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18 posts
Projects, Linux, networks, systems, finds and internet standards from 2018.
Hannes Mehnert explains TCP in interaction with IP, UDP and ICMP, as well as connection setup, states, teardown, tuning and congestion control. Reliability comes from state machines, timers and feedback rather than from a reliable network. Many apparent application errors can only be explained through TCP states and packet flows.
Read the full postInsecure cloud controls for hot tubs allowed strangers to change temperature, pumps and lighting remotely.
Read the full postKG designs not a solid ball but a growing swarm of independent solar satellites built from dismantled planetary material. Megaprojects become more plausible when modular units replace a rigid overall structure. Automated production can make material and energy more important than human working time.
Read the full postManuel Schmitt reports on the gradual IPv6 rollout for all existing and new web hosting packages and their domains. Since December 2018, all old and new web hosting packages had been reachable via IPv6. The rollout covered all associated domains.
Read the full postJenny List summarises Arsenijs Picugins’ experiences and shows why power supply, connectors, display and enclosure determine portable DIY builds. The ZeroPhone serves as a practical example. Raspberry Pi and BeagleBone are named as possible platforms.
Read the full postA BISSA shoe cabinet holds router, switch, modem, UPS and two Raspberry Pis and still keeps the cabling accessible. The BISSA cabinet cost 25 US dollars. An APC UPS stands in the lower compartment.
Read the full postRFC 8484 encapsulates DNS queries in HTTPS and thereby uses existing web transport and authentication mechanisms. DoH makes path-based observation and classic network diagnostics harder at the same time. Choosing the resolver remains a decision of trust.
Read the full postLutz Donnerhacke reconstructs an apparent firewall failure and finds a time-dependent connection between provider maintenance, DHCP lease and manual reboots. The firewall obtained a DHCP lease with a lifetime of ten hours. The internet interface briefly dropped out at night and then came back.
Read the full postIn 2018 Qualys reported a hole in OpenSSH (CVE-2018-15473) that had existed since the first version in 1999. With prepared packets, attackers could check remotely whether a user name exists, because the server ended the connection differently for valid names. The hole was not considered critical but provided material for targeted password attacks.
Read the full postIn August 2018 the processor flaw Foreshadow, also known as L1 Terminal Fault (L1TF), became known in many Intel CPUs; the Linux main branch and major distributions immediately provided protection. Anyone running third-party virtual machines also had to switch off hyper-threading, which could cost VMs up to 50 percent of their performance. The stable and longterm kernels appeared after less than 24 hours of review.
Read the full postLinux 4.18 appeared in August 2018 with support for USB 3.2 and improved support for the Raspberry Pi 3. Also new were the beginnings of a firewall approach based on eBPF, new graphics drivers and improvements to the live migration of virtual machines. The heise report itself is a short teaser; the details were provided by the Kernel-Log.
Read the full postRFC 8446 defines TLS 1.3 with modern algorithms, forward secrecy and a simplified handshake. RFC 8446 was superseded by RFC 9846. Removing insecure choices improves both security and ease of implementation.
Read the full postDIYP builds an open computer whose tensioned ropes hold the components and turn the technology into a visible design element. The original video has the ID N-z9PidYH4E. The choice of material changes not only the look but also maintenance and airflow.
Read the full postLoRaWAN connects energy-saving sensors over long distances with gateways and central data evaluation.
Read the full postIn January 2018 Lenovo admitted holes in its Fingerprint Manager Pro software, which managed biometric data on computers running Windows 7, 8 and 8.1. The software used a weak encryption algorithm, contained a hard-coded password and was accessible to local users without special rights. Windows 10 was not affected because Windows Hello takes over the function there.
Read the full postIn January 2018 Vodafone Germany CEO Hannes Ametsreiter called for state funding for fibre in order to build a 5G network faster. Until then, funding had mainly gone into copper and DSL expansion. With fibre reaching two percent of households, Germany ranked 28th of 32 OECD countries.
Read the full postAt CES 2018 D-Link and McAfee presented the DIR-2680 router with built-in security functions. It was to cost around 250 US dollars, offer MU-MIMO and support up to 128 clients. There was also virus protection via McAfee’s engine and parental control management via an app.
Read the full postMeltdown countermeasures separated kernel and user memory more strictly but caused additional context switch costs.
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