Home Security & Cybersecurity Glossary

The encryption standard used by password managers, VPNs, and secure messaging apps to protect stored and transmitted data. AES-256 means the encryption key is 256 bits long — effectively unbreakable with current computing power. When a product says "bank-grade encryption," it almost always means AES-256. This is the same encryption standard used by the U.S. government for top secret classified information.

Amazon's voice assistant, built into Echo speakers and Fire TV. Alexa can arm/disarm Ring Alarm, control smart locks, trigger security camera views, and run automation routines. Most Ring and many third-party security devices work with Alexa natively. Privacy note: Alexa processes voice commands on Amazon's servers by default.

The U.S. standard for rating the physical security and durability of door locks. Grade 1 is the strongest (commercial-grade), Grade 2 is mid-range (residential-quality), Grade 3 is light-duty (cheapest locks). Grade 1 locks must withstand 250,000 open/close cycles and resist significant kick-force. When choosing smart locks, always prioritize Grade 1 — many smart locks are only Grade 2 despite their price.

A programming interface that allows different apps and devices to communicate with each other. When a smart home device has an "open API," it means third-party developers can integrate it into custom automations. Many enthusiast home security setups use APIs to connect security cameras to Home Assistant, or smart locks to custom dashboards.

A secondary communication path for security systems that uses cellular radio (like a mobile phone) instead of home internet. Critical for continued protection during internet or power outages — the most common time burglars strike. Ring Alarm Pro and most ADT systems include cellular backup. SimpliSafe charges extra for it. Without cellular backup, cutting your internet or power line disables cloud-connected alarms.

Using a physical characteristic — fingerprint, face, iris, or voice — to verify identity. Smart locks use fingerprint sensors as one of multiple unlock methods. Phones use Face ID or Touch ID. Biometrics are convenient but not foolproof — high-quality photos can sometimes fool face recognition, and fingerprints can be lifted. Best used as one layer of a multi-factor setup, not the only protection.

Professional 24/7 monitoring service where trained operators watch for alarms and dispatch police, fire, or medical services when triggered. Costs $10–$50/month depending on the company. UL-listed central stations are independently certified for reliability. ADT, Vivint, and SimpliSafe all use UL-listed central stations. Self-monitoring (getting push notifications yourself) is cheaper but puts response responsibility on you.

Small text files websites store on your browser to remember your preferences or track your activity across sites. First-party cookies (from the site you're visiting) are generally benign — they keep you logged in. Third-party cookies (from advertisers) track you across multiple websites to build a behavioral profile. Privacy-focused browsers like Firefox and Brave block third-party cookies by default.

IP (Ingress Protection) ratings describe how well a device resists dust and water. For outdoor security cameras and smart locks, look for IP65 or higher. IP65 = dust-tight, protected from water jets. IP67 = can be submerged up to 1 meter for 30 minutes. IP68 = deeper/longer submersion. The first digit (1–6) is dust protection; the second (1–8) is water protection. A doorbell rated IP44 is not suitable for exposed outdoor use.

A free tool that prevents new credit accounts from being opened in your name without your explicit unfreeze permission. Unlike a fraud alert (which merely requests extra verification), a credit freeze blocks all new credit inquiries — even legitimate ones you initiate. Free at all three bureaus (Equifax, Experian, TransUnion) since 2018. You can unfreeze temporarily when you need to apply for credit. The most effective preventive step against identity theft.

A home security system you install yourself without professional installation fees. DIY systems like SimpliSafe, Ring Alarm, and Abode are designed for self-installation — most take under an hour. They often cost significantly less than professionally installed systems (ADT, Vivint) while offering comparable monitoring quality. The trade-off: you're responsible for sensor placement and troubleshooting.

The internet's phone book — translates human-readable domain names (silentsecurity.com) into IP addresses computers use. Your default DNS server is usually your ISP, which can log every website you visit. Privacy-focused alternatives like Cloudflare (1.1.1.1), Google (8.8.8.8), or NextDNS encrypt your queries and block ad/tracking domains. Changing your router's DNS is one of the simplest home network privacy improvements.

Encryption where only the sender and recipient can read the message — not the service provider, government, or anyone who intercepts it. Signal, WhatsApp (for messages), and Apple iMessage use E2EE. Ring added optional E2EE for video in 2021 — useful but disables some features like shared-device viewing. When evaluating security cameras, check if video storage is end-to-end encrypted (very few are by default).

Automated systems that detect the initial P-wave of an earthquake and send alerts seconds before stronger S-waves arrive. The USGS ShakeAlert system covers the U.S. West Coast. Even 10–30 seconds of warning is enough to Drop, Cover, and Hold On before shaking starts. In Japan, the JMA system can provide over a minute of warning for distant earthquakes. ShakeAlert alerts appear via Wireless Emergency Alerts on modern smartphones.

When a security system triggers a police or fire dispatch that turns out to be unnecessary. Many cities charge fees for repeated false alarms — some as high as $100–$300 per incident. Modern security systems use intelligent verification (video confirmation, dual-tech sensors, and entry delay timers) to reduce false alarms. ADT's self-dispatch model and Ring's Motion Verification (video clips before dispatch) both address this. Always use entry/exit delays and test your system regularly.

Software or hardware that monitors and controls incoming/outgoing network traffic based on security rules. Your home router has a basic built-in firewall. Next-gen firewalls (like those in Eero Pro, UniFi, or pfSense setups) inspect traffic content, block known malicious domains, and can segment IoT devices onto a separate network. For home use, enabling your router's firewall and keeping firmware updated is the minimum. For advanced protection, consider a dedicated device like a GL.iNet router running AdGuard.

A virtual boundary around a geographic location that triggers automations when a device enters or leaves. In home security, geofencing automatically arms your system when you leave and disarms when you return — using your phone's GPS. Ring, SimpliSafe, and Abode all support geofencing. Limitation: GPS accuracy can vary 10–50 meters, occasionally causing early/late triggers. Works best on Android; iOS background location restrictions can delay triggers.

Video technology that captures detail in both very bright and very dark areas simultaneously. Critical for outdoor security cameras where sunlight creates harsh shadows on a porch. Without HDR, a backlit face looks like a silhouette. With HDR, you see facial features clearly even when someone is standing in front of a bright window. The Google Nest Doorbell and Arlo Pro 4 both feature HDR. Look for HDR in any camera that faces south or has a bright background.

A free service (haveibeenpwned.com) by security researcher Troy Hunt that checks whether your email address or password has appeared in known data breaches. Over 12 billion records from hundreds of breaches are indexed. Bitwarden integrates directly with HIBP to flag passwords that appear in breach databases. Check your email regularly — if it appears in a breach, change the relevant passwords immediately and watch for phishing emails.

The collective term for internet-connected devices that aren't traditional computers — smart locks, cameras, thermostats, doorbells, sensors, and appliances. IoT devices are a major home network security risk because they often have weak default passwords, infrequent firmware updates, and broad network access. Best practice: put all IoT devices on a dedicated guest/IoT VLAN, change default passwords, and keep firmware updated. Never expose IoT devices directly to the public internet.

The physical control panel for a security system that allows arming, disarming, and status checking. Modern keypads include touchscreens, proximity card readers, and PIN entry. Keypad placement matters: it should be at the main entry point with enough view to see who's entering, but not visible through windows (which reveals your system type to potential intruders). Most DIY systems use wireless keypads powered by rechargeable batteries.

Video footage stored on a physical device in your home — SD card, NVR (Network Video Recorder), or NAS (Network Attached Storage) — rather than in the cloud. Local storage means no monthly subscription fees and footage remains accessible even if the camera manufacturer goes out of business. Trade-offs: if a burglar steals the NVR, footage is gone; cloud backup doesn't have this problem. Best setups use both: local storage plus cloud backup of key clips.

Encrypts every piece of data on a hard drive so it's unreadable without the decryption key. macOS uses FileVault, Windows uses BitLocker, Linux uses LUKS, and VeraCrypt works cross-platform. Essential for laptops — if your laptop is stolen, full disk encryption prevents the thief from accessing your files by removing the drive. Enable it in your system preferences; the performance impact on modern hardware is negligible.

An open smart home standard backed by Apple, Google, Amazon, and Samsung that enables devices from different ecosystems to work together without proprietary bridges. A Matter-certified smart lock works with Google Home, Apple Home, and Amazon Alexa simultaneously — you're not locked into one ecosystem. Launched in 2022, Matter devices use either Thread (battery-efficient mesh) or Wi-Fi. Look for Matter certification when buying new smart home devices for maximum future compatibility.

Requiring two or more forms of verification to log in: something you know (password), something you have (phone with authenticator app or hardware key), or something you are (fingerprint). MFA stops 99.9% of automated account attacks (Microsoft statistic). TOTP authenticator apps (Google Authenticator, Authy, Raivo) are more secure than SMS codes, which can be intercepted via SIM-swapping attacks. Hardware keys (YubiKey) are the most secure form of 2FA.

A defined area within a camera's field of view that triggers motion alerts. You draw zones to cover your driveway but exclude the sidewalk where passing pedestrians would constantly trigger false alerts. Finer-grained motion zones reduce alert fatigue — you only get notified about what matters. Ring calls these "Motion Zones," Nest calls them "Activity Zones," Arlo calls them "Activity Zones." Look for polygon-based zones (draw any shape) over grid-based zones (limited rectangles).

The U.S. federal agency that publishes cybersecurity standards widely adopted by both government and private industry. The NIST Cybersecurity Framework provides a voluntary risk management structure for organizations. NIST SP 800-63B (2017, updated 2024) governs password policy: NIST now recommends length over complexity — a 15-character passphrase is better than an 8-character "P@ssw0rd." NIST also advises against periodic forced password changes unless a breach is suspected.

A VPN's claim that it doesn't record user activity — which IP addresses you connected from, what websites you visited, or when you were online. The claim alone is meaningless; verification matters. Look for VPNs with independent audits from firms like Cure53 or Deloitte that have verified the no-logs policy technically — not just reviewed the privacy policy. Real-world proof: Mullvad has been physically raided by police and had nothing to hand over.

A dedicated device that receives video streams from IP cameras over your home network and stores them locally. Unlike DVRs (which use analog cameras), NVRs work with modern Wi-Fi and PoE (Power over Ethernet) cameras. A 4-channel NVR can record 4 cameras simultaneously 24/7 to a hard drive you own. No subscription fees. Popular NVR solutions: Synology NAS with Surveillance Station, Reolink NVR, or open-source options like Frigate (runs on a Raspberry Pi). Best for users who want complete control.

Software whose source code is publicly available for anyone to inspect, audit, and contribute to. In security contexts, open source is a significant trust advantage — vulnerabilities can't hide in public code, and thousands of independent researchers can review it. Bitwarden (password manager), Signal (messaging), and WireGuard (VPN protocol) are open source. This doesn't mean open source is automatically secure — it still requires active audits and maintenance — but it enables independent verification that closed-source products cannot provide.

A new authentication standard (based on FIDO2/WebAuthn) that replaces passwords with cryptographic keys stored on your device. When you log in with a passkey, your device proves your identity using a private key that never leaves your device — unlike passwords, passkeys can't be phished or stolen in database breaches. Supported by Apple, Google, and Microsoft on modern devices. 1Password, Bitwarden, and Dashlane all support storing passkeys. The future of authentication.

A function that converts your master password into an encryption key by running it through a hash function thousands of times (called "iterations"). More iterations = harder for attackers to brute-force your master password if the encrypted data is stolen. NIST recommends at least 600,000 iterations. Bitwarden uses 600,000 by default. The 2022 LastPass breach exposed why this matters: accounts with low iteration counts (LastPass had some users at only 5,000 iterations) are vulnerable to cracking.

The most common motion detection technology in home security — detects changes in infrared (heat) radiation, which living beings emit. A PIR sensor triggers when a warm body (person, pet) moves across its detection zones. Pet-immune PIR sensors use signal processing to ignore animals under 40–55 lbs by factoring in the heat signature's size and movement pattern. Dual-tech sensors pair PIR with microwave detection for lower false alarm rates.

A social engineering attack where an attacker impersonates a trusted entity — your bank, Amazon, or even your IT department — to trick you into revealing credentials or clicking a malicious link. 90% of data breaches start with phishing (IBM). Spear phishing targets specific individuals with personalized content. Vishing is voice phishing by phone. Smishing is SMS phishing. Defense: be skeptical of unexpected requests, verify via a separate channel, use a password manager (which won't autofill credentials on fake sites), and enable MFA.

A technology that delivers electrical power to devices through an Ethernet cable, eliminating the need for a separate power adapter. PoE security cameras are the gold standard for reliability — a single Cat5e or Cat6 cable handles both power and data. You need a PoE switch or PoE router to supply power. Popular with Reolink, Hikvision, and Ubiquiti camera systems. Compared to Wi-Fi cameras: no connectivity drops, no battery changes, tamper-proof wired connection.

Malware that encrypts your files and demands payment to restore access. Ransomware attacks cost businesses and individuals billions annually. The best defense is the 3-2-1 backup rule: 3 copies of data, on 2 different media types, with 1 copy offsite (or in the cloud). For home users: automatic cloud backup (Backblaze, iCloud) plus a local external hard drive. Attackers target backups first, so ensure your cloud backup can't be deleted from a compromised machine (immutable backups).

Contactless card or key fob entry technology used by commercial buildings and some smart locks. RFID (Radio Frequency Identification) uses passive cards energized by a reader. NFC (Near-Field Communication) is the phone-based version used by Apple Wallet and Google Wallet. Apple Home Key (on Schlage Encode Plus, Yale Assure Lock 2) uses NFC — tap your iPhone or Apple Watch to unlock. More secure than traditional RF key fobs, which can be cloned with cheap hardware.

The 1–5 scale used to classify Atlantic hurricanes by sustained wind speed. Category 1 (74–95 mph) causes minor damage. Category 3+ (111+ mph) is "major hurricane" territory. Category 5 (157+ mph) causes catastrophic damage to well-built homes. The scale rates wind only — it does not account for storm surge, which kills more people than wind. A Category 2 storm making landfall near a bay may cause worse flooding than a Category 4 hitting open coast.

An attack where a criminal convinces your mobile carrier to transfer your phone number to a SIM card they control. Once they have your number, they receive your SMS two-factor authentication codes and can reset accounts. High-profile crypto thefts and social media hijackings commonly start with SIM swaps. Defense: switch from SMS 2FA to an authenticator app (TOTP) or hardware key, set a carrier PIN/passphrase with your mobile provider, and use a Google Voice number for 2FA codes.

Many modern security systems integrate smoke and carbon monoxide detectors into the central monitoring system, so a CO or fire alarm triggers professional dispatch — not just a local beep. The NFPA recommends interconnected detectors so when one alarms, all alarm. Z-Wave smart smoke detectors (First Alert Z-Wave, Kidde) can send phone alerts. Nest Protect integrates with Google Home and sends phone push notifications with location (which room triggered). Replace all detectors every 10 years.

A low-power mesh networking protocol designed for IoT devices, often used alongside the Matter smart home standard. Unlike Wi-Fi devices that connect directly to your router, Thread devices form a mesh — each device extends the network range. Requires a Thread Border Router (built into Apple HomePod mini, Apple TV 4K, and Google Nest Hub Max). Thread is ideal for battery-powered sensors and locks that need reliability without draining quickly on Wi-Fi.

A 6-digit code generated by an authenticator app (Google Authenticator, Authy, Raivo OTP) that changes every 30 seconds. Based on a shared secret key and the current time — both the server and your app independently generate the same code. Much more secure than SMS 2FA because TOTP codes can't be intercepted by SIM swapping and don't require cellular service. Store your TOTP backup codes in a secure offline location — losing your phone without backup codes can lock you out permanently.

A security principle requiring two people to independently authenticate or approve a sensitive action. Used in nuclear weapons, financial transactions, and high-security vaults. In home security context: some smart lock systems require two PIN entries from two different users to unlock, or two-step confirmation before a vault opens. For cybersecurity, password manager Emergency Access (Bitwarden, 1Password) creates a dual-authorization system for vault recovery.

A technique that divides a single physical network into multiple isolated virtual networks. In home security: put all smart home / IoT devices on a separate VLAN from computers and phones. If a smart thermostat is compromised, the attacker can't access your laptop because they're on different network segments. Supported by Eero Pro (called "IoT" network), UniFi (VLANs), and most prosumer routers. Setting this up is the single best thing you can do for home network security.

A service that encrypts your internet traffic and routes it through a server in a location you choose, masking your IP address from websites and your ISP. VPNs don't make you anonymous — your VPN provider sees your traffic instead of your ISP. A good VPN protects against ISP tracking, prevents man-in-the-middle attacks on public Wi-Fi, and bypasses geographic content restrictions. Choose VPNs with verified no-logs audits (Mullvad, NordVPN, Proton VPN) — not marketing claims alone.

Two different levels of weather alerts with very different meanings. A Watch means conditions are favorable for the hazard to develop — you have time to prepare and should monitor updates. A Warning means the hazard is imminent or occurring — take action now. A tornado Watch: conditions exist for possible tornadoes, prepare shelter. Tornado Warning: a tornado has been spotted or indicated by radar — take shelter immediately. This distinction can save your life.

A modern, fast VPN protocol with ~4,000 lines of code (vs OpenVPN's 400,000+) — fewer lines means a smaller attack surface and easier security audits. WireGuard uses state-of-the-art cryptography (ChaCha20, Poly1305, Curve25519) and is 2–4x faster than OpenVPN in benchmarks. Mullvad, NordVPN (NordLynx), and Proton VPN all support WireGuard. If your VPN client offers WireGuard, use it — it's the current gold standard for speed and security.

A low-power mesh wireless protocol specifically designed for smart home devices, operating on the 908 MHz band (in the U.S.) — away from congested 2.4 GHz Wi-Fi. Z-Wave devices form a self-healing mesh network where each device extends range. Maximum mesh network of 232 devices. Popular in professional security systems (ADT, Abode) and premium smart locks. Devices require a Z-Wave hub (SmartThings, Hubitat, Home Assistant with Z-Wave stick). More reliable than Zigbee in environments with lots of Wi-Fi interference.

A low-power mesh wireless protocol operating at 2.4 GHz, widely used in smart home sensors, smart bulbs (Philips Hue), and locks. Zigbee devices mesh like Z-Wave — each powered device extends coverage. Larger maximum mesh than Z-Wave (65,000 devices) and open standard. Downside: operates in the crowded 2.4 GHz band alongside Wi-Fi and Bluetooth, which can cause interference. Used in Amazon Echo (Zigbee hub built in), Samsung SmartThings, and Home Assistant. Abode Iota supports Zigbee natively for broad sensor compatibility.