Hi all,
We have a Cisco 3640 router connected to branchs by ISP's MPLS network. We have also 6 Catalyst 3548XL switchs connected together to form a LAN. We use PIX 515 with PAT as firewall. The network layout is illustrated below:
branchs---ISP MPLS---3640 Router PIX---adsl modem---Internet | | switch1.. to.. switch6 | | wireless router lots of PCs and web server | wireless users
We want to launch wireless function to some staffs to surf the Internet. After installing and configuring Buffalo wireless router(with NAT), the wireless connection worked fine. But after a period of time, wireless users couldn't access the Internet(IE for example) BUT I could access internal web server connected to those internal switchs. I found when I closed the IE windows then opened a new IE windows again, I could browsed the Internet again..........
I replaced Buffalo wireless router with Belkin wireless router to test, the result is the same(i.e. after browsing Internet by IE a period of time, I couldn't access Internet anymoe except for internal web server. I need to close IE and open a new IE to access Internet again).
I suspect it is because PIX(or my 3640 router)blocks those wireless connection SINCE I am able to access the internel web server without any problem.
Is it possibly caused by NAT? We have two NATs enabled. One is on wireless router and the other is on PIX. Or it is caused because my 3640 router doesn't forward traffic for those wireless connections?
BTY, the default gateway of wireless router is set to 3460 router.