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Community Member

Is modem needed to connect to internet ?

Is it necessary for me to use a modem to connect to the internet ?? or i can do without ?? can i connect to the internet using a router if i am using a T1 line ??

Community Member

Re: Is modem needed to connect to internet ?

what type of connectivity is that ?

whether your router is having built-in modem and T1 card ?.

If you have modem means , routing to be enabled at ISP side , you have to configure ip addresses at both the end.


Re: Is modem needed to connect to internet ?

Case1 : Modems are typically used to connect to internet by connecting the phone line to a PC or laptop with built in modem (or external modem) and having a dialup account with an ISP.

Case 2:YOu can also hook up the phone line to a router with modem card and configure the router to dial out to the ISP. Your PCs will connect using an ethernet card (connected to a switch). The router's ethernet will also be connected to the same switch. You can then set the router as default gateway and configured NAT on the router to access the internet.

Case 3: If you have a T1 line, the scenario is the same as Case 2. The phone line will be replaced by the T1 line.

In case 1 and 2, bandwidth is restricted to 56k (max). In case 3, you will get bandwidths of upto 1.5 Mbps (full T1).


Community Member

Re: Is modem needed to connect to internet ?

Case 3 is something i have in mind. i am looking at IP VPN service offer by my ISP. what are the router that support vpn that you recommand ??? If i wanted to have a firewall, how should i implement it ??

computers ---> switch ----> firewall ---> router or

computers ---> switch ----> router ---> firewall ---> router

Re: Is modem needed to connect to internet ?


would suggest the first block diagram which you have mentioned in your post in which your local lan is behind your Firewall and nothing is exposed to the outside world except the outside interface of the firewall which is by default connected to the outside world through the router.

Again there are few considerations here in getting your vpn connectvitiy,with the above scenario you can get you VPN tunnel dropped either in the router interface itself or into the firewall.

It again depends on the type of firewall whic you will be deploying out there.

Regarding the router model and the type i would better suggest to look on something like Cisco 1721 or above to cater your needs since you got to have T1 connectivity also i would suggest to lookin for a backup connectivity in case of some issues or probs with the main link.

Again the same 1721 can be a best bet to have the backup module(ISDN) installed in it .


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