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Pri or SIP??? 5

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Newb2IT

IS-IT--Management
Oct 6, 2008
205
US
Hi guys...I do not have the much expertise with phone systems but I have the task of purchasing one...anyway we are a small business and after talking to the receptionist (by the way the new phone system will be at a NEW location)we basically never have more than 8 people making/receiving calls at the same time...so I guess 10 would be a safe number...I am planning on getting a hybrid phone system and I will have a 5MB data line coming from lightpath (with SLA) in which we can have SIP or PRI....I also plan on having a second "backup" data line from Cablevision (no SLA). MY question is should I go with PRI or SIP? I also want to be able to use the backup line for redundancy for the phones, so basically if the main data line from lightpath I want to use the backup data line as fail over so that we still have phones....Thanks alot!
 
ISDN is more reliable, and there are less people involved in delivering it (any problems can only be with the system or service provider). SIP is cheaper, but in my experience, goes wrong more often, and any problems could be with the telephone system, the internal network, the broadband provider or the SIP provider, and as such are often more difficult to trace and solve. I personally still prefer ISDN
 
If 8-10 is the maximum number of calls at one time, and you want reliability, you might want to look at plain old analog lines. Yes its old hat, but they are reliable, more so than circuits in most cases. However if you are planning on growth at the new location, you could start out with a partial T-1/PRI circuit and increase channels as needed. I agree with CatOnKeyboard, on the choice of circuits, just my personal preference.
 
Thanks guys I am assuming that by ISDN you mean PRI correct?
 
I'm in the UK, over here you can have PRI ISDN with a minimum of 8 channels, or you can have BRI ISDN, each circuit has 2 channels, I don't know about the States (if that is where you are)
 
Yes I am in the US and since I only need 10 people to be able to make/receive calls at the same time I don't understand dhy I need a PRI that has 23+1 channels...I thought it would be better to just get 10 SIP trunks?
 
You can get a FRAC T1 or PRI.

FRAC= fractional and add on as needed, might be a minimum.
 
Ironhorse thanks!....ok so if I get a FULL T1 and It want to frag half of it so that I get 12 channels...will I be able to use the other half for data? I also plan on having a few pots lines as backup
 
find out the acual cost for install, monthly, and usage local/long distance.
The setup cost for a PRI can cost 1K unless waived with long term contract. The cost per month may still be expensive even PRI is partial. PRI can be purchased with unlimited national outgoing.
POTS may end up costing more if there is alot of outbound and charges for local calls. Need to find out actual cost of POTS, PRI, or ip trunks. Need all the facts, a vendor should know and give best option for your company.
 
Did I misunderstand the connection? A quick review of LightPaths website tells me that they do not offer traditional PRI services.

You mentioned a 5mb data line with SIP or PRI. This tells me that Lightpath is using SIP all the way to your facility. They are only asking what type of hand off you would like. PRI or TDM hand offs allow Data Only (SIP) Carriers to accommodate older phone systems that lack SIP ability.

If I am correct, SIP reliability is not an issue because LightPath is using SIP not ISDN(PRI) from their NOC to your office. ISDN reliability comes from tried and true ISDN from the Telco's Central Office to your Location. The only exception might be if your phone system or SIP provider doesn't comply with SIP standards.

Lastly for 8 people SIP will be cheaper especially if you piggy back phone on your data connection. Just remember your back connection from Cablevision will not allow customers to call you. An outage from LightPath means not primary internet or incoming phones. You could configure the back data for outbound but you will need a separate SIP provider. Possible Cablevision but more likely an internet based SIP provider.

Confusing? Sorry

 
Unless you have nice new fibre in your area, then regardless of the technology, copper in the ground is always going to be a factor.

I think many ISDN telcos back off their trunks to SIP / VoIP anyway. Many SIP providers offer better call rates due to breakout agreements with other telcos.

BT here in the UK is moving all their voice to VoIP via their 21CN network. BT also sell SIP.

We use SIP in very busy taxi call centres (3-5K calls / day) and we have little to no complaints - all depends on how you deliver it. Most of it is on uncontended multi-line bonded SDSL connections, some on leased lines.

ACSS - SME
General Geek

CallUsOn.png


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Ironhorse.
"PRI= 23 B channels one D channel"
That's a T1, used mainly in USA and Japan

E1 maily Europe
30 Channnels + 2

then a mix and match such as DS3's etc all over the place.

Robert Wilensky:
We've all heard that a million monkeys banging on a million typewriters will eventually reproduce the entire works of Shakespeare. Now, thanks to the Internet, we know this is not true.

 
Sympology.

A T1 uses 24 channels of 64 K, 8 k per channel for the D channel carrying the info for that channel.

PRI 23 channels 64 k, the last channel carries all the info for all the channels.
 
IN FL BRIGHT HOUSE USES PRI OR SIP TRUNKS AS IF THEY ARE THE SAME WHAT IS BRIGHT HOUSE (CABLE CO ) SELLING T1 OR PRI ?
 
they are selling VOIP but if you want or need PRI they use a box to convert it so you can connect to your PBX.
 
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