get disconnected from a VPN?

As explained earlier, the current NESPOT is based on the 802.11b ,WLAN. However, today there are a couple of new WLAN ,versions called IEEE 802.11a [5] and 802.11g [9], which support ,the data rates in physical layer up to 54Mbps. Even though the ,standardization of IEEE 802.11a was finalized in year 1999, when ,IEEE 802.11b was finalized, the 802.11a devices became ,available in the market only in early 2002. On the other hand, the ,802.11g is a brand-new WLAN standard. One major distinction ,between 802.11a and 802.11g is the frequency bands; the 802.11a ,operates at the 5 GHz bands while the 802.11g does at the 2.4 ,GHz bands. Moreover, the 802.11g actually includes the 802.11b, ,and hence can co-exist with the 802.11b at the same channel ,without a severe problem.  ,One minor problem with the 802.11a today in Korea is the ,available frequency spectrum at the 5 GHz band. As of today, the ,Korean government allows for the WLAN to use a spectrum of ,100 MHz from 5.725 to 5.825 GHz. There exist four orthogonal ,channels of 20 MHz in this 100 MHz band. This is a much ,smaller band compared to other countries. For example, in the US, ,there exist 300 MHz band at 5 GHz, opening 12 channels for the ,802.11a. The Korean government is planning to open up more,