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  92. <meta itemprop='author' content='Bob Cromwell'>↩
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  114. <h1>Computer System and Network Security</h1>↩
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  126. ↩
  127. <h2 class="centered"> Cybersecurity </h2>↩
  128. ↩
  129. <p>↩
  130. <strong>Cybersecurity becomes more important every year,↩
  131. as we rely more and more on the world-wide↩
  132. Internet in government, business, and our↩
  133. private lives.</strong>↩
  134. <br><br>↩
  135. Everyone needs to know how to be safe enough in their↩
  136. personal email and web browsing.↩
  137. Start with my↩
  138. <a href="/cybersecurity/basics/">introductory page</a>↩
  139. if you're new to cybersecurity.↩
  140. <br><br>↩
  141. Certifications are the coin of the realm nowadays,↩
  142. and they're the main reason many people come to this page.↩
  143. And so, here's my guidance on preparing and passing the exams:↩
  144. </p>↩
  145. ↩
  146. <div class="row centered" style="max-width:60em;">↩
  147. ↩
  148. <div class="col-12 col-md-4">↩
  149. <a href="/cybersecurity/comptia/" class="btn btn-block btn-danger btn-lg">↩
  150. Study guide for <br> CompTIA Security+</a>↩
  151. </div>↩
  152. ↩
  153. <div class="col-12 col-md-4">↩
  154. <a href="/cybersecurity/isc2-cissp/" class="btn btn-block btn-danger btn-lg">↩
  155. Study guide for <br> (ISC)<sup>2</sup> CISSP</a>↩
  156. </div>↩
  157. ↩
  158. <div class="col-12 col-md-4">↩
  159. <a href="/cybersecurity/isc2-ccsp/" class="btn btn-block btn-danger btn-lg">↩
  160. Study guide for <br> (ISC)<sup>2</sup> CCSP</a>↩
  161. </div>↩
  162. ↩
  163. <div class="col-12">↩
  164. <a href="/cybersecurity/exam-language-tricks/" class="btn btn-block btn-danger btn-lg">↩
  165. How To Defeat the Language Tricks↩
  166. (ISC)<sup>2</sup> and CompTIA Use↩
  167. to Unfairly Lower Your Score</a>↩
  168. </div>↩
  169. ↩
  170. </div>↩
  171. ↩
  172. <p>↩
  173. The rest of these pages provide background for the courses↩
  174. I write and teach.↩
  175. They list the references and URLs for various tools,↩
  176. studies, news reports, and other things that come up↩
  177. in courses.↩
  178. I use these pages myself, so I don't have to try to↩
  179. memorize URLs and other reference details!↩
  180. <br><br>↩
  181. Here's that starting point:↩
  182. </p>↩
  183. ↩
  184. <p class="centered">↩
  185. <a href="/cybersecurity/basics/" class="btn btn-lg btn-info btn-block">↩
  186. <strong>Cybersecurity Basics</strong> <br>↩
  187. How to stay safe online</a>↩
  188. </p>↩
  189. ↩
  190. <p class="canvased textright" style="margin-top:5px;">↩
  191. <strong><em>Few persons can be made to believe that↩
  192. it is not quite an easy thing to invent a↩
  193. method of secret writing which shall baffle↩
  194. investigation.↩
  195. Yet it may be roundly asserted that human↩
  196. ingenuity cannot concoct a cipher which↩
  197. human ingenuity cannot resolve.</em></strong>↩
  198. <br>&mdash; Edgar Allan Poe, in "A Few Words On↩
  199. Secret Writing", <em>Graham's Magazine,</em>↩
  200. July 1841↩
  201. </p>↩
  202. ↩
  203. <div class="centered cb">↩
  204. <ins class="adsbygoogle responsive"↩
  205. style="display:block;"↩
  206. data-full-width-responsive="true"↩
  207. data-ad-client="ca-pub-5845932372655417"↩
  208. data-ad-slot="4849215406"></ins>↩
  209. <script>↩
  210. (adsbygoogle = window.adsbygoogle || []).push({});↩
  211. </script>↩
  212. </div>↩
  213. ↩
  214. <nav>↩
  215. <h2> Fundamentals &mdash; Cryptography and Networking</h2>↩
  216. ↩
  217. <div class="row centered">↩
  218. ↩
  219. <div class="col-12 col-md-7 col-lg-6">↩
  220. <table>↩
  221. <tr>↩
  222. <td style="width:50%;">↩
  223. <img src="pictures/enigma-7615.jpg"↩
  224. alt="German Enigma encryption machine, three rotors, open with rotors exposed."↩
  225. class="bordered captioned" loading="lazy">↩
  226. </td>↩
  227. <td style="width:50%;">↩
  228. <img src="pictures/sigaba-7618.jpg"↩
  229. alt="U.S. SIGABA encryption machine."↩
  230. class="bordered captioned" loading="lazy">↩
  231. </td>↩
  232. </tr>↩
  233. <tr>↩
  234. <td class="caption" colspan="2"↩
  235. style="background:#c0c0c0;↩
  236. font-size: 85%;↩
  237. margin-top:0; padding-top:0;↩
  238. max-width: 414px;">↩
  239. World War Two cryptographic hardware<br>↩
  240. <strong>Left:</strong> German Enigma encryption machine <br>↩
  241. <strong>Right:</strong> U.S. SIGABA encryption machine <br>↩
  242. National Museum of the U.S. Air Force, WPAFB↩
  243. </td>↩
  244. </tr>↩
  245. </table>↩
  246. <div class="centered">↩
  247. <a href="https://amzn.to/3Oxrs7B">↩
  248. <img src="/amazon-pictures/amzn-dark-territory.jpg"↩
  249. alt="Dark Territory: The Secret History of Cyber War"↩
  250. class="bordered captioned" loading="lazy"></a>↩
  251. <br><span class="badge badge-pill badge-primary">↩
  252. Amazon 1476763267</span>↩
  253. </div>↩
  254. </div>↩
  255. ↩
  256. <div class="col-12 col-md-5 col-lg-6">↩
  257. <a href="/cybersecurity/crypto/" class="btn btn-block btn-info">↩
  258. <strong>Just Enough Cryptography</strong><br>↩
  259. <em>↩
  260. Cryptographic algorithms,↩
  261. digital signatures,↩
  262. cryptographic hashes,↩
  263. the basics of how they work</em></a>↩
  264. <a href="/cybersecurity/crypto-flowcharts.html" class="btn btn-block btn-info">↩
  265. <strong>Cryptography Flowcharts</strong></a>↩
  266. <a href="/cybersecurity/cipher-selection.html" class="btn btn-block btn-info">↩
  267. <strong>Selecting an Encryption Cipher and Mode</strong></a>↩
  268. <a href="/cybersecurity/elliptic-curve-cryptography/" class="btn btn-block btn-info">↩
  269. <strong>How Elliptic-Curve Cryptography Works</strong></a>↩
  270. <a href="/cybersecurity/how-rsa-works.html" class="btn btn-block btn-info">↩
  271. <strong>How RSA Works</strong></a>↩
  272. <a href="/cybersecurity/verify-digital-signature.html" class="btn btn-block btn-info">↩
  273. <strong>How to Verify Digital Signatures</strong></a>↩
  274. <a href="/networking/" class="btn btn-block btn-info">↩
  275. <strong>TCP/IP</strong> &mdash;↩
  276. How the networking protocols work</a>↩
  277. <a href="/networking/routing.html" class="btn btn-block btn-info">↩
  278. <strong>How Does IP Routing Work?</strong></a>↩
  279. <a href="/networking/nat.html" class="btn btn-block btn-info">↩
  280. <strong>How Does NAT Work?</strong></a>↩
  281. <a href="/networking/what-is-ipsec.html" class="btn btn-block btn-info">↩
  282. <strong>A simple explanation of IPsec</strong><br>↩
  283. <em> What IPsec is,↩
  284. what network security it provides,↩
  285. how it builds a VPN,↩
  286. how to set it up</em></a>↩
  287. <a href="/cybersecurity/crypto/hash-search.html" class="btn btn-block btn-info">↩
  288. <strong>Are all hash outputs possible?</strong></a>↩
  289. </div>↩
  290. ↩
  291. </div>↩
  292. ↩
  293. <div class="centered cb">↩
  294. <ins class="adsbygoogle responsive"↩
  295. style="display:block;"↩
  296. data-full-width-responsive="true"↩
  297. data-ad-client="ca-pub-5845932372655417"↩
  298. data-ad-slot="4849215406"></ins>↩
  299. <script>↩
  300. (adsbygoogle = window.adsbygoogle || []).push({});↩
  301. </script>↩
  302. </div>↩
  303. ↩
  304. <p class="canvased textright" style="margin-top:5px;">↩
  305. <strong><em>We will bankrupt ourselves in the vain search↩
  306. for absolute security.</em></strong>↩
  307. <br>&mdash; Dwight D. Eisenhower↩
  308. </p>↩
  309. ↩
  310. <h2 class="centered">Information Security</h2>↩
  311. ↩
  312. <div class="row centered">↩
  313. <div class="col-12">↩
  314. <a href="/cybersecurity/privacy.html" class="btn btn-block btn-info">↩
  315. <strong>Confidentiality and↩
  316. Data Integrity Tools</strong><br>↩
  317. <em> PGP &amp; Gnu Privacy Guard,↩
  318. Key Recovery,↩
  319. RADIUS,↩
  320. Risks of Google,↩
  321. Sanitizing Media,↩
  322. Secure Online Data Storage,↩
  323. Information Leakage,↩
  324. Commercial Cryptography,↩
  325. SSH, Secure FTP,↩
  326. Hardware Encryption,↩
  327. Voice Scramblers,↩
  328. Cryptography and International Law,↩
  329. X Privacy and <code>xspy</code>,↩
  330. IPSec,↩
  331. VPN's,↩
  332. Key Loggers,↩
  333. Spyware</em></a>↩
  334. </div>↩
  335. ↩
  336. <div class="col-12 col-md-5">↩
  337. <a href="/cybersecurity/regulations.html" class="btn btn-block btn-info">↩
  338. <strong>Government and Industry Regulations</strong><br>↩
  339. <em>HIPAA, Sarbanes-Oxley (Sarbox/SOX),↩
  340. PCI DSS (Payment Card Industry↩
  341. Data Security Standard)</em></a>↩
  342. </div>↩
  343. <div class="col-12 col-md-7">↩
  344. <a href="/cybersecurity/backdoors.html" class="btn btn-info">↩
  345. <strong>Backdoor Problems</strong><br>↩
  346. <em>Government-imposed backdoors make↩
  347. security much worse for↩
  348. individuals, businesses,↩
  349. and the government itself</em></a>↩
  350. </div>↩
  351. ↩
  352. </div>↩
  353. ↩
  354. <div class="row centered">↩
  355. ↩
  356. <div class="col-12 col-md-6 col-lg-4">↩
  357. <a href="/cybersecurity/surveillance.html" class="btn btn-block btn-info">↩
  358. <strong>Government Surveillance</strong><br>↩
  359. <em>US and other government surveillance,↩
  360. PRISM&nbsp;/↩
  361. US-984XN&nbsp;/↩
  362. XKeyscore&nbsp;/↩
  363. Boundless Informant↩
  364. programs,↩
  365. backdoors and weaknesses</em></a>↩
  366. </div>↩
  367. ↩
  368. <div class="col-12 col-md-6 col-lg-3">↩
  369. <a href="/cybersecurity/availability/" class="btn btn-block btn-info">↩
  370. <strong>Availability Tools</strong><br>↩
  371. <em>Remote and local archiving,↩
  372. Real costs of data loss,↩
  373. Laptop theft prevention,↩
  374. Fighting spam</em></a>↩
  375. </div>↩
  376. ↩
  377. <div class="col-12 col-md-6 col-lg-3">↩
  378. <a href="/cybersecurity/availability/destruction.html" class="btn btn-block btn-info">↩
  379. <strong>Data Destruction</strong><br>↩
  380. <em>Overwriting digital storage,↩
  381. Destroying physical media</em></a>↩
  382. </div>↩
  383. ↩
  384. <div class="col-12 col-md-6 col-lg-2">↩
  385. <a href="/cybersecurity/availability/ddos.html" class="btn btn-block btn-info">↩
  386. <strong>DDOS</strong><br>↩
  387. <em>Distributed denial of service</em></a>↩
  388. </div>↩
  389. ↩
  390. </div>↩
  391. ↩
  392. <div class="row centered">↩
  393. ↩
  394. <div class="col-12 col-md-6 col-lg-3">↩
  395. <a href="/cybersecurity/availability/storage-longevity.html" class="btn btn-block btn-info">↩
  396. <strong>Storage Longevity</strong><br>↩
  397. <em>Media longevity and failure rates,↩
  398. Format longevity</em></a>↩
  399. </div>↩
  400. <div class="col-12 col-md-6 col-lg-3">↩
  401. <a href="/cybersecurity/availability/cloud-archiving.html" class="btn btn-block btn-info">↩
  402. <strong>Cloud Archiving</strong><br>↩
  403. <em>Google Coldline, AWS Glacier,↩
  404. Cloud archiving tools</em></a>↩
  405. </div>↩
  406. ↩
  407. <div class="col-12 col-lg-6">↩
  408. <a href="/cybersecurity/forensics.html" class="btn btn-block btn-info">↩
  409. <strong>Computer Forensics</strong><br>↩
  410. <em>Free tools for forensics and↩
  411. recovering deleted pictures from↩
  412. camera memory,↩
  413. file system forks and↩
  414. Alternate Data Streams,↩
  415. EFS and forensics</em></a>↩
  416. </div>↩
  417. ↩
  418. <div class="col-12">↩
  419. <a href="/cybersecurity/mobile-phone-security/" class="btn btn-block btn-info">↩
  420. <strong>Minimize the Impact of↩
  421. Smart Phone Loss or Theft</strong><br>↩
  422. You can't prevent such an event,↩
  423. but you can creatly minimize its impact by↩
  424. configuring and using your phone in↩
  425. safer ways</a>↩
  426. </div>↩
  427. ↩
  428. </div>↩
  429. ↩
  430. <p class="canvased textright" style="margin-top:5px;">↩
  431. <strong><em>Treat your password like your toothbrush.↩
  432. Don't let anybody else use it,↩
  433. and get a new one every six months. </em></strong>↩
  434. <br>&mdash; Clifford Stoll↩
  435. </p>↩
  436. ↩
  437. <h2 class="centered">User Authentication</h2>↩
  438. ↩
  439. <div class="row centered">↩
  440. <div class="col-12">↩
  441. <strong>Passwords &mdash; How they work,↩
  442. how to break them,↩
  443. and the alternatives</strong><br>↩
  444. <div class="row centered">↩
  445. <div class="col-12 col-md-4">↩
  446. <a href="/cybersecurity/password.html" class="btn btn-block btn-info">↩
  447. <strong>1: How passwords work:</strong>↩
  448. processing and storage,↩
  449. salt values,↩
  450. hashes and entropy</a>↩
  451. </div>↩
  452. <div class="col-12 col-md-8">↩
  453. <a href="/cybersecurity/password-breaking.html" class="btn btn-block btn-info">↩
  454. <strong>2: Breaking passwords:</strong>↩
  455. analysis of↩
  456. authentication strength of various↩
  457. operating systems, dictionary attacks,↩
  458. cracking attacks, Rainbow Table attacks,↩
  459. frequent password changes and the↩
  460. illusion of security</a>↩
  461. </div>↩
  462. </div>↩
  463. </div>↩
  464. <div class="col-12 col-md-3">↩
  465. <a href="/cybersecurity/yubikey/" class="btn btn-block btn-info">↩
  466. <strong>YubiKey Authentication</strong></a>↩
  467. </div>↩
  468. <div class="col-12 col-md-3">↩
  469. <a href="/cybersecurity/yubikey/pam_pkcs11.html" class="btn btn-block btn-info">↩
  470. <strong>YubiKey Authentication With pam_pkcs11.so</strong></a>↩
  471. </div>↩
  472. <div class="col-12 col-md-3">↩
  473. <a href="/cybersecurity/yubikey/pam_yubico.html" class="btn btn-block btn-info">↩
  474. <strong>YubiKey Authentication With pam_yubico.so</strong></a>↩
  475. </div>↩
  476. <div class="col-12 col-md-3">↩
  477. <a href="/cybersecurity/yubikey/pam_u2f.html" class="btn btn-block btn-info">↩
  478. <strong>YubiKey Authentication With pam_u2f.so</strong></a>↩
  479. </div>↩
  480. <div class="col-12 col-md-6">↩
  481. <a href="/open-source/linux-pam-compliance/" class="btn btn-block btn-info">↩
  482. <strong>Linux PAM Configuration for Compliance</strong><br>↩
  483. <em> Configure PAM to meet US DoD/DISA↩
  484. STIG Compliance Requirements</em></a>↩
  485. </div>↩
  486. <div class="col-12 col-md-6">↩
  487. <a href="/cybersecurity/hacker-passwords.html" class="btn btn-block btn-info">↩
  488. <strong>Reverse-Engineering the Hacker</strong><br>↩
  489. <em> What types of passwords will a typical↩
  490. hacker guess?</em></a>↩
  491. </div>↩
  492. <div class="col-12">↩
  493. <a href="/cybersecurity/authentication.html" class="btn btn-block btn-info">↩
  494. <strong>Authentication Tools</strong><br>↩
  495. <em>Windows authentication details,↩
  496. Well-known default passwords,↩
  497. Studies of real-world passwords↩
  498. and PINs,↩
  499. Kerberos,↩
  500. Password tools,↩
  501. Active Authentication,↩
  502. sudo,↩
  503. Tokens, Biometrics</em></a>↩
  504. </div>↩
  505. </div>↩
  506. ↩
  507. <p class="canvased textright" style="margin-top:5px;">↩
  508. <strong><em>He that breaks a thing to find out what it is has left the path of wisdom.</em></strong>↩
  509. <br>&mdash; Gandalf in <em>The Fellowship of the Ring</em>↩
  510. </p>↩
  511. ↩
  512. <h2 class="centered"> System Security (operating system auditing↩
  513. and hardening)</h2>↩
  514. ↩
  515. <div class="row centered">↩
  516. <div class="col-12 col-md-6 col-lg-8">↩
  517. <a href="/cybersecurity/sysaudit.html" class="btn btn-block btn-info">↩
  518. <strong>System Security Auditing and↩
  519. Monitoring Tools</strong><br>↩
  520. <em>Common Criteria,↩
  521. US DOD STIGs and SRRs,↩
  522. SCAP tools,↩
  523. US Federal Desktop Core Configuration,↩
  524. printer security,↩
  525. Windows Security Configuration and↩
  526. Analysis Snap-In,↩
  527. Lynis Enterprise Suite,↩
  528. older tools (TARA, COPS, Titan,↩
  529. Bastille)</em></a>↩
  530. </div>↩
  531. <div class="col-12 col-md-3 col-lg-2">↩
  532. <a href="/cybersecurity/openscap.html" class="btn btn-block btn-info">↩
  533. <strong>System Auditing and Hardening with OpenSCAP</strong></a>↩
  534. </div>↩
  535. <div class="col-12 col-md-3 col-lg-2">↩
  536. <a href="/cybersecurity/hardware.html" class="btn btn-block btn-info">↩
  537. <strong>Hardware&nbsp;/ Firmware Exploits</strong></a>↩
  538. </div>↩
  539. </div>↩
  540. <div class="row centered">↩
  541. <div class="col-12 col-md-3 col-lg-2">↩
  542. <a href="/cybersecurity/physical.html" class="btn btn-block btn-info">↩
  543. <strong>Physical Security</strong></a>↩
  544. </div>↩
  545. <div class="col-12 col-md-9 col-lg-10">↩
  546. <a href="/cybersecurity/os-specific.html" class="btn btn-block btn-info">↩
  547. <strong>OS-Specific Security Issues</strong><br>↩
  548. <em>Cisco IOS, Linux, Solaris,↩
  549. Tru64 (ULTRIX, OSF/1),↩
  550. IRIX, AIX, DOS, Macintosh,↩
  551. Novell, AS/400, VMS, Windows</em></a>↩
  552. </div>↩
  553. </div>↩
  554. <div class="row centered">↩
  555. <div class="col-12 col-md-5">↩
  556. <a href="/cybersecurity/virtualization.html" class="btn btn-block btn-info">↩
  557. <strong>Attacks on Virtualization Security </strong></a>↩
  558. </div>↩
  559. <div class="col-12 col-md-7">↩
  560. <a href="/cybersecurity/root-password.html" class="btn btn-block btn-info">↩
  561. <strong>How to harden a default Linux or BSD installation</strong></a>↩
  562. </div>↩
  563. </div>↩
  564. <div class="row centered">↩
  565. <div class="col-12">↩
  566. <a href="/cybersecurity/selinux/" class="btn btn-block btn-info">↩
  567. <strong>Security-Enhanced Linux</strong><br>↩
  568. <em>How to use SELinux booleans and↩
  569. build and use custom SELinux policy modules</em></a>↩
  570. </div>↩
  571. </div>↩
  572. <div class="row centered">↩
  573. <div class="col-12 col-md-4">↩
  574. <a href="/cybersecurity/intrusion.html" class="btn btn-block btn-info">↩
  575. <strong>Intrusion Detection Tools</strong><br>↩
  576. <em>Tripwire, AIDE, Snort,↩
  577. RazorBack, ACID-XML, SNARE, BackLog,↩
  578. NetRanger, NetStalker, GrIDS</em></a>↩
  579. </div>↩
  580. <div class="col-12 col-md-3">↩
  581. <a href="/cybersecurity/intrusion-intro/" class="btn btn-block btn-info">↩
  582. <strong>Intrusion Detection Introduction</strong><br>↩
  583. A small example</a>↩
  584. </div>↩
  585. <div class="col-12 col-md-3">↩
  586. <a href="/cybersecurity/intrusion-analysis/" class="btn btn-block btn-info">↩
  587. <strong>Analyzing multiple intrusions into↩
  588. a poorly configured Linux system</strong></a>↩
  589. </div>↩
  590. <div class="col-12 col-md-2">↩
  591. <a href="/open-source/stig-compliance.html" class="btn btn-block btn-info">↩
  592. <strong>US DOD/DISA STIG Compliance for Linux</strong></a>↩
  593. </div>↩
  594. </div>↩
  595. ↩
  596. <p class="canvased textright" style="margin-top:5px;">↩
  597. <strong><em>From a practical standpoint the security problem will↩
  598. remain as long as manufacturers remain↩
  599. committed to current system architectures,↩
  600. produced without a firm requirement for↩
  601. security.↩
  602. As long as there is support for ad hoc fixes↩
  603. and security packages for these inadequate↩
  604. designs and as long as the illusory results↩
  605. of penetration teams are accepted as↩
  606. demonstrations of a computer system security,↩
  607. proper security will not be a reality.</em></strong>↩
  608. <br>&mdash; Roger Schell in the USAF report↩
  609. <em>Preliminary Notes on the Design of Secure Military↩
  610. Computer Systems,</em> written in 1973↩
  611. </p>↩
  612. ↩
  613. <h2 class="centered">Public-Key Infrastructure, TLS, and SSL</h2>↩
  614. ↩
  615. <div class="row centered">↩
  616. <div class="col-7 col-md-5">↩
  617. <a href="/cybersecurity/how-browsers-use-https.html" class="btn btn-block btn-info">↩
  618. <strong>How Browsers Use HTTPS and TLS to Secure Web Traffic</strong></a>↩
  619. </div>↩
  620. <div class="col-5 col-md-2">↩
  621. <a href="/cybersecurity/ssl-tls.html" class="btn btn-block btn-info">↩
  622. <strong>SSL/TLS Security</strong></a>↩
  623. </div>↩
  624. <div class="col-12 col-md-5">↩
  625. <a href="/cybersecurity/pki-failures.html" class="btn btn-block btn-info">↩
  626. <strong>Failures of the Internet's Public-Key Infrastructure (PKI)</strong></a>↩
  627. </div>↩
  628. </div>↩
  629. <div class="row centered">↩
  630. <div class="col-12 col-md-3">↩
  631. <a href="/open-source/nginx-openssl-quantum-safe/" class="btn btn-info btn-block">↩
  632. <strong>Nginx, OpenSSL, and Open Quantum Safe</strong></a>↩
  633. </div>↩
  634. <div class="col-6 col-md-4">↩
  635. <a href="/open-source/google-freebsd-tls/" class="btn btn-info btn-block">↩
  636. <strong>How to Use a Let's Encrypt TLS Certificate on Google Cloud</strong></a>↩
  637. </div>↩
  638. <div class="col-6 col-md-5">↩
  639. <a href="/open-source/letsencrypt-tls-cert-godaddy.html" class="btn btn-info btn-block">↩
  640. <strong>How to Use a Let's Encrypt TLS Certificate on GoDaddy Shared Hosting</strong></a>↩
  641. </div>↩
  642. </div>↩
  643. ↩
  644. <p class="canvased textright" style="margin-top:5px;">↩
  645. <strong><em>He who fights monsters should see to it that↩
  646. he himself does not become a monster.↩
  647. And if you gaze long enough into an abyss,↩
  648. the abyss will also gaze into you.</em></strong>↩
  649. <br>&mdash; Friedrich Nietzsche in↩
  650. <a href="https://amzn.to/44yBmeC">↩
  651. <em>Beyond Good and Evil</em></a>↩
  652. </p>↩
  653. ↩
  654. <h2 class="centered">Network Security</h2>↩
  655. ↩
  656. <div class="row centered">↩
  657. <div class="col-12 col-lg-8">↩
  658. <a href="/cybersecurity/monitoring.html" class="btn btn-block btn-info">↩
  659. <strong>Network Monitoring / Protocol Analysis /↩
  660. Packet Sniffing Tools</strong><br>↩
  661. <em>Linux-based, Windows-based,↩
  662. switch spoofing,↩
  663. Wireless LAN/WAN security,↩
  664. WLAN antenna construction,↩
  665. packet-sniffing attack detection</em></a>↩
  666. </div>↩
  667. <div class="col-12 col-md-6 col-lg-4">↩
  668. <a href="/cybersecurity/router-update.html" class="btn btn-block btn-info">↩
  669. <strong>Update Your Router</strong><br>↩
  670. Stay Secure at Home</a>↩
  671. </div>↩
  672. <div class="col-12 col-md-6 col-lg-4">↩
  673. <a href="/cybersecurity/telecom-outages.html" class="btn btn-block btn-info">↩
  674. <strong>Telecommunications Outages</strong><br>↩
  675. <em>Submarine cables, satellites</em></a>↩
  676. </div>↩
  677. <div class="col-6 col-md-6 col-lg-4">↩
  678. <a href="/open-source/openbsd-wireless-wpa2.html" class="btn btn-block btn-info">↩
  679. <strong>802.11i / WPA2</strong><br>↩
  680. <em>Wireless networking</em></a>↩
  681. </div>↩
  682. <div class="col-6 col-md-6 col-lg-4">↩
  683. <a href="/cybersecurity/availability/ddos.html" class="btn btn-block btn-info">↩
  684. <strong>DDoS</strong> <br>↩
  685. <em>Distributed Denial of Service</em></a>↩
  686. </div>↩
  687. </div>↩
  688. <div class="row centered">↩
  689. <div class="col-6">↩
  690. <a href="/cybersecurity/bgp-hijacking.html" class="btn btn-block btn-info">↩
  691. <strong>BGP Hijacking</strong><br>↩
  692. <em>Plus outages caused by politics and errors</em></a>↩
  693. </div>↩
  694. <div class="col-6">↩
  695. <a href="/cybersecurity/comsec.html" class="btn btn-block btn-info">↩
  696. <strong>COMSEC</strong><br>↩
  697. <em>Attacking Mobile&nbsp;/ Cellular&nbsp;/ GSM Telephony</em></a>↩
  698. </div>↩
  699. <div class="col-12">↩
  700. <a href="/cybersecurity/netaudit.html" class="btn btn-block btn-info">↩
  701. <strong>Network Security Auditing Tools</strong><br>↩
  702. <em>Top 100 Network Security Tools,↩
  703. Lists of TCP ports used by attacks,↩
  704. Port scanners,↩
  705. Network vulnerability testing,↩
  706. Automatic Teller Machine↩
  707. (ATM) security</em></a>↩
  708. </div>↩
  709. <div class="col-5 col-xl-2">↩
  710. <a href="/cybersecurity/www.html" class="btn btn-block btn-info">↩
  711. <strong>Web Security</strong></a>↩
  712. </div>↩
  713. <div class="col-7 col-xl-3">↩
  714. <a href="/cybersecurity/stack-hardening.html" class="btn btn-block btn-info">↩
  715. <strong>TCP/IP Stack hardening</strong></a>↩
  716. </div>↩
  717. <div class="col-7 col-xl-4">↩
  718. <a href="/cybersecurity/qr-nfc.html" class="btn btn-block btn-info">↩
  719. <strong>QR codes and Near-Field Communication Risks</strong></a>↩
  720. </div>↩
  721. <div class="col-5 col-xl-3">↩
  722. <a href="/open-source/ssh.html" class="btn btn-block btn-info">↩
  723. <strong>How to set up and use SSH</strong></a>↩
  724. </div>↩
  725. </div>↩
  726. <div class="row centered">↩
  727. <div class="col-12 col-md-6">↩
  728. <a href="/cybersecurity/firewall.html" class="btn btn-block btn-info">↩
  729. <strong>Firewall Tools</strong><br>↩
  730. <em>Linux/Unix-based, Windows based,↩
  731. SOHO firewalls, Commercial vendors</em></a>↩
  732. </div>↩
  733. <div class="col-12 col-md-6">↩
  734. <a href="/cybersecurity/attack-study/" class="btn btn-block btn-info">↩
  735. <strong>Network Attack Analysis</strong><br>↩
  736. <em>Classifying and Identifying Attack Patterns↩
  737. With Textual Analysis Tools</em></a>↩
  738. </div>↩
  739. </div>↩
  740. ↩
  741. <p class="canvased textright" style="margin-top:5px;">↩
  742. <strong><em>The world is never going to be perfect, either on-↩
  743. or offline; so let's not set impossibly↩
  744. high standards for online.</em></strong>↩
  745. <br>&mdash; Esther Dyson↩
  746. </p>↩
  747. ↩
  748. <h2 class="centered"> Cloud Security </h2>↩
  749. ↩
  750. <div class="row centered">↩
  751. <div class="col-12 col-md-8">↩
  752. <a href="/cybersecurity/isc2-ccsp/" class="btn btn-block btn-info">↩
  753. <strong>Study guide for the (ISC)<sup>2</sup>↩
  754. CCSP (Certified Cloud Security↩
  755. Professional) Exam</strong></a>↩
  756. </div>↩
  757. <div class="col-12 col-md-4">↩
  758. <a href="/cybersecurity/cloud.html" class="btn btn-block btn-info">↩
  759. <strong>An Overview of Cloud Security</strong> </a>↩
  760. </div>↩
  761. </div>↩
  762. <div class="row centered">↩
  763. <div class="col-12 col-md-4">↩
  764. <a href="/cybersecurity/availability/cloud-archiving.html" class="btn btn-block btn-info">↩
  765. <strong>Cloud Archiving</strong><br>↩
  766. <em>Google Coldline, AWS Glacier,↩
  767. Cloud archiving tools</em></a>↩
  768. </div>↩
  769. <div class="col-12 col-md-4">↩
  770. <a href="/cybersecurity/cloud-survey.html" class="btn btn-block btn-info">↩
  771. <strong>Security Concerns of Cloud Technology Users:↩
  772. A Survey of Major Cloud Customers </strong> </a>↩
  773. </div>↩
  774. <div class="col-12 col-md-4">↩
  775. <a href="/open-source/linux-blog.html" class="btn btn-block btn-info">↩
  776. <strong>Linux and Security Blog &mdash;↩
  777. Thoughts from Time to Time on↩
  778. Linux, Security, and the Cloud</strong></a>↩
  779. </div>↩
  780. </div>↩
  781. <div class="row centered">↩
  782. <div class="col-12 col-lg-4">↩
  783. <a href="/cybersecurity/rsyslog-tls/" class="btn btn-block btn-info">↩
  784. <strong>Secure Logging with Rsyslog and TLS</strong></a>↩
  785. </div>↩
  786. <div class="col-12 col-md-6 col-lg-4">↩
  787. <a href="/cybersecurity/ec2-secure-storage.html" class="btn btn-block btn-info">↩
  788. <strong>How to set up encrypted storage on Amazon EC2</strong></a>↩
  789. </div>↩
  790. <div class="col-12 col-md-6 col-lg-4">↩
  791. <a href="/cybersecurity/cloud-exploit.html" class="btn btn-block btn-info">↩
  792. <strong>Hacked in the Cloud &mdash; An Attacker Takes Over a Cloud Server </strong></a>↩
  793. </div>↩
  794. </div>↩
  795. ↩
  796. <div class="row centered">↩
  797. ↩
  798. <div class="col-12 col-md-6 textleft">↩
  799. ↩
  800. <h2 class="centered"> Malware, Social Engineering, and Software Security </h2>↩
  801. ↩
  802. <p>↩
  803. <strong>Good free anti-virus / anti-malware software</strong>↩
  804. includes the following.↩
  805. ZoneAlarm incorporates spyware detection and↩
  806. removal software.↩
  807. <br>↩
  808. <a href="https://www.clamav.net/" class="btn btn-danger">↩
  809. ClamAV</a>↩
  810. &nbsp;↩
  811. <a href="https://www.clamxav.com/" class="btn btn-danger">↩
  812. ClamXav</a>↩
  813. &nbsp;↩
  814. <a href="https://www.avira.com/" class="btn btn-danger">Avira</a>↩
  815. &nbsp;↩
  816. <a href="https://www.avg.com/free-antivirus-download" class="btn btn-danger">AVG</a>↩
  817. &nbsp;↩
  818. <a href="https://www.zonealarm.com/" class="btn btn-danger">ZoneAlarm</a>↩
  819. </p>↩
  820. ↩
  821. <p>↩
  822. I <em class="underlined">used to</em> recommend↩
  823. <a href="https://www.avast.com/" class="btn btn-danger">Avast!</a>,↩
  824. but then it was↩
  825. <a href="https://www.msn.com/en-us/news/technology/avast-fined-165-million-for-privacy-software-that-actually-sold-users-browsing-data/ar-BB1iJpg2">↩
  826. fined US$&nbsp;16.5 million for↩
  827. selling users' browsing data</a>.↩
  828. </p>↩
  829. ↩
  830. <p>↩
  831. <a href="https://www.virustotal.com/gui/home/upload">↩
  832. <strong>VirusTotal</strong></a>↩
  833. lets you up upload suspicious data for scanning and↩
  834. analysis by several malware detection systems.↩
  835. <br>↩
  836. <a href="https://www.virustotal.com/gui/home/upload" class="btn btn-danger">VirusTotal</a>↩
  837. </p>↩
  838. ↩
  839. <p>↩
  840. The↩
  841. <strong><a href="https://support.kaspersky.com/viruses/rescuedisk">↩
  842. Kaspersky Rescue Disk</a></strong>↩
  843. lets you safely boot and clean infected Windows↩
  844. systems that can't be cleaned with the normal tools.↩
  845. </p>↩
  846. <p>↩
  847. <a href="https://malware.lu/">Malware.lu</a>↩
  848. is a repository of malware and technical analyses for↩
  849. security researchers.↩
  850. </p>↩
  851. <p>↩
  852. Attrition.org has a↩
  853. <a href="https://attrition.org/errata/cpo/">↩
  854. list of vendors that have shipped malware↩
  855. with their products</a>.↩
  856. </p>↩
  857. ↩
  858. </div>↩
  859. ↩
  860. <div class="col-12 col-md-6">↩
  861. <div class="centered cb">↩
  862. <ins class="adsbygoogle responsive"↩
  863. style="display:block;"↩
  864. data-full-width-responsive="true"↩
  865. data-ad-client="ca-pub-5845932372655417"↩
  866. data-ad-slot="4849215406"></ins>↩
  867. <script>↩
  868. (adsbygoogle = window.adsbygoogle || []).push({});↩
  869. </script>↩
  870. </div>↩
  871. </div>↩
  872. ↩
  873. </div>↩
  874. ↩
  875. <div class="row centered">↩
  876. <div class="col-12 col-md-4 col-lg-3">↩
  877. <a href="/cybersecurity/scams-spam-phishing.html" class="btn btn-block btn-info">↩
  878. <strong>Learn about scams, spam, phishing, and worse,↩
  879. and take some great Phishing IQ tests</strong></a>↩
  880. </div>↩
  881. <div class="col-12 col-md-8 col-lg-4">↩
  882. <a href="/cybersecurity/hostile/" class="btn btn-block btn-info">↩
  883. <strong>Analyzing Hostile Data</strong><br>↩
  884. <em>An overview of viruses, worms, trojans,↩
  885. downloaders and other malware, plus↩
  886. analysis of: Bagel, Mytob, Mydoom,↩
  887. and more</em></a>↩
  888. </div>↩
  889. <div class="col-12 col-lg-5">↩
  890. <a href="/cybersecurity/software.html" class="btn btn-block btn-info">↩
  891. <strong>Software Security Tools</strong><br>↩
  892. <em>How to develop software that is more secure,↩
  893. The SAFECode <em>Fundamental Practices for Secure Software Development,</em>↩
  894. C/C++ Security,↩
  895. Python Security,↩
  896. Java Security,↩
  897. Node.js Security,↩
  898. ActiveX Attacks,↩
  899. Writing Exploit Code</em></a>↩
  900. </div>↩
  901. <div class="col-12">↩
  902. <a href="/cybersecurity/extortion.html" class="btn btn-block btn-info">↩
  903. <strong>Analyzing a System Hacked by Extortionware, also called Police Ransomware</strong></a>↩
  904. </div>↩
  905. <div class="col-12 col-md-6 col-lg-3">↩
  906. <a href="/cybersecurity/hoax.html" class="btn btn-block btn-info">↩
  907. <strong>Social Engineering and Fighting Internet Hoaxes</strong></a>↩
  908. </div>↩
  909. <div class="col-12 col-md-6 col-lg-3">↩
  910. <a href="/cybersecurity/html-email.html" class="btn btn-block btn-info">↩
  911. <strong>Why HTML E-mail is Dangerous</strong></a>↩
  912. </div>↩
  913. <div class="col-12 col-md-6 col-lg-3">↩
  914. <a href="/cybersecurity/web-mail-spear-phishing.html" class="btn btn-block btn-info">↩
  915. <strong>Analyzing Web Mail Abuse and Spear-Phishing</strong></a>↩
  916. </div>↩
  917. <div class="col-12 col-md-6 col-lg-3">↩
  918. <a href="/cybersecurity/scam-analysis.html" class="btn btn-block btn-info">↩
  919. <strong>Analyzing a Phishing Scam Attempt</strong></a>↩
  920. </div>↩
  921. </div>↩
  922. ↩
  923. <p class="canvased textright" style="margin-top:5px;">↩
  924. <strong><em>We kill people based on metadata.</em></strong>↩
  925. <br>&mdash; Former NSA and CIA director Michael Hayden, 2014↩
  926. </p>↩
  927. ↩
  928. <h2 class="centered">Reference Material</h2>↩
  929. ↩
  930. <div class="row centered">↩
  931. <div class="col-12 col-md-6">↩
  932. <a href="/cybersecurity/exam-prep.html" class="btn btn-block btn-info">↩
  933. <strong>How to Prepare For, and Pass,↩
  934. Certification Exams</strong></a>↩
  935. </div>↩
  936. <div class="col-12 col-md-6">↩
  937. <a href="/cybersecurity/comptia/" class="btn btn-block btn-info">↩
  938. <strong>Guidance for passing the CompTIA↩
  939. Security+ Certification Exam</strong></a>↩
  940. </div>↩
  941. </div>↩
  942. <div class="row centered">↩
  943. <div class="col-12 col-md-6">↩
  944. <a href="/cybersecurity/isc2-cissp/" class="btn btn-block btn-info">↩
  945. <strong>Study guide for the (ISC)<sup>2</sup>↩
  946. CISSP (Certified Information Systems↩
  947. Security Professional) Exam</strong></a>↩
  948. </div>↩
  949. <div class="col-12 col-md-6">↩
  950. <a href="/cybersecurity/isc2-ccsp/" class="btn btn-block btn-info">↩
  951. <strong>Study guide for the (ISC)<sup>2</sup>↩
  952. CCSP (Certified Cloud Security↩
  953. Professional) Exam</strong></a>↩
  954. </div>↩
  955. </div>↩
  956. <div class="row centered">↩
  957. <div class="col-12 col-md-6">↩
  958. <a href="/cybersecurity/bulletins.html" class="btn btn-block btn-info">↩
  959. <strong>Infosec Bulletins and Mailing Lists</strong></a>↩
  960. </div>↩
  961. <div class="col-12 col-md-6">↩
  962. <a href="/cybersecurity/policy.html" class="btn btn-block btn-info">↩
  963. <strong>Policy Requirements and Guidance</strong></a>↩
  964. </div>↩
  965. </div>↩
  966. ↩
  967. <p>↩
  968. Here is a chart comparing certifications,↩
  969. someone picked this up at a SANS event.↩
  970. An interactive updated version is↩
  971. <a href="https://pauljerimy.com/security-certification-roadmap/">↩
  972. here</a>.↩
  973. </p>↩
  974. ↩
  975. <div class="centered">↩
  976. <img src="pictures/cert_2020.jpg"↩
  977. alt="Chart of certifications as of 2020."↩
  978. class="bordered" loading="lazy">↩
  979. </div>↩
  980. ↩
  981. <div class="row centered">↩
  982. <div class="col-12">↩
  983. <a href="/cybersecurity/rfcs.html" class="btn btn-block btn-info">↩
  984. <strong>Security-Related RFCs (Valuable Documents!)↩
  985. and Mitre nomenclature projects</strong><br>↩
  986. <em>Some of these function as dictionaries↩
  987. and explain the terminology.↩
  988. Others provide the formal definitions↩
  989. of networking protocols</em></a>↩
  990. </div>↩
  991. <div class="col-12 col-md-2">↩
  992. <a href="/cybersecurity/major-breaches.html" class="btn btn-block btn-info">↩
  993. <strong>Major Breaches</strong><br>↩
  994. <em>Password dumps, large data breaches</em></a>↩
  995. </div>↩
  996. <div class="col-12 col-md-4">↩
  997. <a href="/cybersecurity/generalinfo.html" class="btn btn-block btn-info">↩
  998. <strong>General Information</strong><br>↩
  999. <em>DNS Security Issues,↩
  1000. Incidents and Anecdotes,↩
  1001. Government Warnings and Reactions</em></a>↩
  1002. </div>↩
  1003. <div class="col-12 col-md-6">↩
  1004. <a href="/cybersecurity/cyberwar/" class="btn btn-block btn-info">↩
  1005. <strong>Cyberwar, Economic Espionage, and Advanced Persistent Threats</strong><br>↩
  1006. <em>Military Applications of Network↩
  1007. Attack and Defense,↩
  1008. International Conflict on the Internet,↩
  1009. Military-Industrial Espionage,↩
  1010. Viruses and Hacking,↩
  1011. Threat Reports and Warnings,↩
  1012. Offensive Information Warfare &amp;↩
  1013. Information Operations</em></a>↩
  1014. </div>↩
  1015. </div>↩
  1016. <div class="row centered">↩
  1017. <div class="col-12 col-md-7 col-lg-9">↩
  1018. <a href="/cybersecurity/infosec-response.html" class="btn btn-block btn-info">↩
  1019. <strong>Infosec Response Teams</strong><br>↩
  1020. <em>Incident Response Teams,↩
  1021. Assistance and Guidance,↩
  1022. Research and Development, Vendors,↩
  1023. Risk Management and Insurance↩
  1024. Coverage</em></a>↩
  1025. </div>↩
  1026. <div class="col-12 col-md-5 col-lg-3">↩
  1027. <a href="/cybersecurity/badguys.html" class="btn btn-block btn-info">↩
  1028. <strong>Keeping Track of the Bad Guys</strong><br>↩
  1029. <em>Classic Hackers, Hacker Technology</em></a>↩
  1030. </div>↩
  1031. </div>↩
  1032. <div class="row centered">↩
  1033. <div class="col-12 col-md-6 col-lg-4">↩
  1034. <a href="/cybersecurity/history/" class="btn btn-block btn-info">↩
  1035. <strong>Cryptographic History</strong></a>↩
  1036. </div>↩
  1037. <div class="col-12 col-md-6 col-lg-4">↩
  1038. <a href="/open-source/crashdumps.html" class="btn btn-block btn-info">↩
  1039. <strong>The Gallery of Crash Dump Screens</strong></a>↩
  1040. </div>↩
  1041. <div class="col-12 col-md-6 col-lg-4">↩
  1042. <a href="/cybersecurity/crypto/haiku.html" class="btn btn-block btn-info">↩
  1043. <strong>Cryptographic Haiku</strong></a>↩
  1044. </div>↩
  1045. </div>↩
  1046. ↩
  1047. <p>↩
  1048. <a href="https://www.cvedetails.com/"><strong>CVE Details</strong></a>↩
  1049. is a great source of information on vulnerabilities.↩
  1050. You can search by CVE reference, by vendor, and product name.↩
  1051. </p>↩
  1052. ↩
  1053. </nav>↩
  1054. ↩
  1055. <h2> Internet threat warnings </h2>↩
  1056. ↩
  1057. <p>↩
  1058. I find these to be helpful sources of information on↩
  1059. current events and trends:↩
  1060. </p>↩
  1061. <p>↩
  1062. <a href="https://krebsonsecurity.com/" class="btn btn-success" style="margin:5px;">↩
  1063. Krebs On Security</a>↩
  1064. <a href="https://securelist.com/" class="btn btn-success" style="margin:5px;">↩
  1065. SecureList</a>↩
  1066. <a href="https://www.us-cert.gov/ncas/current-activity" class="btn btn-success" style="margin:5px;">↩
  1067. US-CERT Current Activity</a>↩
  1068. <a href="https://www.flashpoint.io/blog/" class="btn btn-success" style="margin:5px;">↩
  1069. Flashpoint Intelligence Corner</a>↩
  1070. </p>↩
  1071. ↩
  1072. <div class="centered">↩
  1073. <img src="https://www.dshield.org/images/dshield_live_banner.png"↩
  1074. alt="DShield live banner."↩
  1075. loading="lazy">↩
  1076. </div>↩
  1077. ↩
  1078. <h2> Internet security "global dashboards" </h2>↩
  1079. ↩
  1080. <p>↩
  1081. Some of these are useful, some have a relatively high↩
  1082. level of hype, but you might find some of these useful:↩
  1083. </p>↩
  1084. ↩
  1085. <p>↩
  1086. <a href="https://map.internetintel.oracle.com/" class="btn btn-warning" style="margin:5px;">↩
  1087. Oracle Internet Intelligence</a>↩
  1088. <a href="https://cybermap.kaspersky.com/" class="btn btn-warning" style="margin:5px;">↩
  1089. Kaspersky</a>↩
  1090. <a href="https://dshield.org/" class="btn btn-warning" style="margin:5px;">↩
  1091. DShield</a>↩
  1092. <a href="http://www.internettrafficreport.com/" class="btn btn-warning" style="margin:5px;">↩
  1093. Internet Traffic Report</a>↩
  1094. <a href="https://isc.sans.org/" class="btn btn-warning" style="margin:5px;">↩
  1095. SANS Internet Storm Center</a>↩
  1096. <a href="https://www.digitalattackmap.com/#anim=1&amp;color=0&amp;country=ALL&amp;list=0&amp;time=16434&amp;view=map" class="btn btn-warning" style="margin:5px;">↩
  1097. Live Digital Attack Map</a>↩
  1098. <a href="https://radar.securitywizardry.com/" class="btn btn-warning" style="margin:5px;">↩
  1099. Security Wizardry Computer Network <br>↩
  1100. Defence Situational Awareness</a>↩
  1101. </p>↩
  1102. ↩
  1103. <h2> Where to go from here </h2>↩
  1104. ↩
  1105. <p>↩
  1106. Make sure you understand your systems well, and set them↩
  1107. up properly!↩
  1108. As Hippocrates said, <em>"Primum non nocere"</em>, or↩
  1109. <em>"First, do no harm."</em>↩
  1110. </p>↩
  1111. ↩
  1112. <p>↩
  1113. Be aware that your browser always gives away some information↩
  1114. about you, unless you are using↩
  1115. <a href="https://www.torproject.org/">↩
  1116. Tor</a>↩
  1117. and using it very carefully.↩
  1118. Your browser just provided this information:↩
  1119. </p>↩
  1120. ↩
  1121. <table class="bordered" style="font-size: 80%; max-width:100%; display:inline-block; white-space:nowrap;">↩
  1122. <tr><td>REMOTE ADDR</td><td>23.22.170.185</td></tr>↩
  1123. <tr><td>REMOTE PORT</td><td>54258</td></tr>↩
  1124. <tr><td>HTTP CONNECTION</td><td>Keep-Alive</td></tr>↩
  1125. <tr><td>HTTP HOST</td><td>cromwell-intl.com</td></tr>↩
  1126. <tr><td>HTTP ACCEPT ENCODING</td><td>gzip</td></tr>↩
  1127. <tr><td>HTTP ACCEPT</td><td>text/html, application/xhtml+xml, application/xml; q=0.9, */*; q=0.8</td></tr>↩
  1128. <tr><td>HTTP USER AGENT</td><td>Validator.nu/LV https://validator.w3.org/services</td></tr>↩
  1129. </table>↩
  1130. ↩
  1131. <!-- start of footer.html -->↩
  1132. <footer>↩
  1133. <nav class="cb centered">↩
  1134. <hr style="margin-bottom: 2px; padding-bottom: 0px;">↩
  1135. ↩
  1136. <!-- Amazon oneTag script -->↩
  1137. <div id="amzn-assoc-ad-06659344-4b29-4e93-b5fa-6c771be869c0"></div>↩
  1138. <script async src="https://z-na.associates-amazon.com/onetag/v2?MarketPlace=US&instanceId=06659344-4b29-4e93-b5fa-6c771be869c0"></script>↩
  1139. ↩
  1140. <!-- Google matched content -->↩
  1141. <p style="font-size:0.8rem; text-align:left; margin:0; padding:2px;">↩
  1142. Now some lurid advertisements from Google AdSense:↩
  1143. </p>↩
  1144. <div class="centered">↩
  1145. <ins class="adsbygoogle"↩
  1146. style="display:block;"↩
  1147. data-full-width-responsive="true"↩
  1148. data-ad-client="ca-pub-5845932372655417"↩
  1149. data-ad-slot="9123376601"↩
  1150. data-ad-format="autorelaxed"></ins>↩
  1151. <script>↩
  1152. (adsbygoogle = window.adsbygoogle || []).push({});↩
  1153. </script>↩
  1154. </div>↩
  1155. ↩
  1156. <nav class="row centered" style="margin-top:1px; padding-top:0; margin-bottom: 1em;">↩
  1157. <div class="col-6 col-md-3">↩
  1158. <a href="/" class="btn btn-info btn-block">↩
  1159. Home</a>↩
  1160. </div>↩
  1161. <div class="col-6 col-md-3">↩
  1162. <a href="/travel/" class="btn btn-info btn-block">↩
  1163. Travel</a>↩
  1164. </div>↩
  1165. <div class="col-6 col-md-3">↩
  1166. <a href="/open-source/" class="btn btn-info btn-block">↩
  1167. Linux/Unix</a>↩
  1168. </div>↩
  1169. <div class="col-6 col-md-3">↩
  1170. <a href="/cybersecurity/" class="btn btn-info btn-block">↩
  1171. Cybersecurity</a>↩
  1172. </div>↩
  1173. <div class="col-6 col-md-3">↩
  1174. <a href="/networking/" class="btn btn-info btn-block">↩
  1175. Networking</a>↩
  1176. </div>↩
  1177. <div class="col-6 col-md-3">↩
  1178. <a href="/technical/" class="btn btn-info btn-block">↩
  1179. Technical</a>↩
  1180. </div>↩
  1181. <div class="col-6 col-md-3">↩
  1182. <a href="/radio/" class="btn btn-info btn-block">↩
  1183. Radio</a>↩
  1184. </div>↩
  1185. <div class="col-6 col-md-3">↩
  1186. <a href="/blog/" class="btn btn-info btn-block">↩
  1187. Blog</a>↩
  1188. </div>↩
  1189. </nav>↩
  1190. ↩
  1191. <div class="row centered">↩
  1192. ↩
  1193. <div class="col-4 col-lg-2">↩
  1194. <a href="https://www.freebsd.org/">↩
  1195. <img src="/ssi/powerlogo.gif" alt="FreeBSD" loading="lazy"></a>↩
  1196. </div>↩
  1197. ↩
  1198. <div class="col-4 col-lg-2">↩
  1199. <a href="https://nginx.org/">↩
  1200. <img src="/ssi/nginx_logo-70pc.png" alt="Nginx" loading="lazy"></a>↩
  1201. </div>↩
  1202. ↩
  1203. <div class="col-4 col-lg-2">↩
  1204. <a href="https://www.unicode.org/">↩
  1205. <img src="/ssi/unicode.png"↩
  1206. alt="Valid Unicode."↩
  1207. loading="lazy"↩
  1208. style="padding: 0 0 8px 0; margin: 0;"></a>↩
  1209. </div>↩
  1210. ↩
  1211. <div class="col-4 col-lg-2">↩
  1212. <a href="https://notbyai.fyi/">↩
  1213. <img src="/ssi/produced-by-human.png"↩
  1214. alt="Produced by a human, not A.I."↩
  1215. loading="lazy"></a>↩
  1216. </div>↩
  1217. ↩
  1218. <div class="col-4 col-lg-2">↩
  1219. <a href="https://validator.w3.org/nu/?showsource=yes&amp;doc=https://cromwell-intl.com/cybersecurity/Index.html"><img src="/ssi/html5-badge-h-css3-semantics.png"↩
  1220. alt="Valid HTML 5. Validate it here."↩
  1221. loading="lazy"↩
  1222. style="padding: 0; margin: 0;"></a>↩
  1223. </div>↩
  1224. ↩
  1225. <div class="col-4 col-lg-2">↩
  1226. <a href="https://jigsaw.w3.org/css-validator/check/referer">↩
  1227. <img src="/ssi/valid-css.png"↩
  1228. alt="Valid CSS. Validate it here."↩
  1229. loading="lazy"↩
  1230. style="padding: 5px 0 3px 0; margin: 0;"></a>↩
  1231. </div>↩
  1232. ↩
  1233. </div>↩
  1234. ↩
  1235. <div class="fl">↩
  1236. ↩
  1237. <a href="https://mastodon.world/@bobthetraveler" rel="me" class="badge badge-pill badge-success" style="margin-bottom:5px;"><span style="font-size:1.25rem;">&#x1f9a3;</span> Bob the Traveler</a>↩
  1238. &nbsp;↩
  1239. <a href="https://mstdn.social/@conansysadmin" rel="me" class="badge badge-pill badge-success" style="margin-bottom:5px;"><span style="font-size:1.25rem;">&#x1f9a3;</span> Conan the Sysadmin</a>↩
  1240. <br>↩
  1241. ↩
  1242. <!--↩
  1243. <a href="https://twitter.com/share" class="twitter-share-button" data-lang="en" data-count="none" style="margin:0; padding:0;">Tweet</a>↩
  1244. <a href="https://twitter.com/ToiletGuru" class="twitter-follow-button" data-show-count="false" data-show-screen-name="false">Follow @ToiletGuru</a>↩
  1245. <br>↩
  1246. ↩
  1247. <a href="https://www.reddit.com/login?dest=https%3A%2F%2Fwww.reddit.com%2Fsubmit" onclick="window.location = 'https://www.reddit.com/login?dest=https%3A%2F%2Fwww.reddit.com%2Fsubmit' + encodeURIComponent(window.location); return false"><img src="https://www.redditstatic.com/spreddit6.gif" alt="submit to reddit" loading="lazy" style="position:relative; margin:0; padding:0;"></a>↩
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  1249. </div>↩
  1250. ↩
  1251. <aside>↩
  1252. <p class="fr textright" style="font-size: 0.8rem;">↩
  1253. Viewport size:↩
  1254. <span id="w"></span> &times; <span id="h"></span>↩
  1255. <script>↩
  1256. (function() {↩
  1257. if (typeof(document.documentElement.clientWidth) != 'undefined') {↩
  1258. var $w = document.getElementById('w'),↩
  1259. $h = document.getElementById('h');↩
  1260. $w.innerHTML = document.documentElement.clientWidth;↩
  1261. $h.innerHTML = document.documentElement.clientHeight;↩
  1262. window.onresize = function(event) {↩
  1263. $w.innerHTML = document.documentElement.clientWidth;↩
  1264. $h.innerHTML = document.documentElement.clientHeight;↩
  1265. };↩
  1266. }↩
  1267. })();↩
  1268. </script>↩
  1269. <br>↩
  1270. <a href="/open-source/google-freebsd-tls/apache-http2-php.html">Protocols</a>: HTTP/1.0 / TLSv1.3<br><a href="/open-source/nginx-openssl-quantum-safe/">Crypto</a>: X25519 / TLS_AES_256_GCM_SHA384</p>↩
  1271. </aside>↩
  1272. ↩
  1273. <!-- margin-bottom needed for infolinks ad -->↩
  1274. <p class="cl centered" style="font-size:0.9rem; margin-bottom:120px;">↩
  1275. &#x00a9; by↩
  1276. <a href="/contact.html">Bob Cromwell</a>↩
  1277. May 2024. Created with↩
  1278. <a href="http://thomer.com/vi/vi.html"><code>vim</code></a>↩
  1279. and↩
  1280. <a href="https://www.imagemagick.org/">ImageMagick</a>,↩
  1281. hosted on↩
  1282. <a href="https://www.freebsd.org/">FreeBSD</a>↩
  1283. with↩
  1284. <a href="https://nginx.org/">Nginx</a>.↩
  1285. <br>↩
  1286. As an Amazon Associate, I earn from qualifying purchases.↩
  1287. <br>↩
  1288. <a href="/contact.html">Contact</a> |↩
  1289. <a href="/cybersecurity/privacy-policy.html">Privacy policy</a> |↩
  1290. <a href="/cybersecurity/root-password.html">Root password here</a>↩
  1291. </p>↩
  1292. ↩
  1293. </nav>↩
  1294. ↩
  1295. ↩
  1296. </footer>↩
  1297. </article>↩
  1298. ↩
  1299. <!-- moved to footer for speed, get JavaScript from CDN -->↩
  1300. <!-- get integrity="..." strings from https://www.srihash.org/ -->↩
  1301. <script async src="https://cdnjs.cloudflare.com/ajax/libs/modernizr/2.8.3/modernizr.min.js" integrity="sha512-3n19xznO0ubPpSwYCRRBgHh63DrV+bdZfHK52b1esvId4GsfwStQNPJFjeQos2h3JwCmZl0/LgLxSKMAI55hgw==" crossorigin="anonymous"></script>↩
  1302. <script async src="https://code.jquery.com/jquery-3.6.1.slim.min.js" integrity="sha384-MYL22lstpGhSa4+udJSGro5I+VfM13fdJfCbAzP9krCEoK5r2EDFdgTg2+DGXdj+" crossorigin="anonymous"></script>↩
  1303. <script async src="https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/js/bootstrap.min.js" integrity="sha384-cVKIPhGWiC2Al4u+LWgxfKTRIcfu0JTxR+EQDz/bgldoEyl4H0zUF0QKbrJ0EcQF" crossorigin="anonymous"></script>↩
  1304. ↩
  1305. <!-- Use this to "lazy-load" images as: <img data-src="...↩
  1306. <script async src="/js/jquery.lazyloadxt.js"></script>↩
  1307. -->↩
  1308. ↩
  1309. <!-- social media button support -->↩
  1310. ↩
  1311. <!-- twitter support -->↩
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  1313. <script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="https://platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs");</script>↩
  1314. -->↩
  1315. ↩
  1316. <!-- facebook support -->↩
  1317. <!--↩
  1318. <div id="fb-root"></div>↩
  1319. <script>(function(d, s, id) {↩
  1320. var js, fjs = d.getElementsByTagName(s)[0];↩
  1321. if (d.getElementById(id)) return;↩
  1322. js = d.createElement(s); js.id = id;↩
  1323. js.src = "https://connect.facebook.net/en_US/all.js#xfbml=1";↩
  1324. fjs.parentNode.insertBefore(js, fjs);↩
  1325. }(document, 'script', 'facebook-jssdk'));</script>↩
  1326. -->↩
  1327. ↩
  1328. <!-- pinterest -->↩
  1329. <!--↩
  1330. <script>↩
  1331. (function(d){↩
  1332. var f = d.getElementsByTagName('SCRIPT')[0], p = d.createElement('SCRIPT');↩
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  1334. p.async = true;↩
  1335. p.src = '//assets.pinterest.com/js/pinit.js';↩
  1336. f.parentNode.insertBefore(p, f);↩
  1337. }(document));↩
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  1340. ↩
  1341. <!-- Infolinks ad support -->↩
  1342. <script> var infolinks_pid = 3267443; var infolinks_wsid = 0; </script> <script async src="//resources.infolinks.com/js/infolinks_main.js"></script>↩
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  1345. </html>

Used the schema for HTML + SVG 1.1 + MathML 3.0 + RDFa 1.1.

Used the HTML parser. Externally specified character encoding was UTF-8.

Total execution time 403 milliseconds.

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