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flanker 12/4/2012 | 9:18:37 PM
re: No VOIP for Panama GÇ£IGÇÖm not sure how theyGÇÖre technically accomplishing this,GÇ¥ Frost & Sullivan's Popova says. GÇ£I think that carriers and ISPs in general have a variety of ways of bypassing regulations.GÇ¥

I disagree. It's pretty easy to rip a gateway out of a colo space. The remedies she is talking about are for high school hackers, not companies with profitability targets.







link 12/4/2012 | 9:18:34 PM
re: No VOIP for Panama So does anyone know who has actually implemented VoIP in any big way? I gather from the trade press that there is quite a bit of it in europe and in some large enterprises. I have also heard that there is also a number of the toll bypass players who have also been doing it for a while? Most of the stuff I have seen sounds strictly like a trunking application as opposed to a line side access.

I suspect that the people who have done it believe that they are enjoying a cost advantage and dont't want to advertise it too heavily because the service should be transparent to the end user and what's the point of alerting your competition to your cost advantage.

I speculate that this will likely change as more VoIP gets moved in to the line side and naturally the focus becomes not on lower cost networks but new revenue generating features that become enabled by VoIP. That's the marketing speil I hear anyway.

Any opinions on how important VoIP is to the Cisco's and Junipers? Being relatively small traffic generators, I wonder how much of an opportunity it can be for systems sold on the basis of cost per bit capability. It's hard to figure how VoIP is going to be a killer app for them unless the shift goes from capacity to features.

rfc1633 12/4/2012 | 9:18:34 PM
re: No VOIP for Panama When we talk about VoIP's quality, actually we are not talking about IP. IP itself can't provide any quality guarantee. If we want VoIP have something quality, we must find some right carrier of IP, and rely on this carrier to provide QoS guarantee.

I believe, the guys who support that VoIP have toll quality, will give out a lot of evidences. If we take look insight these evidences, you will find that they are not of IP's, they are all of a lower carrier's, say, MPLS, which is layer2, ATM, which is also layer2, FR,layer2; PPP, etc.(Upper layer, TCP's flow control not fit for real time applications, for on-line tractoin applications, it's ok; then UDP is the only choice, but UDP even have no flow contral. And, you will never expect the immediate node are TCP/UDP awared. Then I say lower layer is the only direction where you find QoS support from)

Then, the question changed to, who is QoS ready for VoIP NOW, MPLS or ATM? who have the capability to provide an end-to-end QoS guarantee, again, NOW, MPLS or ATM? This time, I believe the answer is quite easy, it is ATM. Maybe MPLS will, in the who knows future, provide QoS, but absolutely not now.

Further more, I am doubting about MPLS's QoS. In my opinion, MPLS can only support CoS, not QoS. Remember FEC, what the C stands for? Class!!! That means all packets in same class should belong to same FEC and share one LSP. If somebody implement MPLS QoS, he will break this law. He must assign every single call a seperate end-to-end LSP. Every call in different FEC, this is not MPLS want and can do. And if so, ATM's PVC/SVC is really better than MPLS now and future.

Now, it's easy to understand that practical VoIP solutions are all based on ATM backbone; also it's right, that so many people doubting about VoIP's quality, when VoIP running on IP/MPLS network.
link 12/4/2012 | 9:18:33 PM
re: No VOIP for Panama In TDM world, QoS is guaranteed because you only have so many time slots to assign and when you fill up and run out, the n+1 caller gets fast busy - no trunks available.

In ATM or IP or MPLS, we essentially have to have an equivalent or replacement for that fast busy to deny originations. Is this not accomplished by ensuring that at the TDM to packet gateway we can deny the n+1 caller from ingressing into the Traffic engineered ATM/IP/MPLS pipe. Doesn't this provide the true QoS that you speak of regarless of the transport layer?

rfc1633 12/4/2012 | 9:18:33 PM
re: No VOIP for Panama No, Nobody.

The biggest VoIP service I have heard is in China. The former China Telecom provide VoIP service in nation wide. But this service was proved to be not true VoIP later, except the price is same as VoIP's. They just using their legacy PSTN pretend to be VoIP. And, this is the best VoIP service I have ever tried, only because it's not true VoIP, it is just PSTN. What other SP's VoIP, say China Unicom and JiTong and former CNC? Both Jitong and former CNC bandrupted and let China Telecom pay the bill. China Unicom,eh...focusing on wireless only.

Before there is a way to make it real work, never waste money on VoIP.
rfc1633 12/4/2012 | 9:18:32 PM
re: No VOIP for Panama "In TDM world, QoS is guaranteed because you only have so many time slots to assign and when you fill up and run out, the n+1 caller gets fast busy - no trunks available.

In ATM or IP or MPLS, we essentially have to have an equivalent or replacement for that fast busy to deny originations. Is this not accomplished by ensuring that at the TDM to packet gateway we can deny the n+1 caller from ingressing into the Traffic engineered ATM/IP/MPLS pipe. Doesn't this provide the true QoS that you speak of regarless of the transport layer?"

My Answer:

I think you are talking about Admission Control. Yes, this is one of many key points to support QoS. If we can not deny as your said the n+1 call, every other call will be affected, because lack of BW after the n+1 join in.

To accomplish Admission Control, the AC's target must be a connection. For IP, you can't do admission control, because there is no connection. The only thing you can do in IP is per packet, through ACL(Access Control List, which is the best feather to a pre-sale engineer and nightmare to post-sale engineer. Sale it, nerver using it.)


Then, how can you know when you should deny the connection? In TDM, it's easy to achieve, there is no time slot. In packet network, there must be someone auditing on the usage of network resource. That is Routing protocol. For ATM, it's PNNI, which is both routing protocol and signalling; for MPLS, it's IGP-te,BGP-TE and rsvp-TE etc.
kokoro 12/4/2012 | 9:18:32 PM
re: No VOIP for Panama Packet Man, your faith in VoIP is moving... I really hope that it's supported by solid technical basis, and it's not son of the love for new stuff's love.

Let's assume that you speak after due consideration, OK, but please don't bring to the discussion arguments like "My comment:
Do you honestly think that these major carriers all over the world would deploy this is it did not work?"

Have you ever noticed the amount of rubbish that even large carriers have deployed through the years for the most bizarre reasons?

So, if you tell me that VoIP can work in complex and 'crowded' networks, I can even consider this as a valid standpoint, if not right now, say, in a few years from now, but please don't use flimsy conjectures selling them for convincing evidences.

Long life to packets!
wayland_smithy 12/4/2012 | 9:18:32 PM
re: No VOIP for Panama Great thread !

Few points to add to the discussion:-

Deployments:
Telecom Italia announced last week the replacement of the Class4 & some class 5 trunking network over the next 2 years by VoIP technology, replacing the legacy TDM exchanges countrywide. I think this is the biggest deployment from a sizeable carrier, although in Europe a number of other carriers use VoIP mainly for transit traffic (eg Tele2). I'd suggest that if TI are confident enough to deploy this, then there should be no reason for other major carriers to do so...in theory.
For QoS, you also have to bear in mind that TDM exchanges are NOT engineered for n->n circuits across the network: blocking is introduced not only in the network, but also by the equipment vendors in the design of the TDM exchanges (remember Erlang ?). So, as an example, a typical Class5 switch in N. America will deploy resential lines to a ratio of trunking backhaul circuits at a ratio of around 7-10:1. In fact, for those of you conversant with Nortel's DMS100, you'll know a line/trunking peripheral can support 480 backhaul circuits (Intl), but will be provisioned with up to 8x640 (5120) residential lines on the Line cluster modules, hence blocking can be easily introduced at a factor above 10:1.

Benefits :
For VoIP, there are two strategies to attack the market: firstly, cost savings on the trunking network (either by utilising existing/combined IP/ATM infrastructures OR by using toll bypass internationally) but, secondly,the real value is to the Carrier & Enterprise user in the areas of feature deployment and mobility. For example, I'm currently sitting in an international office and receiving calls on my "softphone" via my PC, whose PSTN number is assigned to me in a different country. If I don't like the PC Softphone, I can just log into one of the IP phones on the desk and calls to my home number are routed automatically to this phone across international boundaries (and, yes, the carrier will lose money on this !) This mobility allows customers to reach me anywhere I am connected to a LAN on one number. This would not be possibly on TDM infrastructures (god knows, we tried to sell PSTN Intelligent Networking for years at Nortel !) but the main reason is not necessarily technical, but that different countries do not allow interworking to take place of features or telephony/E.164 numbering plans - this is particularly difficult outside of the US also, when signalling systems for each countrty are non-standardised across international boundaries.
It could work if one deployed a complete private network, but who will deploy this sort of network on an international basis - this is why VPNs were introduced.
So for the future of VoIP, the selling point will be features such as mobility and the ease of provisioning/managed services rather than pure transmission cost savings.

Banning VoIP : this is more prevolent thsn you think. A couple of years ago, I did some extensive research into deploying VoIP systems in Europe. What exists in many countries in Europe are restrictions that "indirectly" also lead to a ban on VoIP commericalisation for carriers. For example, countries like Denmark & Germany insist on network "break-in/break-out" round trip delays of <35ms for transit - difficult on TDM networks, almost impossible on VoIP networks (the standard for GSM is (or used to be) 125ms). Other restrictions such as, in Germany, every voice call has to be capable of being monitored also causes implementation issues & issues of "political" acceptance....so the uptake of VoIP commercially will depend on a number of factors beyond QoS and voice quality (which, I believe on a personal note, is not an issue on a well engineered VoIP network: I have worked on TDM systems for 20+ years and there are as many "ropey" TDM networks as there are VoiP). Having recently been placed on an IP PBX system, however, I can say that the future of voice will be in this technology (particularly in the Enterprise) - I have had more useful mobility features enabled in the last 3 months on the IP system than we could ever have designed on traditional PBXs, and with no perceivable drop in voice quality. For the TDM heads out there, my suggestion would be to try it before you knock it - take this from a converted TDM skeptic !
rfc1633 12/4/2012 | 9:18:31 PM
re: No VOIP for Panama Thanks to wayland_smithy, I learned a lot of real experiences about VoIP.

More discussions follows:

"Deployments:
...For QoS, you also have to bear in mind that TDM exchanges are NOT engineered for n->n circuits across the network: blocking is introduced not only in the network, but also by the equipment..."

Here, I think QoS and blocking are two different things. When I make a call, it failed. Maybe it is because somewhere busy, blocked. This kind of blocking is acceptable. People will try other method to contact each other. What QoS mean? When I make a call, yes, connected. But there is bunch of noise, and not stable, even down suddenly. Then, try again, same thing happened, connected, quality is not good, down occasionally. This is a QoS issue. QoS issue is unacceptable, and will driving you mad.

"Benefits :
It could work if one deployed a complete private network, but who will deploy this sort of network on an international basis - this is why VPNs were introduced
So for the future of VoIP, the selling point will be features such as mobility and the ease of provisioning/managed services rather than pure transmission cost savings"

Do agree with you at this point. The other word, if VoIP only fit for VPN, that is to say, for Service Provider, there is really no need to implement VoIP. For enterprises, who have their own VPN, VoIP will be a pretty good solution.

But for mobility, it's not that simple as you said. If you roaming freely, without any extra pay, that means there must sb else pay for that. This must be SP. If so, why SP stupidly provide such service? Think about wireless phone, everybody will pay for roaming. The only reason why you don't need to pay for roaming in VoIP is, SP can't control or can't accouting on your roaming. This is another evidence to show that SP should not deploying VoIP solution.

Finally, if VoIP can't saving cost of transportation, then what it can take to SP? How can these SP who deloyed VoIP earn money? NoWay!!
So, if you are a service provider, and want to make money, don't using VoIP solution!



Packet Man 12/4/2012 | 9:18:31 PM
re: No VOIP for Panama Your comment:
Packet Man, your faith in VoIP is moving... I really hope that it's supported by solid technical basis, and it's not son of the love for new stuff's love.

My comment:
All I ever wanted to bring to the table is to set the record straight in regards to two of the most inaccurate statements that I keep hearing over and over. (1) IP cannot deliver QoS. That is piece of crap, IP QoS is becoming very mature and works very well if set up right, with the right gear. (2) You need ATM to deliver QoS. Also a piece of crap. You do not need ATM. If I were to be involved in a greenfiled carrier network, I would have IP/PPP/Sonet, not one shread of ATM. ATM is dead. Now if you are a major carrier and gots lots of existing ATM then sure there is sound business sense to put voice on ATM. I won't comment on MPLS cause I know almost nothing about it. If anyone tells you that you NEED ATM to make Voice over packet work they probably represent a ATM division of some vendor.

Let face it. IP voice is solid, if engineered right. If any of you say you did it and the quality sucked then you did it wrong. I was challenged in a previous article that I knew nothing about anything, didn't even know what a router was. So I had to post a sample config of one of my routers with IP QOS using DSCP to shut him/her up. There are dozen of very large companies who have put their entire business on IP, and that includes voice, and are reaping the benefits.

Now there are some 10-10-xxx VoIP Internet players out there. I'm willing to bet that if you made a call on some of them, during the right time of day, maybe to a certain place in the world, the voice quality will be less than perfect. Why? Cause the Internet as a whole does not have QoS and peering points can often congested. But do the customers care? BIG FAT NO. All they care about is the big CHEAPO calls they can make. So for those of you who say they made a call to some overseas land and the voice quality sucked, I say so what? You can call through the PSTN to certain parts of the world and get crap voice quailty too, and pay anywhere from $.10/minute to $.50/minute, instead of the $.03/minute with VoIP.

I am coming to one conclusion thought. A lot of the arguement put forth against VoIP has been from two fronts. (1) People with ATM interests. (2) People with traditional legacy Telco interests.

I suspect alot of the big telcos fear VoIP simply because they will lose major major revenue in the near few years to come. I foresee serious problems in the voice-switching side of the buiness. Transport will always be reasonalbly good buiness because all the Internet circuits have to get carried. With the new slew of devices/software coming out it will be getting very easy for organizations (business, families, etc) to create virtual "dial plans" to link there contacts. They will need little services from a Telco/ISP to help them set up their own calls on the Internet. If govt/industry steps in to block IP TCP/UDP ports then people simply use diffent ports. Much like the music industry. And if they start blocking all the ports then we might as well turn of the Internet, and all go back into caves.

I encourage people to put forth opinions that VoIP does not work. Its all about healthy discussion. I challenge the Nay sayers to give us examples of where a carrier or large enterprise recently tried pure VoIP and failed. VoIP five years ago does not count, IP QoS was pretty much not possible then. Bet ya won't find one case study where it could not work. Now go out and find examples of where pure VoIP has been implemented with success. You will find more than you can shake a stick at.

Me
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