A transit card, a hotel key, a payment tap, a pet's microchip — none of them has a battery, yet all of them send data to a reader on demand. They do it by stealing energy from the reader's own field and whispering back by changing how much of it they absorb. This is the physics and the security of the tag.
Wireless
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RFID and NFC: How Powerless Tags Talk Back -
LoRaWAN for Long-Range IoT LoRaWAN sells itself as kilometers of range from a coin cell, and the pitch is true — but only because chirp spread spectrum trades bandwidth and airtime for link budget in ways most builders never think through. This post walks the CSS modulation, the spreading-factor and airtime math, the star-of-stars architecture, duty-cycle regulations, and where LoRaWAN genuinely beats Wi-Fi and cellular versus where the marketing outruns the physics.
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Wi-Fi 7 and Multi-Link Operation Wi-Fi 7's headline number is 46 Gbps, but the feature that actually changes how your network behaves is Multi-Link Operation. We separate the marketing from the physics: 320 MHz channels, 4096-QAM, the MLO modes nobody explains clearly (STR, eMLSR, eMLMR), why latency and reliability matter more than peak throughput, and what any of it does for a real home network in 2026.
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How Cell Networks Actually Work: 1G to 5G From analog FM and the 1947 Bell Labs cellular concept to massive MIMO and network slicing — what each generation actually changed in the air interface, how handoffs work at 70 mph, what a SIM really is, and why 5G coverage maps still disappoint.
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CCNA: Wireless Networking Fundamentals 802.11 wireless standards from a/b/g through Wi-Fi 6E and 7, 2.4/5/6 GHz channel planning, BSS/IBSS/ESS topologies, WPA2 vs WPA3 security, autonomous vs lightweight AP architectures, and basic Cisco WLC configuration — CCNA-level coverage.