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cramer
Premium
join:2007-04-10
Raleigh, NC
kudos:9
reply to BiggA

Re: Analog Voice Gateways

Tell it to the Vonage crowd. Despite the thing being upstream of their router where it can "apply QoS", people still have call quality issues if the line is moderately used. VoIP within a company LAN, you'd think that wouldn't be a problem, but it can, and does, happen.

In the end, there are as any reasons to keep voice and data as isolated from each other as possible, as there are not to. The best way to learn is having them sneak up and bite you on the a**.

(I see it myself with VoIP over IPSec. Back when TWC was 384k up, you best not do anything while using the phone. Now at 1M up, you just have to be careful not to push it while on the phone. Unless you like a stuttering phone.)

BiggA

join:2005-11-23
EARTH
On a 100mbit line, it's unlikely to happen. I don't seem to have issues with my AT&T Microcell when I'm hitting the 'net hard, probably because I have the Microcell god-esque QoS priority in the router.

I do have general upload jamming issues though, so I've cut my torrents, backup, and Google Music down to 1mbps each, but if two or three of them kick on at the same time, or with Dropbox, then everything kind of grinds to a halt on the web browsing side of things.


sk1939
Premium
join:2010-10-23
Mclean, VA
kudos:10
Reviews:
·T-Mobile US
·Verizon FiOS

1 edit
It's not a question of bandwidth to the internet for many of these campuses, it has to do with QoS and congestion on the internal network. Additionally, the number of lines many of these enterprises have would take a heavy toll in bandwidth (they number in the hundreds, if not thousands). Remember that the average VoIP call takes about 130kbps of bandwidth (counting overhead), or about 80 lines with 10mbps of bandwidth.

I'll give my two cents having designed a network for a higher education campus.

Due to security issues, and the existence of an original PBX, only some lines were replaced with VoIP, notably offices and labs. Classrooms and Emergency phones remained on the PBX due to technology limitations and cost. Each of the VoIP phones needed a new line to be run for every phone since the existing wiring was based off of Cat 3. The network was designed so that voice traffic was independent of the data network to help with latency, security, and network congestion issues. Likewise, the IP cameras on campus are also on an entirely separate network for security reasons. This particular organization uses PoE for the switches at quite an expense, and runs an Avanya PBX system for VoIP, and a Siemens PBX for POTS.

The POTS infrastructure was not transitioned using FXS devices for the simple reason that the existing PBX was in place, and for emergency situations should the core routers fail, the campus would still be able to reach out through conventional means.

The problem with VoIP is that it requires you to have a stable, consistent, and good quality internet connection with little loss. Should your internet connection fail at any time, then you have serious issues about not being able to contact the outside world. "Use your cell phones" is not an acceptable answer to these enterprises.

BiggA

join:2005-11-23
EARTH
Why are the bitrates cranked up so high? Cell phones are something like 10kbps.

"Use your cell phones" should be an OK answer, as they will always work. Of course, you could always have a backup internet connection in case one fails...


sk1939
Premium
join:2010-10-23
Mclean, VA
kudos:10
Reviews:
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·Verizon FiOS

1 recommendation

Standard VoIP bitrates (like G.711) are at least 40kbps, and many are 50 or 64 plus packet overhead. These are land lines that have to be clear to the other end. There's a reason Verizon ran those "can you hear me now?" ads, since 10kbps is terrible quality considering AM radio is 24kbps.

It will never be acceptable to Fortune 1000 companies, especially when people/clients go to call them. Additionally, if you add that much cell traffic, the towers can be overloaded, not to mention the cost of minutes. It just has to work, because that's what you are paid to do. Yes, you always have a backup but even backups fail.

BiggA

join:2005-11-23
EARTH
Regular phone systems can bite the dust too, it's not like any of this stuff is super reliable. At least VOIP you could have multiple bandwidth providers as redundancy, as opposed to one phone company where if something blows up.

It's hard to find hard data, but AFAIK, the highest bitrate WCDMA can handle is 23kbps, and WCDMA on the iPhone is higher than landline quality. Admittedly, there's probably a lot of processing going on in the iPhone, but it is able to pull it off.

Not sure if I've ever used a VOIP system, but a good cell phone connection (like AT&T 3G on the iPhone 4S) definitely sounds better than a copper landline. Again, might be processing and massaging, since Apple spends a LOT of time and money on every detail of the thing.


sk1939
Premium
join:2010-10-23
Mclean, VA
kudos:10
Reviews:
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POTS is still more reliable than cell phone service that's for sure. The problem with redundancy I already stated before. I've also previously stated the reason companies keep POTS, mostly due to security and cost.

Higher than land line quality perhaps, but not better than VoIP. Additionally quality is not important in classrooms and for emergencies.

That's subjective and depends on the quality of the line, the distance, the age of the line, the phone handset, and variety of other factors.

BiggA

join:2005-11-23
EARTH
OK, maybe VOIP can beat a cell phone, I know Skype has some of the best quality that you'll get on any sort of "phone". Land lines aren't that great, however, as they are analog and have basically no processing power at the end of the line. The best calls that I have are AT&T to AT&T on the cell phone side...

BiggA

join:2005-11-23
EARTH
reply to sk1939
Also, why would you have phones in the classrooms? There is no reason to have them, since people are moving in and out of them all the time. My university has the same thing, and it's just a waste of money. As are dorm phone lines, since no one uses them. They should just rip the whole system out.


sk1939
Premium
join:2010-10-23
Mclean, VA
kudos:10
Reviews:
·T-Mobile US
·Verizon FiOS
The phones are there for emergencies, and for the instructor to call for services such as Plant Ops, Security, A/V, etc.

Dorm phones are a legacy from the time before cell phones. Why would you rip out a perfectly functional system that's in place?

BiggA

join:2005-11-23
EARTH
I've literally seen professors need to make phone calls, they don't even notice they are there. They just pick up their cell phones anyways. If they put that money towards getting better in-building cell coverage, we would all benefit.

Well, maybe not rip out, but just unplug and let it go dead. There's no reason to keep paying every month to support a system that no one uses.


Edrick
I aspire to tell the story of a lifetime
Premium
join:2004-09-11
Woburn, MA
I'm guessing you're still in college? I myself only just recently graduated two years ago. However plenty of times in real world situations campuses, companies, government etc... require things to be secured, segmented, installed and maintained even if you don't view them as needed. From the world experience I've had so far what sk1939 has said is completely accurate.

Also an example public schools are required to have some type of hardwire communication in the classroom for the teachers to call to the office. I've seen the hardwired phones used many many times in the two universities I've attended to contact plant staff, call for an emergency or other on campus calls. Why have the teacher be required to save 20 phone numbers into their cell phone when they can just use the phone system in the school and call a local extension.
--
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Independent Film & Broadcast Producer
»edricksmith.com

kc8jwt

join:2005-10-27
Syracuse, OH
Edrick is right. I work in a public school and we have a copper plant for phone and our network plants.

Our phone system is a traditional PBX with a VoIP card to call other districts in our consortium. In each classroom we are required to maintain a phone jack, two network drops, and a CATV jack. If we don't maintain them, we can not get money from a state grant designed to maintain them.

The problem we have with it is that AT&T put the jacks in illogical locations such as the back of the room when the teacher's desk is at the front of the room.

BiggA

join:2005-11-23
EARTH
reply to Edrick
I'm talking higher ed. K-12 makes sense, as the teachers need to be able to communicate with each other, support staff, and the office.

In higher ed, no one would know the numbers anyways unless they are printed somewhere (just as easy to dial on cell), or they Google them and dial them, which would be on their own smartphone anyways.


Edrick
I aspire to tell the story of a lifetime
Premium
join:2004-09-11
Woburn, MA

1 recommendation

said by BiggA:

I'm talking higher ed. K-12 makes sense, as the teachers need to be able to communicate with each other, support staff, and the office.

In higher ed, no one would know the numbers anyways unless they are printed somewhere (just as easy to dial on cell), or they Google them and dial them, which would be on their own smartphone anyways.

It's still far easier to have hardwire, I know plenty of spaces on both campuses where we didn't have cell service or the teacher didn't have a phone, perhaps the computer network was down and they cant get on the intranet. They can pickup and hit 0 be connected to the switchboard.

Alls I'm saying is hardwire is far from dead and will be around for quite sometime.
--
Edrick Smith
Independent Film & Broadcast Producer
»edricksmith.com

BiggA

join:2005-11-23
EARTH
No one uses them. No one wants them. If there's not good cell service, then that's a legitimate issue that needs to be dealt with, either through repeaters or partnering with AT&T and Verizon to come in and install sites to cover deep inside buildings.


Edrick
I aspire to tell the story of a lifetime
Premium
join:2004-09-11
Woburn, MA

1 recommendation

said by BiggA:

No one uses them. No one wants them. If there's not good cell service, then that's a legitimate issue that needs to be dealt with, either through repeaters or partnering with AT&T and Verizon to come in and install sites to cover deep inside buildings.

Well with an attitude like that I don't know how well you'll do in the industry. Cause lots of people use them and lots of people still want them. This installation posted by the OP is a prime example, if no one used them or wanted them why would the university spend all the money?

Cell service is not a valid replacement, wether it be local, state or government requirements or just the institutions requirement. A cell network goes down, especially during emergencies.

What practical experiences do you have where you can make a statement that no one uses it no one wants it other than your personal experience at your campus?

Just like Antenna you might say who the hell would use antenna for TV, lots of people still do.
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Edrick Smith
Independent Film & Broadcast Producer
»edricksmith.com

kc8jwt

join:2005-10-27
Syracuse, OH
reply to BiggA
It makes sense to run the cable for everything when your running the cable. It's pain all the way around when you have to go back in and run new cable later. It's cheaper to run all of the cable at once than to run it later.

We're finding that out now as we had network drops out of spec when AT&T wired our building 12 years ago. I had to have fiber run and re-deploy a switch to take care of these issues. Just finished lighting it up yesterday.

Truthfully, I would much rather have a phone in the room. It's a safety issue more than anything. And with VoIP some of the endpoints can be moved from room to room and the extension would follow. You can tie the extension to the MAC address to the handset.

BiggA

join:2005-11-23
EARTH
kc8jwt, That's absolutely true. Running more cable is always better. That doesn't mean that you need to actually activate it all right off the bat.

No one wants POTS lines that no one uses. Safety? In higher ed, no one even realized the phones are there, or knows if they work or not. Which am I going to use in an emergency? Some wall phone that might not work and no one has used in years, or an AT&T or Verizon smartphone that is a known quantity? I'm picking up my iPhone, thank you very much. I know the call will go through, unlike some crumbly POTS system. Plus, if there are more than a couple of people in a room, there's the built in redundancy of having two carriers, in case one just happened to be suffering an outage that day. That, and if the electricity goes out, who knows what's working and what's not, it's very random as to what's on generators or batteries, but you know AT&T and Verizon have generators that are going to keep things juiced up.


Edrick
I aspire to tell the story of a lifetime
Premium
join:2004-09-11
Woburn, MA

1 recommendation

said by BiggA:

kc8jwt, That's absolutely true. Running more cable is always better. That doesn't mean that you need to actually activate it all right off the bat.

No one wants POTS lines that no one uses. Safety? In higher ed, no one even realized the phones are there, or knows if they work or not. Which am I going to use in an emergency? Some wall phone that might not work and no one has used in years, or an AT&T or Verizon smartphone that is a known quantity? I'm picking up my iPhone, thank you very much. I know the call will go through, unlike some crumbly POTS system. Plus, if there are more than a couple of people in a room, there's the built in redundancy of having two carriers, in case one just happened to be suffering an outage that day. That, and if the electricity goes out, who knows what's working and what's not, it's very random as to what's on generators or batteries, but you know AT&T and Verizon have generators that are going to keep things juiced up.

Without looking what is your campus safety phone number? I've never had an issue with a wired phone system inside a building working or not. Anywho this discussion seems to be going in a circle, everyones got their own opinion I'm just saying when a client asks you to install a system they're going to look at you funny when you go. Shit man what you taking about use that cell phone you don't need no stinkin phone system.
--
Edrick Smith
Independent Film & Broadcast Producer
»edricksmith.com


DarkLogix
Texan and Proud
Premium
join:2008-10-23
Baytown, TX
kudos:3
I'd go with over wire the place for easy expantion

then put phones in all the classrooms as yes if the place has a safty dept then it'll come up if they're worth hiring.

I'd also add wireless AP's and have some wifi cisco phones available


sk1939
Premium
join:2010-10-23
Mclean, VA
kudos:10
Reviews:
·T-Mobile US
·Verizon FiOS
reply to BiggA
Universities require staff members to memorize important numbers for things like Plant Ops and Security, it's part of annual Prof. Development training. Additionally, many of these numbers are listed in the speed dial of the POTS phones.

POTS lines in a well maintained and professional setting will always work. Cellphones are spotty at best, even the iPhone. Installing cell phone repeaters is a costly, and frankly ridiculous proposal since cellphone service is the first to go in an emergency, and rather than dialing an extension (4154), you have to dial a whole number (1-815-518-4154).

BiggA

join:2005-11-23
EARTH
That's stupid, because you can just google all the numbers, or have students in the class google them. The numbers for the computer people are on the desktop background I think. I've seen professors call them a few times, always on personal cell phones.

Cell phone repeaters are needed for normal cellular use, not just emergencies.

I have no clue what any of the campus numbers are. If there's a real emergency, we have 911, and that would get routed back to our police. If not, I can google any number that I would ever need in under 30 seconds, and click on it on my iPhone.

Cell phones are last to go, as they have some of their own backup power. Anything wire based is really hit or miss.

TheMG
Premium
join:2007-09-04
Canada
kudos:3
Reviews:
·NorthWest Tel
reply to BiggA
said by BiggA:

I have no clue what any of the campus numbers are. If there's a real emergency, we have 911, and that would get routed back to our police. If not, I can google any number that I would ever need in under 30 seconds, and click on it on my iPhone.

You call 911 directly, they have to figure out where on campus you are located, which might not always be so obvious.

If you use the landline phone and call security, they will usually be able to provide assistance until the emergency services arrive, as well as guide the emergency services to the location of the incident.

So which is better?


alphapointe
Don't Touch Me
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join:2002-02-10
Columbia, MO
kudos:2
Reviews:
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reply to BiggA
said by BiggA:

Cell phones are last to go, as they have some of their own backup power. Anything wire based is really hit or miss.

WOW! You obviously don't work in the real world. Have you even seen an "emergency"? It doesn't take long to overload and crash a cell site. I'll take wireline over radio any day of the week, and I'm a ham radio operator. It takes a LOT to crash a properly maintained POTS system. At the hospital where I work, we've lost the PRI's for our PBX exactly once in the 10 years I've worked there, and that was for about 20 minutes... the cellular sites that serve the hospital crash or are overloaded on a regular basis. I'd wager most (crybaby Iphone loving) college students don't even know HOW to use a POTS phone...

And this topic has gotten so far off topic... I, for one, would love to see the telco side of this gear (which is quite sexy, I might add... I want one of those weatherproof cabinets!)
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TheMG
Premium
join:2007-09-04
Canada
kudos:3
Reviews:
·NorthWest Tel

1 edit
reply to BiggA
said by BiggA:

Cell phones are last to go, as they have some of their own backup power.

Many cell sites only have battery backup, no generator. After a few hours, they go dead.

In fact, I'd be ready to bet that most cell sites in an urban area do not have generators. I've seen generators installed mostly in remote areas where prolonged power outages are more likely.

Oh, and there's also the fact that landlines are considered an essential utility. Cell phones on the other hand, are not. In a big emergency or natural disaster, priority will likely be given to getting the landlines back up and running, before getting cell sites back up.

BiggA

join:2005-11-23
EARTH
reply to TheMG
I could tell them where I am. By building name. Same as by landline.

The bigger cell sites are diesel backed-up. We have two cell sites, the bigger and taller one is definitely diesel backed up. Most of the sites in CT are diesel backed up, for AT&T and Verizon. T-Mobile and Sprint don't seem to care, and they don't build shelters for the gear, just little outdoor cabinets.

I'm pretty sure the cell carriers put a lot of effort into keeping their networks running. Well, AT&T and Verizon that is.

Hahausuck
Premium
join:2003-12-14
kudos:2
Cabinet based sites can be batteried and genset powered too.

But if you are building a cabinet-only site chances are you are a cheap ass, not willing to drop in an LP or diesel fed genset.

So therefore we go back to your statement.
--
"Saying something in another language that you don't think the other person understands is just saying that you're a pussy and are too afraid to say it in English." --Harddrive