T1 Question

chmorin

I'm helping someone with the following:

They have a server on their LAN which other applications see in order to work. They have a few remote users that will need access to the server soon. I plan on implementing the following to resolve it:

Open VPN connection.
Point Application to the same LAN Address of the server.

First question is, is this a viable solution?

Second is, they have a T1 line with a 4 Phone lines and 2 Data lines. Does this mean that they can only have two active connections outside at once? I'm not sure as to the data side of a T1. I would figure it would multiplex somehow.

hypnotoad

chmorin wrote: »

I plan on implementing the following to resolve it:

Open VPN connection.
Point Application to the same LAN Address of the server.
First question is, is this a viable solution?

Yes and no...what device "terminates" the T1 right now? Most of the time, the server will sit behind the router and the router will apply some services to the connection, such as NAT, VPN, or firewall.

chmorin wrote: »

Second is, they have a T1 line with a 4 Phone lines and 2 Data lines. Does this mean that they can only have two active connections outside at once? I'm not sure as to the data side of a T1. I would figure it would multiplex somehow.

Depends on how they've divided up the DS0 channels. A T1 will give you up to 23 or 24 channels (depending on the type)...it can also be fractional (a partial T1). Not quite sure about the 4 lines and 2 lines thing for voice and data?

chmorin

hypnotoad wrote: »

Yes and no...what device "terminates" the T1 right now? Most of the time, the server will sit behind the router and the router will apply some services to the connection, such as NAT, VPN, or firewall.

The T1 goes to a Cisco IAD 2400. It's fa0/0 port goes to a 24 port linksys switch. I have not gotten my hands into the gateway yet. I would assume to find NAT inside of there at a min. I doubt there is any VPN configurations, but I wouldn't know them if I saw them probably. I plan on using No-IP - Dynamic DNS, Static DNS for Your Dynamic IP to give them a static hostname for their dynamic IP and then use OpenVPN - Open Source VPN to create a VPN connection.

hypnotoad wrote: »

Depends on how they've divided up the DS0 channels. A T1 will give you up to 23 or 24 channels (depending on the type)...it can also be fractional (a partial T1). Not quite sure about the 4 lines and 2 lines thing for voice and data?

My guess is it is a fractional T1, I have no idea bout the 4 lines and 2 lines thing. My guess is it is using CAS as that is the norm for our location. I would prefer not to call the ISP and ask these questions but if it may be an issue having people connect from the outside I'll give them a call.

hypnotoad

Most ISPs offering T1 service offer static IPs with them. As a business-class connection, they should at least give you a static IP. Anyway, you could register a domain name and run a name server and not have to use no-ip.org if you had a static IP.

I dont know if an IAD will run VPN...I kind of doubt it...in which case you could static NAT to an inside VPN device (say, a windows 200x server running PPTP vpn) and achieve basically the same results.

hypnotoad

Also, you could look in the phone system and see how many ports are dedicated to the trunk group to figure out the 2/4 thing. What kind of phone system is it?

chmorin

hypnotoad wrote: »

Also, you could look in the phone system and see how many ports are dedicated to the trunk group to figure out the 2/4 thing. What kind of phone system is it?

I'll look into it a little more and update you. Thanks for your help!

drkat

look at the T1 in the router you'll be able to see how it's configured.

drkat

2 lines on a T1 would be 64K or 56K each respectively. look at the timeslots allocated in the router config - without seeing a config I wont be much help there are so many ways of handing off a T1 to do both voice/data - you may have a CSU in front of your cisco depending how you're handing it off to the phone system.