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Hosted VOIP with different ISP

I have a client who has me looking into Hosted VOIP solutions.  They have four sites, about 15 phones total, and nothing too unusual in their requirements.

My concern has to do with getting internet service from an internet provider that is not the same company that provides the Hosted VOIP.  More specifically, the ISPs with whom I have spoken can't guarantee QoS all of the way to the Host site.

The Host companies tell me that it usually works just fine.  They will do tests from our site to theirs for a few days or longer to ensure that communication integrity is reasonable to expect.

The big concern that I have is that there is no assurance that there won't be a problem with traffic prioritization in the future.  The ISP will take the stand that they never guaranteed it in the first place and the Host vendor will say that there is nothing they can do about it.

I will ensure that all of the internal switches and routers and such will support QoS.

One solution for this is to have the ISP do the VOIP Hosting.  We are getting a quote for that, but I am expecting a substantial price difference.

Should I have these concerns?  Is anyone experiencing these problems?
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Hi - you should be looking at the leaders in hosted VoIP like 8x8 or ring central.  For 15 phones at 4 sites, coax cable is your best choice.  T1's are expensive and slow, and IMO less reliable than coax.  Ethernet (fibre) is best but probably overkill for the number of users.

I have 500+ users now on ethernet, ethernet over copper, bonded T's and coax with no issues.
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@Jon Giese:
We are looking at fiber as it is less expensive than the other reasonable options.

My concern was not about raw data speed, but about prioritization.  Do you have any assurance in your installation that your ISP will maintain QoS over the connection to whomever is hosting your VOIP?

No matter how good the Hosted VOIP provider is, I am concerned about issues that will occur if/when packets are delayed or out of order.  This would be out of their control.
No Hosted VOIP solution will guarantee QoS when they are not the ISP host or partner.  Technically it is no different than a traditional analog provider, they guarantee their service up to the demarcation point.  With a traditional analog line that point is usually the electrical room, in VOIPs case that point is technically where their owned/leased/partner network ends.
"No Hosted VOIP....":  this is as I have understood it.

Which gets back to my original issue.  What is the client to do if there are voice quality issues that crop up in the future that are related to QoS not being supported by the ISP?  I see no solution to that under this scenario.

How long have you had your 500+ users on Hosted VOIP with a different ISP?  Have you never had voice quality issues related to the lack of QoS?
Hi - traffic shaping is done on your security appliance - we use cisco meraki.  So the customer is controlling the QoS on the circuit to the ISP.

The service provider will also have SLA's for latency and packet loss.

We do extensive testing on the customer network BEFORE selling them a hosted phone solution.  There can be other issues besides the internet connection.

We only started looking at hosted solutions once they started to support enterprise business, which has been their focus over the last 3 years.  One customer is 260 phones at 25 locations with comcast, twc, acc, at&t, pentel, and consolidated as their internet providers.  We looked at doing a MPLS network but it was 4 times the cost and MUCH slower (T1 vs cable).  The meraki's create the mesh network.  The 2 larger divisions have fibre with coax failover.  The showroom locations use verizon air cards for failover.
There is no easy solution if you get voice issues in the future.  Both sides will point to each other for faults until you prove them wrong.  Trust me on this, the ISP salesman will always say that we'll support everything and be proactive with issues, but when you actually deal with the ISP's NOC, it will be a very different story.  I've been in IT a long time and it's the same results from small to enterprise level ISPs.

We've had issues with the lack of QoS and that is why we are moving over to MPLS where our ISP can guarantee call quality all the way.  It's the concept of "one throat to choke" lol.  The only thing you can do is have two VOIP hosted providers using the same ISP.  That way you can tell either the ISP that there is something wrong with the VOIP if both VOIP providers are having issues or the VOIP provider if only one VOIP provider is having issues.  Not the greatest solution....

MPLS may be slower but as you are aware, it is not the speed but the latency that counts.  Any ISP can guarantee latency but read the fine print, it is usually only latency to a certain point (usually their gateway).  Once it goes to the internet, no one can guarantee what happens.

To put it into an easier concept, you have your car parked in your garage.  You can control how easy and smooth the driveway and garage (ie, your internal network) is.  Perhaps you are in a gated community that maintains the neighbourhood roads (ie, the ISP) going to the public main road (ie the internet).  However, once you are on the public road, you have no guarantee on how much traffic and the conditions of the roads will be.
SIP + MPLS still has lots of pain points.

 - T1's are really slow, really expensive and the managed router they provide will not failover to coax or cellular if the T1 goes down.  They tend to go down more often than coax because of the older infrastructure and the ILEC's don't place a priority on them like they do for ethernet
 - You need a voice gateway at each office for 911 = more expense
 - Is the ISP good at SIP?  Do they have geo redundant connections to the PSTN?
 - T1 goes down or has issues, is it the ILEC or CLEC?  It's comical watching the CLEC try to blame the ILEC and have them dispatch.

I would not tolerate voice quality issues either so I understand your need to change SIP providers, but I wonder if that is where the issue lies?  You should be able to run a comprehensive network test back to the SIP provider and see where the hangup is.  And if the SIP provider is good they'll provide you with call quality logs.
15 phones ? that shouldn't really be a problem! The amount of phones is not big and depending how many sim calls those 15 will apply it will vary if QoS is required unless the line is shared with DATA too not just VoIP.

I have deployed a SIP solution for a customer at 3 sites, they are using VPN in their 3 sites and one VoIP gateway on the HQ location. everything has been working perfectly with Fiber connection without any issue.

Rarely they would have a problem with the gateway but it's not related to the connection, mostly it's SIP trunk related from the carrier side.

I think you shouldn't really have these concerns esp when we are only talking about 15 phones.
As I understand the technology, the quantity of phones is not the issue; the uncontrolled traffic between the site and the VOIP Host is.  I am not worried about overloading our LAN or our internet connection to the ISP.  I'm concerned about what happens after it hits the ISP's router.

As I understand it, there are the following steps along the way:
1)  Phone to our router (through our switches)
2)  Our router to our default gateway (ISP router)
3)  ISP router to the non-ISP part of the internet (through ISP's infrastructure)
4)  Unknown number of hops on the internet to the VOIP Host router
5)  VOIP Host router to the Host computer (through whatever infrastructure they have)

I am not concerned about 1, 2, or 5; we can control those.  Given that we can't control 3 and 4 and that the bandwidth is shared with other (unknown) users, that is where I am concerned about issues.  There is no QoS assured nor any other latency guarantees in either case.  I've seen how inconsistent latency can be with data traffic and expect that when this occurs, voice quality will have noticeable problems.

We could have a single phone, but if there is saturation (even short term) in 3 or 4, then the packets will get delayed or dropped.

I recognize that many use this technology and don't have problems.  My presumption is that those have been fortunate, but can't count on this indefinitely.  I have also spoken with some who have had problems on systems that worked fine for months.  These problems seemed to relate not to configuration problems or hardware issues but to the inconsistent and unreliable nature of the general part of the internet.

My hope here was to get some technical insight on why I shouldn't be concerned about what seems to be a clear potential issue that would not have a resolution.
Sorry, now I understand better! in this scenario you definitely need QoS and also both ISPs should talk to each other with the gateways that they will place on each site in order to do the normalization, signaling...etc

but in my opinion I think this scenario would cost you a higher cost than regular one! why don't you go with cloud PBX ? some cloud services provide solutions that suits your needs competitive prices.
"My hope here was to get some technical insight on why I shouldn't be concerned about what seems to be a clear potential issue that would not have a resolution."

You answered your own question.  There is no resolution to a very real potential issue other than utilizing a cloud pbx that is either partnered, owned or the same company as the isp that can guarantee service from your infrastructure to the phone network.  Lots of people don't have issues but there is no guarantee that yours won't.

Ignore what others say about fiber or cable being best, they will never have control over the middle internet part unless they also provide the pbx solution.
"You answered your own question."
I posted the question thinking that I had the answer, but needed confirmation, which I received here.  It seemed like an obvious problem without resolution.  My only reason for uncertainty was that these hosted services exist and I didn't see how they could be successful and without problems.

Thanks to all for the input.  I can advise the client better now.
re: "cloud PBX"
How does that differ from the Hosted VOIP that I have been discussing?
It will differ in terms of cost because you will first get one offer from a single host not several ISPs. also you said that the ISPs with whom you spoken can't guarantee QoS all of the way to the Host site.

This very statement wouldn't really encourage me to use a hosted service from an ISP which can't guarantee the quality of its own service.

Check Intermedia's technical white paper about the QoS for hosted PBX too.
I think we are having terminology problems here as I suspect we are on the same track.

I was asking about using Hosted VOIP where the ISP that provides internet service is NOT the same company as the one doing the hosting.  My experience has been that when one is only getting data (vs. VOIP) service through an ISP then there is no assurance that QoS is maintained within the ISP's network (Step 3 above).  In any case, even if the ISP will guarantee QoS within their network, it can't guarantee QoS to the Hosted VOIP site when it is not their site unless they have some direct link (Step 4 above).

The preferred solution, though likely more expensive, is to contract with an ISP that does Hosted VOIP.  In this case, the QoS will be maintained.  Is this what you are referring to as Cloud PBX?