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Cable vs DSL for reliability

JeepinEd

JeepinEd

Senior member
I'm looking to switch our office to a hosted phone system. I can't really afford a T1 line, so I'm trying to figure out which is more reliable. Cable or DSL? I'm looking at two similarly priced plans (6MB down/768KB up, with static IP). One from AT&T and one from Time Warner Cable.

Thanks.
 
The reliability is an ISP issue and Not Cable vs. DSL.

I find TWC Cable Internet service much more reliable than anything that ATT does.

In many markets ATT is not even the actual provider but rather leases DSL lines from someone else, in such cases their service is not just plain S**X, it is triple S**X


😎
 
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you want a t-1 dude. call cbeyond.

phone over cable is lame.

dsl is actually better when it works since they have less drops and packetmta is a lossy protocol.
 
I have successfully used cable internet for hosted VOIP's for several years now - no issues. The thing you have to keep in mind is VOIP is symmetrical - you're downloading just as much as you're uploading. You need to keep your upload bandwidth in mind - 768k will drain quick.

I would recommend that you take your maximum amount of simultaneous phone calls x 100kb/sec per call and use that to figure out how much upload you'll need. Also take into account normal internet usage as well. Definitely use a router that has upload QOS so that VOIP takes priority over any other traffic. I use this on my router and have yet to have a single issue. Call quality is superb. 768k for upload though is a bit low. I'd recommend min of 1mb upload, possibly 2mb if you can afford it.

As far as reliability - cable is a newer technology than DSL but as Jack pointed out - it's more of an ISP vs ISP as far as reliability.
 
Problem is he's saying he cant afford a T1 which is... $300+ per month. Cbeyond as far as I know only offers packages data+voice and it comes out to I think $400-500/month.

We just switched from cbeyond to time warner cable. Got a fiber optic line pulled directly to our server room and it's $500 a month for 5 / 5. Our cbeyond bill was around $1095 after taxes and fees for 2 t1 lines.

That and a single t1 in 2011 is just simply slow. I'm amazed that I can have 30Mbps / 30Mbps at home for $50 a month.

*nominates kevnich2 for best answer*
 
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For phones, especially if you are going fully hosted - you CANNOT operate without an SLA. Get a T-1. Get a T-1 and dedicate it to the phones if you have to.

Imagine this scenario: A jagoff in a backhoe cuts the cable line. It takes TWC 9 days to fix. In that 9 days - they don't provide service.

The effect on your company?

You cannot call extension to extension. You cannot receive incoming or make outgoing calls. The business is back to couriers, runners, and cell phones. I guarantee you get a pink slip when that happens.

Get a T-1. If the loop is cut you will be the first priority.
 
Problem is he's saying he cant afford a T1 which is... $300+ per month.
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Than stick with analog lines. Even those don't have the same SLA as a T1 would. It's the cost of doing business. 100kb is a good estimate both directions for voice.

I would rather walk away and not get the business than put in a phone system in a place that used a data connection without an SLA. It's not going to work and you will get screwed badly.
 
Sorry but with business cable internet - you do get an SLA and top priority with support. Our cable internet went out once at 1pm, we called in and there was a tech there at 1:45pm. Ended up running a dedicated line due to some issues and we were back up by 2:30pm. That's been typical of many cable, business class internet's I've seen.

I haven't seen any better with a T1 - just because you get a nice SLA, outages will happen. I've never had a T1 that was actually more reliable as far as uptime than cable internet.

My original suggestion still stands - get business class cable internet with enough speed to handle your needs. It will be cheaper than any T1 you can get, with as good or better reliability and definitely better speed.
 
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Reliability is a function of the ISP and the area. In my area, AT&T is very solid for DSL. We host many Hosted PBX systems on AT&T DSL and they work fine. I can't say that we've had more DSL outages than our Comcast customers have had cable outages.

The codec you use impacts it some as well. g.729 uses roughly 30k per call leg, whereas g.711 uses nearly 100k per call leg.
 
What people said already. Reliability depends on ISP, not on technology. It's all about how well ISP maintains its offices, equipment and last mile connection to your location. We've had both DSL and Cable and it depends on ISP and particular location. At current location last mile phone lines were so bad we couldn't get more than 1MBit from ATT with connection drops every half an hour. Cable is marginally better, but I have a tech coming out today for the third time in 18 months because Internet is down again. So... really you won't know until you try, and even if you do try the situation may change drastically in as little as a couple of months. If you can subscribe to both, test em out for two or so months and then drop the least reliable one.
 
JackMDS said:
The reliability is an ISP issue and Not Cable vs. DSL.
Click to expand...

Cable and DSL have different infrastructure, and as such have different weaknesses and strengths.

I worked for a cable modem provider in North Houston for 3 1/2 years.

Cable goes like this:

Headend - fiber trunk line - Node (converts light to RF) - split into 3 or 4 feeder lines - trunk amp (also called Distribution Amp (DA)) - Line Extender (LE) - tap - cable to house

All of this requires electricity - the node, trunk amp and feeder amps all have fuses and circuit boards. The power could go off 2 or 3 blocks over, and your cable will go down - due to there is no power for the amps. The fuses and circuit boards in the amps can be blown out by lightening strikes. An amp could be blown out 3 or 4 blocks over, and your internet is going down.

Cable also picks up outside interference more then DSL, due to the forward and reverse signals being broadcast on frequencies close to air TV broadcast and certain radio stations. A break in the shielding of the cable will let these signals into your line and cause internet problems.

Grounding of the house - if your house is not grounded properly, your TVs will try to go back through the cabel line to look for a ground. I have seen houses that were backfeeding 60 volts AC into the cable line - this interferes with the cable internet signal.

A lot of cable modem providers have not invested into fiber to the nodes. Instead of only being 3, 4 or 5 amps deep, their 20 or 30 amps deep. Every amp feeds noise into the line. Everytime a line extender or trunk amp bumps up the signal, they insert noise into the line, its just the nature of the beast and its just the way things work. The more amps a cable modem provider uses on their main line, the dirtier the signal.

A couple of VERY important question for anyone looking at cable modem:

Does the provider have fiber to neighborhoods? Or, are they using amps all the way from the headend? If your headend is 5 or 6 miles from your house, your going to get a lot of noise in the signal. I would say anything less then 4 amps is a good number.

After the signal is converted from fiber to copper, how many amps deep is their longest run?

When Time Warner rebuilt Port Arthur, Texas in 2000 - 2001, no run was longer then 3 amps deep. When Kingwood Texas rebuilt their cable system in the late 1990s, they went high tech for the time and no run was longer then 4 amps deep from the fiber.
 
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kevnich2 said:
Sorry but with business cable internet - you do get an SLA and top priority with support. Our cable internet went out once at 1pm, we called in and there was a tech there at 1:45pm. Ended up running a dedicated line due to some issues and we were back up by 2:30pm. That's been typical of many cable, business class internet's I've seen.

I haven't seen any better with a T1 - just because you get a nice SLA, outages will happen. I've never had a T1 that was actually more reliable as far as uptime than cable internet.

My original suggestion still stands - get business class cable internet with enough speed to handle your needs. It will be cheaper than any T1 you can get, with as good or better reliability and definitely better speed.
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You assume that you can convince the cable co that transient issues are their problem. A line cut is easy. So easy that I wouldn't even consider it a "big deal" because a) it is rare b) when it happen, it is really obvious because some guy is standing there with a perplexed look on their face while cut copper is all over the place.

I have used business cable with SLA's and the challenge is convincing them that 8000ms pings are not "normal" and getting them to actually role a truck etc. A T1 is simple. Slap a T-bird on there and every clock slip and error is recorded plain as day. Verify that the SLA actually covers minimum upload and download speeds, latency, jitter etc. I would be willing to bet that the cable SLA is a 'downtime' SLA not a latency / quality of line SLA. Jitter for example will kill faxing except for pure T.38 which is not 'cheap'.

Again this like above falls in to ISP vs the Tech. T1 / Cable / DSL all can be stable. If the ISP has issues (IE overloaded segment) you might be up a creek. Would I do it? Maybe for a small 3-5 line business. I would be 100% sure to have a "disconnected redirect" so calls are forwarded to a voicemail or can be forwarded to cell phones in case the service is down. I wouldn't stake a 100 person office on anything less than T1 / bonded T1
 
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Why not just get phone service from AT&T or verizon? They're happy to sell you business lines complete with digital phones and all the features you need. Even when you use VoIP you ALWAYS have a backup and that backup is normally a T1 or POTS lines. Business without phone service doesn't last very long and costs way too much money when they are down to cheap out on it.
 
Thanks for all the info.
The two services I'm currently looking at are "Business Class" services, which I would assume get a higher priority, should the line go down.
We are currently using an old analog phone system that goes through a router & converted to digital. The signal is going out through a fractional T1. Phone and net service is being provided by the same company. Because of the economy and shenanigans by our dear leaders here in California, we've taken a pretty good financial hit. Our phone system is on it's last legs, so I've been looking at hosted systems, which give you feature full IP phones, that can also be located in remote locations (my house). Not only would we have modern phones, but it would save about 40% on our phone bill.

One of the things I was considering was getting two lines from different providers (for redundancy) they would still be cheaper than a T1 and since the phones are IP based, I could run them on different networks. After reading all the comments, though, I'm thinking I may just need to come up with the $$ for a T1. I currently have three copper lines, which I will be keeping, in case of emergency.

No matter which way I go, I do plan to use a QOS router.
 
JeepinEd said:
Thanks for all the info.
The two services I'm currently looking at are "Business Class" services, which I would assume get a higher priority, should the line go down.
We are currently using an old analog phone system that goes through a router & converted to digital. The signal is going out through a fractional T1. Phone and net service is being provided by the same company. Because of the economy and shenanigans by our dear leaders here in California, we've taken a pretty good financial hit. Our phone system is on it's last legs, so I've been looking at hosted systems, which give you feature full IP phones, that can also be located in remote locations (my house). Not only would we have modern phones, but it would save about 40% on our phone bill.

One of the things I was considering was getting two lines from different providers (for redundancy) they would still be cheaper than a T1 and since the phones are IP based, I could run them on different networks. After reading all the comments, though, I'm thinking I may just need to come up with the $$ for a T1. I currently have three copper lines, which I will be keeping, in case of emergency.

No matter which way I go, I do plan to use a QOS router.
Click to expand...

Where in California are you located, who are you using for Hosted PBX, and how much have they quoted you?

I only ask because, depending on location, I may be able to get you a better deal on both T1 and Hosted PBX. PM me for details.
 
The two services I'm currently looking at are "Business Class" services, which I would assume get a higher priority, should the line go down.
Click to expand...

Don't assume anything. You either get an SLA or you don't. If not - look elsewhere. I really don't care what tech is used, its the power of the SLA that matters most. "business dsl" here in south FL does not include an SLA, and neither do they get priority. It took AT&T 3 days to fix a trunk problem that affected analog lines for about 700 businesses here a few weeks back.
 
I realized you have gotten various opinions on getting a T1/cable/DSL. However, your VoIP is as good as the internet pipe going into your business location.
As Drebo said, "Reliability is a function of the ISP and the area. In my area, AT&T is very solid for DSL. We host many Hosted PBX systems on AT&T DSL and they work fine. I can't say that we've had more DSL outages than our Comcast customers have had cable outages."

I have installed several VoIP telephony systems on DSL & cable none have experience problem with the Phone system. Only one had a problem with the isp (AT&T DSL) because of the amount of data usage had bog down their bandwidth; they had a 1.5M DSL pipeline; the fix that was put into place was to upgrade their service to 6M.

Your idea to to run both a DSL & cable is not bad one; with the system I install will allow for redundancy for failover should anything happens to the main VoIP isp pipeline. This system will allow you to take phone home and use it as if you were in your office environment. Just plug it into your home router and to a wall electrical outlet. This telephony system will allow you to drop the expensive T1 and allow you to get a business cable speed of 15 Megs for $89 here in the Detroit, MI area. This hosted VoIP is called Star2Star; it will give you the functionality and cost saving you need and want. Please email me & we will talk.
 
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