Frequently Asked Questions

Does my computer need anything special hardware to work with ISDN ??

Your computer will connect to the ISDN modem via Ethernet. If your computer is already connected to a local area network (LAN), or has an unused network interface connector (NIC) your computer can be connected to ISDN. If you don't already have a NIC in your computer, you will have to install one. NIC(s) can be purchased from almost all computer suppliers.

Note: Some ISDN modems use the serial port for connection with the computer, not Ethernet.

Does my computer need anything special software to work with ISDN ??

You will have to have software "drivers" to work with the NIC (see above) and the appropriate protocol for your intended use (usually TCP/IP for browsing the Internet).  TOP

I've got two (or more) computers at home, how do I use the same ISDN connection for both computers ?

In addition to the hardware and software described above for each computer, you will need an Ethernet hub. The hub will be the central connection point for each computer, and the ISDN modem, thus the hub you purchase will need enough ports for all of the computers you want to connect PLUS the ISDN modem.

Note: Because of the issue about serial ISDN modems above, it may be necessary to
have routing software installed in the computer to share a connection.  TOP

I've already got a modem in my computer, why doesn't that work for ISDN ?

Modems are unique to the underlying frequencies (i.e. dial-up, DSL, cable), medium (i.e. coaxial cable, twisted pairs, etc.), and modulation (i.e. X2, K-Flex, V.90, V.92, etc.). So, much as many of you have changed your dial-up modems to go from 28.8Kbps, to something approaching 56Kbps, you will not be able to use your dial-up modem for DSL.  TOP

How come I'm paying for ISDN 128Kbps symmetrical but when I go to www.someplace.com my browser says it's downloading at a lot slower speed ??

The ISDN (or any service) can only be provided with some degree of certainty from your location to the point of connection to the Internet. Your Internet Service Provider (ISP) should have a local speed test site that you can use to confirm the speed of your connection. Your download rate from places on the Internet will vary for a number of reasons, including (but not limited to):
· the server load at the site your are visiting
· the size / speed / utilization of the network connection the server has
· the overall utilization of the Internet "backbone" that is being utilized
· the size / speed / utilization of the connection that your ISP has to the Internet
· the speed of your computer
· the speed (and utilization) of your network if your are on a LAN
· and others.  TOP

Now that DTC has DSL, why even offer ISDN ?

These are two completely different services. DSL is a dedicated connection usually to an Internet service provider (ISP) while ISDN is by definition switched. An example of when ISDN would be appropriate would be for video conferencing to different locations at different times. Another example would be if the addition phone line is more valuable to your or your business than only intermittent use of the higher speeds.  TOP

Does my computer need anything special hardware to work with DSL ??

Your computer will connect to the DSL modem via Ethernet. If your computer is already connected to a local area network (LAN), or has an unused network interface connector (NIC) your computer can be connected to DSL. If you don't already have a NIC in your computer, you will have to install one. NIC(s) can be purchased from almost all computer suppliers.  TOP

Does my computer need anything special software to work with DSL ??

You will have to have software "drivers" to work with the NIC (see above) and the appropriate protocol for your intended use (usually TCP/IP for browsing the Internet).  TOP

I've got two (or more) computers at home, how do I use the same DSL connection for both computers ?

In addition to the hardware and software described above for each computer, you will need an Ethernet hub. The hub will be the central connection point for each computer, and the DSL modem, thus the hub you purchase will need enough ports for all of the computers you want to connect PLUS the DSL modem.  TOP

I've already got a modem in my computer, why doesn't that work for DSL ?

Modems are unique to the underlying frequencies (i.e. dial-up, DSL, cable), medium (i.e. coaxial cable, twisted pairs, etc.), and modulation (i.e. X2, K-Flex, V.90, V.92, etc.). So, much as many of you have changed your dial-up modems to go from 28.8Kbps, to something approaching 56Kbps, you will not be able to use your dial-up modem for DSL.  TOP

I've heard about T-1 service. Since DSL is as fast, or in some cases faster, why would anyone use T-1 service for Internet access ??

You are correct about the speeds, T-1 is a symmetrical (same speed in both directions) service at 1.544Mbps. Some flavors of DSL could be configured for symmetrical speeds of 1.544Mbps. There are a couple of significant differences between T-1 and DSL, one being that T-1 service is a committed data rate, i.e. the T-1 provider guarantees 1.544Mbps all the time, and monitors the circuit for failures and degradation of service. DSL data rates are "up to" whatever rate you are paying for which means that it may (and probably will) fluctuate. Another difference is that a T-1 is connected all the time. DSL (and cable modems) while physically connected all the time are not necessarily connected to the Internet all the time. DSL (and cable modems) use their extremely fast setup times to give the illusion of being connected all the time. That's the long answer to get to the point that you would probably want to connect servers and mission critical applications with T-1s and use DSL for home and business outgoing inquiries.  TOP

Since my computer is connected to the Internet most of the time, should I be concerned about security ??

You should ALWAYS be concerned about security.  TOP

All right all ready, I'm concerned about security, what are the options ??

The options here range from having network security specialists evaluate your network and supply firewalls, and other expensive stuff to turning off your computer when not in use. At a minimum, every installation should consider using a firewall, either a firewall appliance or firewall software on each computer. You should analyze your requirements and budget to determine how to proceed in the area of security.  TOP

How come I'm paying for DSL at 384Kbps down / 128Kbps up but when I go to www.someplace.com my browser says it's downloading at a lot slower speed ??

The DSL (or any service) can only be provided with some degree of certainty from your location to the point of connection to the Internet. Your Internet Service Provider (ISP) should have a local speed test site that you can use to confirm the speed of your connection. Your download rate from places on the Internet will vary for a number of reasons, including (but not limited to):

• the server load at the site your are visiting
• the size / speed / utilization of the network connection the server has
• the overall utilization of the Internet "backbone" that is being utilized
• the size / speed / utilization of the connection that your ISP has to the Internet
• the speed of your computer
• the speed (and utilization) of your network if your are on a LAN
• and others  TOP