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LAN design help


I need help in re-designing our LAN, which is currently based on:

- 1 router (not Cisco) connected to my ISP via a 64KB leased Line.

- Windows 2000 Server with Small business server, using exchange server for the mailboxes and ISA server for the internet connectivity.

- 16 port Switch (Ethernet)

- 10 PCs connected (Windows XP Pro)

- 1 laser printer

Scenario: The current leased-line cost are very high and the speed frustrating. So, we decide to go for ISDN and ADSL and a Cisco router.

Idea: ISDN to download mail from ISP to our exchange server, ADSL for internet browsing connection from Cisco router.

- Static IP from ISP (ISDN)

- Dynamic IP from ISP (ADSL), does not support static IPs.

Question: Should we have two (2) servers or one (1) with two connections? How do we go about setting up: NAT, DHCP, proxy server?


Re: LAN design help

I would go with the ADSL line only. You should be able to connect to your ISP with thru the internet right?.


Re: LAN design help

Yes, But down here, ADSL is still a shared connection. Though, you get fast speed, one has to have a backup line (ISDN).

Thankfully, I managed to go around the exchange server setup (using POP3 instead of SMPT), which allows me to get dynamic IP addresses from my ISP. I no longer need a static IP.

The setup would be:

- 1 Server, to host the exchange server and ISA server (Windows 2000 server)

- 1 Cisco router, with ADSL & ISDN modem, and DHCP enabled

- 16 port Switch

- 10 PCs (workstations)

My question now is, how do I go about setting up the router (1700 series) to switch from the default connection (ADSL) to backup (ISDN) should bandwidth from ADSL fail?

How do you tell the router to disconnect (ISDN) when there is no activity in the network for 15 minutes?

Any help is welcomed!

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