In5G NRbyEventHelix·Oct 28A 5G NSA phone never attaches to 5G: reading an EN-DC attach from a real captureIn 5G Non-Standalone (Option 3, or EN-DC), there is no 5G core. The UE attaches to the 4G EPC through an LTE anchor eNB, and 5G arrives…
InSoftware DesignbyEventHelix·Oct 14Tidally Locked Does Not Mean Motionless: Designing Orbits Around Proxima bStand in Proxima b's habitable zone, and the star rests on the horizon. It does not rise or set. Noon and midnight are not times here; they…
In5G NRbyEventHelix·Oct 9Two retransmissions, zero losses: RLC-NR acknowledged mode in a real 5G captureA real 5G NR attach capture shows the radio link sending the same RLC packet twice, on two separate occasions. Not one status report in the…
InSoftware DesignbyEventHelix·Oct 1An Alien AI’s RFP: an LLM in OrbitTerminus, a series between science fiction and system design
InTCP/IP NetworkingbyEventHelix·Sep 29Ask AI to Annotate a Wireshark PCAPOne prompt, 33 captioned packets — AI-annotating a DNS capture
In5G NRbyEventHelix·Sep 16Reading MAC-NR in a 5G captureSame link, same rules, same capture: over 144 frames of one 5G NR MAC session, the uplink threw away 30,955 bytes on padding, and the…
In5G NRbyEventHelix·Sep 15One 5G frame, two security contexts — reading a decrypted NR attachA 5G radio capture can be encrypted twice over, by two separate networks holding two different sets of keys. Wireshark work-item 19757…
In5G NRbyEventHelix·Sep 14Reading an IMS voice call out of a GTP-only 5G captureAn srsRAN bug report describes a capture taken on a 5G base station’s F1-U interface that decodes as nothing but GTP. The SIP signaling and…
In5G NRbyEventHelix·Sep 3F1-U flow control: how a 5G base station’s two halves stay in stepIn 5G, the gNB is not a single box. Under the 3GPP higher-layer split (TS 38.401), a Central Unit owns the upper radio-protocol layers, and…
In5G NRbyEventHelix·Aug 12Reading a 5G CU/DU registration frame by frame, over F1APIn 5G, the gNB is not a single box. Under the 3GPP higher-layer split (TS 38.401), it divides into a Central Unit (CU) that owns the upper…
