[chicagotech]

Small company just opens a new office in a remote side. Both offices connect via T1 line and they can share each other. In the main office, they have another T1 line connecting to the Internet. However, the remote office can’t access the Internet through the main office Internet router because the ISP limits just one subnet. They have decided to change to another ISP. However, it may take a few months to switch to another ISP since the current ISP provides data and phone services. So, they called me to provide a temporary solution.

To find out how the ISP limits one subnet, I setup a USR8200 router in the main office. The LAN IP is 192.168.0.0/24 and USR8200 router inside IP is 192.168.1.0/24. From the 192.168.1.x (behind the USR router), I can ping any public IP, and TS/VPN to my office using IP addresses. However, I can’t access/ping any web sites.

By default, the DNS is USR router IP, 192.168.1.1. I changed the DNS to 4.2.2.1 and also the ISP DNS. None of them work. I event assigned the DNS (mentioned above DNS IP) manually on the computer, but could not make it work. Can I conclude that the ISP limits the DNS to subnet 192.168.0.0/24 (for example, limits outbound port 53 to 192.168.1.0.24)?

If yes, what should they do to let remote office access the internet? If not, why can’t they access the Internet?

By the way, at this time I just setup a XP computer in the main office for branch office access using RDC and from that computer go to the internet.

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Theoretically...if site2 is accessing site 1 through a site to site vpn via t1...then i would assume (unless the router in site1 is managed) that setting up a NAT rule in the router would allow for site2 to connect out to the net..but...due to your description...it sounds as though there is a managed router on site? if so...there's nothing you can do..

[dsenette]

Theoretically...if site2 is accessing site 1 through a site to site vpn via t1...then i would assume (unless the router in site1 is managed) that setting up a NAT rule in the router would allow for site2 to connect out to the net..but...due to your description...it sounds as though there is a managed router on site? if so...there's nothing you can do..