I used to work for a telecom, so I know some of the benefits. But this was about 6 years ago. We monitored our customers T1’s and their contract specified, if I remember correctly, a 4 hour response time in event of an outage. A T1 gives you 24 channels at 64K for a total bandwidth of 1.5MBPS. Actually it was 23 channels and 1 monitoring channel on a PRI. (my specifics may be slightly off).
The customer had the option to use all 24 channels for data or they could use say 12 channels for data and 12 for voice. But you’re still only talking a max bandwidth 1.5 MBPS. And in that case, 512 KBPS for a small business seems awfully slow.
I currently get 16 MBPS over my home DSL. And while the price of T1’s have come down considerably over the past 10 years, they are still kind of expensive.
What is the selling point for T1’s now? Is it just the flexibility and the monitoring? Even when I worked in the industry, we were responsible for it up to the demarc (where it reaches a channel bank on the customers property). From that point I never had a good understanding of the ways an IT dept. may choose to use this internally.
Perhaps their bandwidth is dedicated? The telecom can say you’ll get 16 MBPS but if everyone on their system is active as possible you won’t get that and could possibly lose service. Plus, some companies will drop you or charge you more if you are constantly pegging your bandwidth.
On the other hand, if a T1 has a “guaranteed” throughput, it would explain the price discrepancy. They won’t be charged extra for maximizing their bandwidth usage and it won’t drop below what they are paying for as a design parameter (occasional outages I’m not sure about, though.)
Which isn’t to say that a T1 is worth it even if I what I said was true. I don’t know how much they cost these days.
I have some friends who still work at my old company. $500-$1200 per month, depending on what’s required to run the line to your location and I presume the specifics of your maintenance contract.
Your DSL (as well as cable) is most likely asynchronous, meaning your download speed is higher than your upload speed. Most businesses need synchronous, in order to provide decent upload speed to accommodate mail, web, and ftp servers. T1 is always synchronous, 1.5 up 1.5 down. There is also SLAs (service level agreement) built into most T1 circuits that specify the type of reliability your company or the phone company was providing (4 hour downtime max, priority technical support, managed routers etc…) T1’s can be bonded to create larger pipes as well. It certainly was the de-facto standard for high speed connectivity for too many years.
My personal experience show that T1’s for internet are finally on the way out, being replaced by Ethernet or fiber. T3 (48Mbs) is still available but expensive. Currently in our area, an internet T1 typical runs around $300 a month, a phone PRI T1 about $200 a month + per minute usage charges. It keeps dropping thanks to competition with fiber/Ethernet.
Many T1s are private circuits for private networks. They are widely used by public safety entities for voice and data backhaul for dispatch and mobile data terminal operations.
T1s are older technology, more well-understood, more stable, and the equipment is largely paid for. Need a little more bandwidth? Well, you probably have another port on your line card and can multiplex.
If you really, really need the extra bandwidth to where mutiplexed T1s or whatever become unwieldy, metro ethernet or whatever may be what you have to go to, but that will almost certainly involve changing out a lot of infrastructure, retraining, and some stability loss, particularly as people are still getting used to the new stuff.
The company I work for has many sites scattered across Northern California, Nevada, and Oregon. Most of these locations are connected to the corporate WAN via T1 lines. They are relatively inexpensive, and 1.5 MB of dedicated bandwidth is really plenty for a small sized office. In some of our slightly larger offices we bundle two (or more) T1’s into a single virtual circuit for additional bandwidth.
I’d give you a detailed technical rundown, but I’m a server guy, not a network guy.
How can you order Ethernet as a replacement for a T1 circuit? Does that mean that the phone company runs a 100MB Ethernet cable from the central office to your building? And what kind of speeds can you get with a fiber connection, and at what cost?
Reliability and monitoring. T1s seem to be run by people in the telco rather than the ISP mindset, and that tends to make for faster repairs and fewer outages. Also, they’re pretty much ubiquitous, and the technology is very well understood in most locales and in most companies’ networking teams.
DSL, in contrast, is typically used for last-mile access only, with the other end of the link terminated in ATM - so you’ll at least need the knowledge to run two different technologies. And ATM has a pretty steep learning curve.
Of course, if all you need is Internet access rather than site-site, DSL is dirt cheap.
It depends. We’ve had 100 Mb Metro Ethernet in the LA area - I’d have to look up the prices, but it wasn’t cheap - based on fiber connections running out to a Canoga-Perkins switch in each locale, and we just received data across a 100 Mb UTP link (dot1q tagged, IIRC).
Our MPLS network is migrating from T1/E1 to Ethernet as access technology as the bandwidth requirements are going up, but just a few years back, last-mile Ethernet was prohibitively expensive in a lot of places. Still is, in South America at least.
In our case, we have a fiber node that terminates in our server room. ATT plugged one side into a fiber to Ethernet switch and I take a CAT6 to my router. I can get up to 1Gb with a simple call to my provider. Currently I’m paying for a 20Mb circuit, up and down.
Various posters have hit on the primary benefits of T1 over DSL. You pay much more for the service guarantees. T1 bandwidth is a guaranteed 1.5Mbps and line service usually comes with repair SLAs, overall uptime SLAs, and provisions if the SLAs are violated by the service provider (usually some % of that month’s service charge is refunded to you). In contrast, DSL is typically best-effort service, although some business DSL now comes with SLA agreements. DSL is distance-sensitive and bandwidth is usually not guaranteed beyond certain minimums. Other options such as Ethernet are possibilities, but they can get very pricey depending on the existing infrastructure in the area.
One alternative to DSL is internet access from the cable company, which they seem to be pushing a lot where I live. I have no idea of the SLA they offer.
