hi, I hope someone can help me.

[ppabel1]

hi, I hope someone can help me.

I have a BT ADSL Router with 5 static IP Addresses.

I also have a LAN with about 11 computers on it. They all log on to a windows 2000 domain.

how can i let everyone use this internet connection with out changing my domain name or changing every bodies IP address and sub net mask

BT have said i can in effect have 5 LAN's connected the router. And keep my existing IP format for all my machines (192.198.16.1)

but wouldnt give me details on how to do this and to be honest i am not too clued up on routers.


many thanks in advance.

 

[ChrisAC]

You need a NAT device between your router and your internal network. You won't need to change your internal IP range but you will need a multihomed device (small office firewall, NT, Linux etc..) to do NAT between your private LAN and the public IP.

Chris.
************************
Chris Andrew, CCNA
chris@iproute.co.uk
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[ppabel1]

does it matter that bt have given me a seperate subnet mask to use for this router?

 

[ChrisAC]

No. I presume that the mask is 255.255.255.248 giving you six IP addresses, of which one will be used for the router leaving you with five usable.

The ethernet port on the router should have one IP address with a 255.255.255.248 mask. To this you connect your firewall/proxy/NAT device. You configure the interface that connects to the router with another IP address from the range with the /29 mask (as above). You then configure the inside interface of your firewall with an address off your private LAN, 192.168.16.x 255.255.255.0. This address will be the gateway for your LAN. Your firewall should have a default route via the BT router that it connects to. The firewall should then NAT all internal addresses to it's routeable public address.


LAN ----- Firewall ------ BT Router --------- Internet

Good luck.

Chris.
************************
Chris Andrew, CCNA
chris@iproute.co.uk
************************

 

[ppabel1]

cheers chris for your help,

dont suppose you know how much a router shoudl cost that will do the job?

doeesnt matter if you dont

 

[ppabel1]

if i put a router in between the my Lan and the Internet connection, will i still be able to create a VPN connection to my LAN accross the internet from other locations

 

[ChrisAC]

It all depends on how you implement the VPN. You could put a firewall behind the BT router that could provide NAT, security and could be used as a VPN endpoint. When we're not putting firewalls in (firewall-1) we do put in NetPilots for small networks which can also be a VPN server. The external address of the gateway/firewall would be the VPN gateway for remote VPN connections.

Chris.
************************
Chris Andrew, CCNA
chris@iproute.co.uk
************************