), like AT&T, the ISP then sends it to other networks which eventually deliver it to Netflix (the ISP can also directly deliv

Extending wpa_supplicant for kernel mac80211 control

wpa_supplicant is a popular cross platform tool for wifi network configuration. On linux kernel, wpa_supplicant can use NetLink ( nl80211 ) to pass commands and arguments to the configuration API of IEEE 802.11 (cfg80211). In this post, I will go through the different edits needed to pass arguments from userspace to mac80211 through wpa_supplicant. I will use my work on WiFi augmentation which allows wpa_supplicant to configure mac80211 to control its medium access control behavior. wpa_supplicant has two main components: wpa_supplicant daemon and the wpa_cli client program. The edits I will present will be in both the daemon and the client. My edits assumes the existence of some functions in kernel that the user of wpa_supplicant is attempting to invoke. The edit starts with the wpa_cli (client) code. The wpa_cli code maintains an array of all commands it can process mapped to callback functions that should be executed on the invocation of that command. The array can be found at