Since the AIR-AP1120B is no longer available (new) what replaces it?
The 1120 was replaced by the 1130. The 1130 will be replaced by the 1140. You can still purchase the 1130 and 1140 has been available since mid-2009. The main difference for the two is the latter, the 1140, supports 802.11n.
Cisco Aironet 1130AG 802.11 A/B/G Series Access Point
Cisco Aironet 1140 802.11 N Series Access Point
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