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I do web development from home. I'm moving to a house on a road with not very many people. The only options for wired high speed internet are DSL or T1. The DSL tests out at 1Mb/s down, 512kb/s up. The T1 would be 1.544Mb/s both ways. I've been quoted $30/month per DSL line or $220/month per T1. We don't have 4G in the area yet.

I'm trying to decide between multiple DSL lines and a single T1. If I went with DSL I would likely get 4 lines and then use a Ciso RV016 router to load-balance them. I'm not sure of what my true throughput would be, and if it would be a hassle to configure it properly for different sites.

Any info would be GREATLY appreciated. Thanks.

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Is EoC available in your area? If you have 4 available pairs, EoC would be the best option. You get the low latency, synchronous upstream and downstream, and SLA of a T1, and you get the same redundancy as multiple DSL lines with the added benefit of bonding. – MaQleod Mar 21 '11 at 18:41
up vote 2 down vote accepted

T1s are better for latency and have a better SLA for repairs, though multiple load balanced DSL lines will provide for more bandwidth and greater redundancy (if a line goes down, your speed drops, but your connection stays up, so a few extra days for repair won't kill you, but an area outage would). You might be better off load balancing an ADSL2 and cable line, it will provide for better redundancy (if one network goes down, the other will remain up). Generally T1s are most useful for those who run servers because of the 1.5 up as well, the synchronous aspect is what is important. T1s also give the option of routed blocks as they are routed circuits and not bridged, so you can more easily manage multiple public IPs, which is again great if you run servers. Most people are fine with bridged circuits and they are much easier to configure for basic needs.

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1) it will provide greater aggregate bandwidth, but the fastest he'll be able to do any single download will still be 1Mbps. – peelman Mar 21 '11 at 17:43
2) Its 4 DSL links from the same phone company. Coming in over the same copper. From the same cabinet. From the same phone company. Explain to me again where the redundancy is? – peelman Mar 21 '11 at 17:44
Yes it can all be the same bay, shelf, card, etc, but it rarely is. Most of the time it will be a different card and often times a different shelf. Redundancy comes into play for the pairs on the street, should one suffer damage, the others will stay live. I mentioned that a network outage would destroy the redundancy. I specified that the best redundancy would be mixing cable and DSL. All of that was covered. Have you ever been in a CO and seen how pairs are distributed from the MDF through to the DSLAM? actual physical address has nothing to do with proximity of the pairs on the DSLAM. – MaQleod Mar 21 '11 at 18:29
You also fail to realize that a large percentage of COs have multiple DSLAMs and multiple trunks, so even if one entire trunk goes down, it may only affect one of the four circuits. – MaQleod Mar 21 '11 at 18:31
I used to work for a local phone company. You're putting a lot of assurances on the chance that the pairs will be connected that way, and the DSLAMs will be connected redundantly, and that the network is competently administered. Buying multiple links from the same provider and calling it "redundancy" is foolhardy at best. – peelman Mar 21 '11 at 18:40

Are multiple dsl lines really an option? Right now there's likely one existing phone line coming to your home. Additional dsl lines will require additional physical phone cables run to your home. This may cost a lot of money to set up or even just not be available. It's very possible someone at the phone company gave you a "per-dsl line" quote that simply ignored this issue.

If it is available, you will need software and a gateway that's capable of balancing these connections. One system I know of that can handle this is untangle. The core untangle software is free, but you'll need a three-nic (minimum) computer to run it on (one internal and one for each dsl line) and the wan balancer/wan failover plugins cost extra ($13.50/month total paid annually). If you have the skills, you can also do this for free on any linux system, but the setup is not trivial.

If it's not available, I just don't see $190/mo as worth it for an extra .5Mb down, 1Mb up for a home connection. In other words, there's not much that would make me choose the T1 option, ever. But this is a personal choice.

One final thing to look into is a residential wireless service. These services are generally located in towns where better dsl, cable, or business fiber is available, but there are surrounding rural areas such as yours where none of the above are available, or are much harder to get. They will install wireless bridge connections that link from your home to their office, at a range of up to 25 miles depending on the equipment available and terrain characteristics.

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They just ran an extra line, so there are two lines to the house now. It costs about $200 per line. I have line of sight to a wireless tower, they charge $45/month for 1Mb/s down, 512kb/s up. I can probably get a faster connection if I talk with them, they are a local company. – Cyrcle Mar 21 '11 at 17:38
With that information, I'd probably go the dual-dsl+untangle router. They're a little pricey, but you can get pre-built untangle appliances that are very nice here:… (no affilliation) – Joel Coehoorn Mar 21 '11 at 18:00
I'm planning on using the Cisco RV016, which supports up to 7 WANs and runs around $400 – Cyrcle Mar 21 '11 at 20:03

To expand on the other already good answers here: 4x 1Mbps DLS lines != 4Mbps of throughput, it doesn't matter what load balancer you put in place. Unless the ISP is in the loop and is bonding the links together on their end to act as a single trunk, any single download stream is going to be limited to a single DSL line and capped at 1Mbps; you can't load balance an single incoming stream, say a large file from a web server, across multiple incoming connections. You can send traffic out multiple connections with the same destination, and you can receive in total 4 independent 1Mbps streams.

Unless the phone company is bonding the links on their end, you're going to have 4 IP addresses, which means 4 different point to point connections capped at 1Mbps. Multiple connections and Load balancing are good when there are multiple end points on each end of a connection, but your point-to-point speeds are limited by the fastest/slowest single link. When its 1-to-many (you-to-AllOfTheInternet) its not really doing you any favors except redundancy (though if all the links are from the same provider if one goes down, chances are so are all the rest, so nix that idea).

Also, $220/mo for a T1? for 1.5Mbps? Really? SLA or not, that is an outrageous amount of your income being flushed away into an overpriced business expense, especially when you're willing to take DSL lines (regardless of quantity or quality) as an alternative.

And just to top this off, it may sound prude-ish, but for future reference: When your job / way-of-life depends on having quality internet, that should probably be more of a factor in your home purchasing/renting decisions.

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The house is worth extra expenses to get a decent internet connection. – Cyrcle Mar 21 '11 at 19:03
Oh how many times I've heard that. Hopefully civilization will reach out to you in the next few years in the form of decent wireless or some large scale fiber deployment... – peelman Mar 21 '11 at 20:04

DSL certainly gives you a lot more bandwidth for your buck, but keep in mind the three magic letters that you get along with the T1 line: SLA. "Service Level Agreement". A contract guaranteeing that your T1 will be up at least some specified portion of the time. With DSL, you can't get that and, even if you've got the wiring available for multiple DSL lines (Two? Maybe - the house may have been previously wired for a second voice line. Four? Highly unlikely.), they're going to be running through the same areas and likely the same conduits, so anything that takes one down will have a good chance of taking them all down.

If you need high speed and low cost, DSL's the way to go. If you need absolute reliability and uptime guarantees, then you need the T1.

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If you look closely at SLAs, they don't technically guarantee uptime, there really is no way a ISP can guarantee that realistically. The SLA just provides greater recourse to escalate should the need arise and a better credit scheme when deadlines are not upheld. – MaQleod Mar 21 '11 at 18:54
True, fair enough. – Dave Sherohman Mar 22 '11 at 8:05

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