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during one of the design discussions with one of our Customers, I had a chance to discuss a bit about using anycast to scale out delivery via CDN. unfortunately, as more ads served even on popular sites is malware or even miners for different cryptocoins it begs a question - how should you protect the site you’re maintaining? using reputable CDN is good first step. the other one, i didn’t know about (and it seems to be quite natural if you think about it) is to verify hash of the attached resources. this can give you powerful tool to verify and then take an action before page is loaded to verify images or for example JavaScript. ...

6:51 AM, 30 APRIL 1975: SWIFT 22 IS OUTBOUND WITH 11 PAX ON BOARD INCLUDING THE LZ COMMANDER. ALL THE AMERICANS ARE OUT REPEAT OUT. this traditionally short message from NSA signals intelligence, was everything that was needed to confirm that all US citizens left US embassy in Saigon. Saigon changed name to Ho Chi Minh a day later, taken over by North Vietnam army. signals intelligence changed significantly from that time, but the book i’m writing about right now was published way before Snowden era. James Bamford Body of secrets describes in amazing details last 60 years of NSA backstage operations. ...

jeden z moich znajomych zauważył bardzo celnie, że mam często ‘krótki lont’. nie mogę się nie zgodzić - czasami tak po prostu jest. zrozumienie i opanowanie tego to katorżnicza praca, która w dodatku wymaga codziennego szlifowania umiejętności. każdy kto próbował - wie. na wielu poziomach ten temat dotyka zagadnień dominujących dzisiejsze tzw. szkoły biznesu - jak zbudować zespół, jak jego członkowie powinni wzajemnie się uzupełniać, motywować i jednocześnie - zachęcać do wartościowej pracy. ...

my whole summer vacation this year is a week by the sea. however, I was able anyway to catch up my reading backlog from last few weeks - books put aside and waiting patiently in their queue. so let’s go faster this time, but through the whole list: Matthew Syed - The black box method - a great book describing the process of correcting errors; it starts with aviation, which over the last decades has led to a dramatic increase in flight safety. then we are moving to medicine and other sectors. methodical research, inference and drawing conclusions, sometimes contrary to incumbent ’experts’, allows not only to increase security but also to push our understanding of reality and facts forward. great book. ...

have you thought recently how oversubscribed are acronyms you’re using daily if you’re in IT? i just spent the whole day listening about VPC, but not vPC or VPC - but about Virtual Private Cloud in AWS services. not about virtual Private Channel or Virtual Path Connection and neither about Virtual Packet Core. and i have to admit, i liked it. i’ve spent whole day on a Mirek Burnejkos training dedicated to clouds. as Robert Ślaski was preaching on recent PLNOG - every respectable network engineer should have good idea how cloud works, and what are capabilities of different providers - like AWS or Azure. that’s the way todays IT and OT world looks like. the better you are about understanding specifics, the better you’ll be at positioning them in your real-life projects. and advice to users or customers. ...

my old poor LSI 9211-8i RAID card, that was powering my cache NAS server, decided to die. my spare 9261-8i, to my complete suprise, was halting FreeNAS at the boot… and i was not able initially to troubleshoot the problem. it was dropping mysterious timeout errors: mfi0: COMMAND 0xfffffe000150dc08 TIMEOUT AFTER 59 SECONDS mfi0: COMMAND 0xfffffe000150dc90 TIMEOUT AFTER 59 SECONDS mfi0: COMMAND 0xfffffe000150dc18 TIMEOUT AFTER 59 SECONDS run_interrupt_driven_hooks: still waiting after 60 seconds for xpt_config my google-fu immediately shown me some potential solutions, but they were totally random nad kind of voodoo-magic (‘disable Firewire controller!’, ‘disable ATA controller!’… and so on). also, i tried to upgrade firmware version, downgrade it… the problem was still there. ...

after being absent on three PLNOG editions, i finally made it to the conference and to agenda. my presentation slides are here. i tried to cover everything important from networking perspective starting from IMP and ending on NPU, reprogrammable ASICs and what’s lurking in the future. of course if you’ll vote by your surveys, i hope to get back to delivering presentations. what’s interesting is that Krzysztof Kania also picked up architectural topics in his article about first routers - go read! ...

some of us know it better, some worse, and the rest haven’t heard or thought about it (or claims “i don’t need it”) work ‘in the zone’ got popular immediately after world ended being enchanted by open spaces and mandatory offices, and got back to using rooms or - in XXI century - in “home offices”. the fact that giants like Facebook or Apple still build huge offices and promote unconstrained mobility, availability and capability to forget about home given work is the most important thing you can do (hence “socializing” is as well), doesn’t change too much. most of us fares better when we can isolate ourselves from noise and constant interruptions (not to mention all kind of viruses, so proficiently distributed in todays offices by AC). ...

during the last 30 years, processor speeds has increased from millions of cycles to billions - multiplied by multi-core and special mechanisms that increase the efficiency of working with ‘boring’ cores. Pentium 66 processor from 1993 contained 3.2 million transistors, which is anyway quite a value, considering they are packed into a space comparable to that of four dices - and contains one main unit. available today Xeon E5-2699v4 has 22 cores operating at nominal frequency 2.2GHz clock and 7.2 billion transistors. ‘imagine that’! ...