DSL & cable
About
We do not provide any "broadband" (DSL, cable, etc) networking services for remote access, nor do we recommend any specific vendor.
The two main options for high-speed home network access are DSL and cable. Each choice has its own set of advantages and disadvantages:
| Cable | DSL | |
|---|---|---|
| Bandwidth | Shared with other cable users in the area | Dedicated line to the central office. |
| Downstream Data Flow | Variable, depending on number of active users on the cable network in your neighborhood and time of day. Best case scenario: Equal to DSL high-end. Worst case scenario: Equal to DSL low end | Average: ~384 - 768 Kbps High-end: 7.1 mbps Different providers offer many different packages. |
| Upstream Data Flow | 128 Kbps max for many providers. Also variable depending on users and time of day. | At least 128 Kbps. |
| Availability | As a general rule, this service is available in areas outside the DSL (or rural) areas. | As a general rule, this service is available in urban areas. Most service providers can only provide DSL to users who live 12 - 15 thousand feet from the local telephone company's switching station. |
| Benefits | Fast pipe, if you're the only computer geek in your neighborhood | Relatively fast pipe for all users |
| Things to Consider | Security. A sophisticated user may be able to see the packets of other users on the same shared cable segment. | The level of speed is dependent upon how far you live from the central office. You may not be eligible for the 7.1 Mbps line. |
| Cost Considerations | I may have to buy a cable modem. | I may already have a DSL modem. Will it work with my new DSL provider? |
Related documentation
- SCS VPN service
- How a remote host on another network (such as a host with a cable or DSL connection) can access services that are restricted to SCS hosts.
Additional information
These off-site links will open in a new browser window:- CMU Computer Services DSL information
- Information from CMU Computer Services about local DSL options.
- Broadbandreports.com
- FAQs and other information about broadband access, including a searchable (by zipcode) list of service providers.
- Sniffing A Cable Modem Network: Possible or Myth?
- Technical discussion of the feasibility of people on a shared cable modem segment being able to eavesdrop on network traffic.