SECURITY · FIELD GUIDE
Your login screen is now your perimeter.
Most people think login security means having a password. In reality, there are many authentication styles — and they’re not all equally secure.
Basic credential flows
Username + password only
You sign in with just a username and password.
Traditional login
Password + SMS code
A one-time code is sent to your phone via SMS.
Text message code
Password + authenticator app
A rotating code from an authenticator app.
Google Authenticator, Authy, 1Password
Password + push approval
Approve a login by tapping a prompt on your device.
Google Prompt, Duo Push, Microsoft Authenticator
Password + hardware security key
A physical security key verifies your identity.
YubiKey, Titan, FIDO2 keys
SMS codes are bypassable via SIM-swap. Authenticator apps raise the bar. Push prompts are strong but vulnerable to prompt fatigue. Hardware keys are the current gold standard — an attacker has to physically hold the device.
Single Sign-On (SSO)
Sign in with Google
Authenticate with your Google account.
Workspace, consumer Google accounts
Sign in with Microsoft / Entra
Authenticate with a Microsoft work or personal account.
Office 365, Entra ID
Sign in with Apple
Authenticate with your Apple ID.
Apple ID, Hide My Email
Corporate identity provider
Authenticate through your organization's IdP.
Okta, Auth0, OneLogin, Ping, SAML, ADFS
SSO centralizes policy: one place to enforce MFA, geo-restrictions, and revocation. The tradeoff is concentration — if the identity provider is compromised, everything downstream is exposed. Lock down the IdP itself with phishing-resistant MFA.
Passwordless authentication
Magic link via email
A unique sign-in link is emailed; click to sign in.
Magic link via email
One-time code via email or SMS
A one-time code is sent to your email or phone.
Code via email or SMS
Passkeys / device-bound auth
Public-key cryptography tied to your device. Phishing-resistant.
Apple/Google passkeys, FIDO2 platform authenticators
Magic links and email codes inherit the security of the email account. Passkeys are different: public-key crypto bound to a device, immune to traditional phishing. The catch is recovery — if losing a device just triggers a password-reset email, you've reintroduced the weakness you removed.
Key takeaways
Not all logins are created equal. Some are dramatically stronger than others.
Stronger authentication significantly reduces the risk of account takeover.
Choose the strongest practical option for your users and your organization.
The important question isn't "Do we have MFA?" It's "Which login methods are we allowing — and how secure are they really?" A company with strong security keys but weak SMS fallback options may still be vulnerable, because attackers don't go through the front door. They find the exception.
Modern cybersecurity increasingly comes down to identity management. Your login screen is now your perimeter. Every method you allow is a door — make sure each one is strong enough to hold.