In 12.04.x proposed there is patched wpasupplicant package, which solves the problem to 90 percent. Give it a try! There are random disconnects, but it is stable most of the time. From my experience the 5 GHz channel are more stable than the 2 GHz ones. Furthermore there are different kernel patches since 3.9.5 to get a faster authentication during direct probing => see text; wpasupplicant (0.7.3-6ubuntu2.2) precise-proposed; urgency=low * Multiple patches to reduce the number of disconnections for WPA Enterprise roaming and Opportunistic Key Caching. (LP: #1187524) * In debian/patches: 0001-sme-fix-retry-after-auth-assoc-timeout-failure.patch, 0002-sme-optimize-recovery-from-common-load-balancing-mechanisms.patch, 0003-sme-blacklist-bss-on-first-failure-if-only-a-*.patch, 0004-sme-extend-load-balancing-optimization-in-bss-blacklisting.patch, 0005-sme-optimize-recovery-from-association-command-failures.patch, 0006-sme-add-timers-for-authentication-and-association.patch, 0007-sme-nl80211-set-cipher-suites.patch: Cherry-pick patches fixing SME (Session Management Entity) for the nl80211 driver, which works as a basis for the OKC patches. * In debian/patches: 0001-pmkokc-Set-portValid-TRUE-on-association-for-driver-based-4.patch, 0002-pmkokc-Clear-WPA-and-EAPOL-state-machine-config-pointer-on-.patch, 0003-pmkokc-Clear-driver-PMKSA-cache-entry-on-PMKSA-cache-expira.patch, 0004-pmkokc-Flush-PMKSA-cache-entries-and-invalidate-EAP-state-o.patch, 0005-pmkokc-Fix-proactive_key_caching-configuration-to-WPA-code.patch, 0006-pmkokc-RSN-Add-a-debug-message-when-considing-addition-of-O.patch, 0007-pmkokc-Clear-OKC-based-PMKSA-caching-entries-if-PMK-is-chan.patch, 0008-pmkokc-Move-wpa_sm_remove_pmkid-call-to-PMKSA-cache-entry-f.patch, 0009-pmkokc-Use-PMKSA-cache-entries-with-only-a-single-network-c.patch, 0010-pmkokc-PMKSA-Do-not-evict-active-cache-entry-when-adding-ne.patch, 0011-pmkokc-PMKSA-Set-cur_pmksa-pointer-during-initial-associati.patch, 0012-pmkokc-PMKSA-make-deauthentication-due-to-cache-entry-remov.patch, 0013-pmkokc-PMKSA-update-current-cache-entry-due-to-association-.patch: Cherry-pick patches to properly do OKC (Opportunistic Key Caching) which helps maintaining connectivity on networks secured with WPA Enterprise, especially on nl80211-based drivers -- these patches require SME, and add or fix key caching and handling of the cache entries. * debian/patches/force-enable-okc.patch: force Opportunistic Key Caching to be enabled. * debian/patches/less-aggressive-roaming.patch: use less aggressive roaming settings to avoid switching to another AP unnecessarily, when the actual signal level difference is small. * debian/patches/wpa_supplicant-dbus-null-error.patch: Don't send NULL to dbus_message_new_error(). * debian/patches/0001-nl80211-Fix-UNSPEC-signal-quality-reporting.patch: fix marking qual as invalid rather than signal level. * debian/patches/wpa_supplicant-squelch-driver-disconnect-spam.patch: recover cleanly from streams of disconnect messages (like on iwl3945). * debian/patches/wpa_supplicant-assoc-timeout.patch: increase association timeouts. -- Mathieu Trudel-Lapierre