Friday, September 15, 2006

Okay, time to educate...


It's time to debunk some things about technology. For those of you who do not know me, I make an income by managing the local cable company's internet service. I'm tier 1, tier 2, and tier 3 tech support, Internet sales, network administrator, mail administrator, webmaster, and everything else that is involved with a cable ISP all in one person. The only thing I don't do is fix and install cable lines.

Every day, I get calls on my official cable internet office phone from people who have no clue about broadband technology. I answer the phone, they ask "do you offer DSL?" AAARRRRGGGHHH!!!!! (whew - I needed to do that). My answer - No, we're the cable company, we offer cable internet.

Unbeknownst to most people (thats a nice big word for some of you more educated blog people, or is it blukers - I'm still new to this), DSL isn't the blanket term for all high-speed internet service. There's FiOS (FIber Optic Service), DSL (Digital Subscriber Line), and Cable Internet just to name a few; and that's just naming some of the wireline based services.

DSL is offered by your telephone company. It's only available by a telephone line. It CANNOT be carried by Cable TV service. It transmits it's magic over copper phone lines in a frequency outside of the analog voice spectrum. It is my understanding that if you have DSL service, you have to have home telephone service. I don't work with the phone company, so I'm not too well versed on how the technology works, but I do know their service is only available up to 15000 feet from the telco's demarcation point (where their service is transmitted from). The further from the demarc point, the slower your service will run. They recieve their internet service to the demarc point through fiber, DS-3, or something simliar, and it's shared by some kind of router (not too sure what they use), and sent to the individual phone lines.

Cable Internet is good no matter how far from the cable office you live. The speeds remain the same whereever you are on the cable plant (everywhere cable feeds in your city). The service is fed into the cable company's office or headend (the place where the cable originates from) by fiber, DS-3, or some similar type feed (my cable company uses a 12mbps multi-link setup with about 8 t-1 lines). In our setup, the 8 t-1 lines go into a nice expensive router - then a 100mbps fast ethernet line goes into a switch to share that 12mbps service with our mail server, DNS server, and Broadband cable router (CMTS - short for Cable Modem Termination System). The CMTS has a RF network card that has about 7 connectors: 6 for upstream channels (what your cable modem transmits) and one for downstream (what your modem recieves). Those upstream channels are sent to individual parts of town (fiber nodes). The downstream line is broadcast all over town on one tv channel. Because of this type of configuration, many cable companies can provide internet service that far exceeds the speeds of DSL. My system could provide service up to 5mbps (or higher) if I had the bandwidth to the headend. Still yet, with 12mbps of service to the headend, I can still provide service on an average of 1mbps and up to a max of 2.5mbps to about 550 customers.

So, in summary, Cable Internet and DSL are NOT the same. They both have totally different technologies, and a totally different set of pros and cons. So when you call your local cable company looking for internet service, don't be asking for DSL. It's like going to Jeff Noble looking to buy a PC!

1 comment:

Mark W. said...

Being somewhat computer literate, I've never confused the two, but it was good to hear some of tech differences explained.

I think the overall key sentence was "AAARRRRGGGHHH!!!!!!" Don't we all hate those ignorant questions? :) Hope you're feeling some relief from this post!

Welcome!

HELLO EVERYBODY... I've now moved my blog to Wordpress.com . You'll need to change your bookmarks to point to http://tjscott.wordpress.com (for now!). I like the Wordpress format and way of doing things. It gives me more versatility. SEE YOU THERE!