WEP
Wired Equivalent Privacy
The original Wi-Fi security protocol from 1997 — completely broken and deprecated. WEP's RC4 encryption with a 24-bit IV is crackable in under 60 seconds with freely available tools. Any network using WEP has no effective encryption and should be upgraded to WPA2 or WPA3 immediately.
WEP was ratified as part of the original IEEE 802.11 standard in 1997. It uses the RC4 stream cipher with a 24-bit Initialization Vector (IV) prepended to each packet. The IV was chosen to prevent keystream reuse — but 24 bits only provides ~16 million unique values. On a moderately busy network, IVs repeat within minutes. Researchers Scott Fluhrer, Itsik Mantin, and Adi Shamir published the FMS attack in 2001 showing that certain "weak" IV values leak information about the RC4 key. By 2007, the Pyshkin-Tews-Weinmann attack reduced the required packets to ~40,000 — collected in seconds on a busy network. WEP offers essentially no security.
Wi-Fi security protocol comparison
| Protocol | Year | Cipher | Status |
|---|---|---|---|
| WEP | 1997 | RC4 + 24-bit IV | Broken — do not use |
| WPA (TKIP) | 2003 | RC4 + TKIP | Deprecated — avoid |
| WPA2-TKIP | 2004 | RC4 + TKIP | Deprecated — avoid |
| WPA2-AES (CCMP) | 2004 | AES-128 CCMP | Secure — recommended minimum |
| WPA3-SAE | 2018 | AES-128/256 + SAE | Best available — use where supported |
Why WEP cannot be fixed
WEP's failure is not a bug that can be patched — it is a fundamental design flaw in how RC4 is used. The 24-bit IV space is too small to avoid reuse, and RC4's key scheduling algorithm makes certain IVs particularly revealing. TKIP (used in early WPA) was designed as a band-aid to fix WEP on existing hardware: it added per-packet key mixing to prevent weak IVs and a message integrity check (MIC) called Michael to detect forgery. TKIP is also now deprecated because RC4 remains vulnerable. The only secure solution is WPA2 with AES-CCMP or WPA3 — both use fundamentally different and unbroken cryptographic primitives.
Frequently Asked Questions
Why is WEP considered broken?
The 24-bit IV space causes reuse within minutes on a busy network. When IVs repeat, RC4 keystream can be recovered statistically. Aircrack-ng cracks WEP keys in under 60 seconds from ~40,000 captured packets. The attack is on the protocol design — no configuration or key length can fix it.
What replaced WEP?
WPA (2003, RC4+TKIP — interim fix), then WPA2 (2004, AES-CCMP — properly secure), then WPA3 (2018, SAE — prevents offline dictionary attacks). Use WPA2-AES minimum; WPA3 where supported. TKIP in any form is also deprecated.
Is it safe to use WEP if I have a strong password?
No. Password/key strength is irrelevant — WEP attacks exploit IV reuse in RC4, not brute force. A 128-bit WEP key is cracked as easily as a 40-bit key. Treat any WEP network as completely open. Upgrade to WPA2 or WPA3 immediately.