Is MPLS The New Telephone Network?

The telephone network, as we’ve come to know and love it, is based on incremental improvements to the PSTN or Public Switched Telephone Network. This is a copper and fiber infrastructure that switches circuits to connect analog, cellular and digital phone calls from any party to any other party. Most business phone systems have depended on or mirrored the architecture of the PSTN to connect even their in-house calls. That’s all changing, with various technologies vying to become the next solution for connecting telephone calls.

What’s prompting the change? It’s not wireless. The cellular phone system was designed to be tightly integrated with the PSTN. The earliest cell phones were analog, with TDM and other digital multiplexed protocols following. What hasn’t happened yet is the wholesale transition to packet switched voice on the wireline or wireless phone networks.

Where packet switching, notably VoIP, has flourished is on private telephone networks set up by enterprises for their own use and on connections to the PSTN through the Internet to avoid the phone company local loops.

Why is VoIP such a big deal? More and more businesses are migrating their in-house phone systems to VoIP solutions. Part of the reason is the cost advantage of eliminating the separate phone wiring network in favor of using the corporate LAN to connect computers and telephones. Another reason is to avoid long distance toll charges by interconnecting business locations on a converged voice and data network. A third reason is features. IP telephones are really more like computers than the old desk sets. They can be integrated with business applications to provide things like “screen pops” of customer information based on who is calling.

The migration from circuit switching to packet switching was originally accomplished by replacing the traditional PBX (Private Branch Exchange) with an IP PBX. Think of the PBX as a small version of the PSTN switches that handle massive amounts of public traffic. The PBX resides on your premises and does all your in-house call connections so you don’t have to pay the phone company to make a call from one desk to another. You also need the capacity to make and receive calls with the outside world, so your PBX has to connect to the PSTN through one or more outside lines called trunks.

Trunk lines are bundles of telephone lines. Most businesses need more than one outside line. They may start off with a single analog business line and add more over the years. At some point it makes sense to consolidate all those separate lines into a single digital trunk that can carry up to 24 separate phone conversations.

Just because the trunk lines have been switched from analog to digital, doesn’t mean you are using VoIP. Yes, VoIP telephony is digital, not analog. But the digital protocol used by T1 and PRI digital trunks is time division multiplexed switched circuit, not packet switched IP. With an IP PBX, you can switch to IP telephones in-house and connect your IP PBX to the company LAN so that you don’t have to maintain the separate telephone wiring. Your connections to the outside world will still by the same analog or digital trunk lines to the PSTN.

Where you really cut the cord, so to speak, is when you replace those PSTN trunk lines with something called a SIP Trunk. This is a private line connection between your IP PBX and your telephone service provider. That service provider takes the place of the local telephone company and connects to the PSTN at their end. You can still make all the local and long distance calls you want, but perhaps at a considerable cost savings.

The alternative to the SIP Trunk is the Internet. The Internet connects literally from everywhere to everywhere. It is a massive public infrastructure that economy of scale makes very inexpensive. Connecting from telephone to service provider for residential users is done using the Internet. Many small businesses have also taken this approach to minimize costs.

The tradeoff is that voice quality over the Internet varies quite a bit. It depends on the capacity of your connection plus whatever else is happening on the Internet. Traffic jams called “congestion” can degrade voice quality with distortion and delay. One minute everything sounds great, the next minute the caller sounds garbled. If it gets really bad, the call may be dropped.

Many businesses can’t stand this variability of performance. They want the same quality of phone conversations they had with the PSTN, but with the advanced features and cost savings offered by VoIP. The technical answer has been to use a private line connection between your company and the service provider. These SIP trunks can support multiple conversations, even scaled for hundreds or thousands of simultaneous calls.

The latest development is cloud hosted PBX systems. Cloud computing offers businesses the opportunity to avoid capital investments and maintenance costs in favor of paying by the user by the month to use a cloud based infrastructure. Cloud computing has been extended to include telephone service through a cloud hosted VoIP or cloud hosted PBX system. All of your in-house switching and outside calls are handled through the cloud. You have IP telephones on your premises plus a gateway device that connects through a private line to your cloud service provider.

This is great for single business sites, but does the entire setup have to be replicated at multiple locations?

Yes and no. Yes, you still need your IP phones and gateway at each branch office or other location. However, you can route your calls through the same cloud hosted PBX. Now it becomes more sensible to connect all of your locations to your cloud service provider through a MPLS (Multi-Protocol Label Switching) network rather than pay the cost of a private line for each location.

MPLS networks are privately operated, as opposed to the public Internet, and maintain enough resources to simultaneous support the needs of all of their customers. This includes class of service tagging so that voice calls get the priority they need to maintain call quality. Each location simply needs a last mile connection, such as T1 or Ethernet over Copper, to the very large MPLS network. The network takes care of traffic routing between your locations and your cloud service provider where all the switching takes place.

One excellent example of where this approach is optimized is the XO Hosted PBX service offered by XO Communications. XO is also a network operator, so they can provide both the cloud PBX and the MPLS network to connect your business locations in one optimized system. This gives you one vendor to deal with if problems ever arise.

Sounds a little like the old Bell System, doesn’t it? You deal with a single provider who makes the connections to your phones and does the switching. In this case, you have a choice of vendors and a far richer feature set than offered in the old days of phone monopoly. Today’s cloud hosted PBX systems can include your wireless phones as well as your desk phones so that you only need one telephone number no matter where you are.

MPLS is a likely candidate to become the new telephone network. It supports hundreds or thousands of customers without interference or service degradations. Of course, there needs to be a way to interconnect customers on different networks. This is currently done by routing outside calls through the PSTN. Eventually, Network to Network Interfaces (NNI) may allow larger cloud PBX providers to peer traffic so that most of your calls will be on-net and not subject to toll charges. Even the PSTN may evolve to a very large MPLS network based on VoIP technology, abandoning the analog and TDM legacy technologies that have been the standard for the last century.

Is your company interested in more advanced phone services with potentially large cost savings? If so, get prices and features for enterprise grade VoIP and cloud services now.

Moving From OC-3 Bandwidth To Ethernet

Many medium size and larger businesses have been using OC-3 bandwidth over fiber optic connections for dedicated Internet access, video transport, remote data backup, large file transfers between sites and other high bandwidth applications. Now, there’s a newer lower cost option that can get you as much bandwidth or more for less money.

That solution is Carrier Ethernet. You may still think that Carrier Ethernet is a specialty service found in only a few areas by even fewer service providers. Not any more. Carrier Ethernet is mainstream. There is a mad dash underway to convert TDM based networks to IP packet networks. It may not be much longer that you’ll even be able to get OC-3 bandwidth services.

It’s all about the switch from telephone technology based on individual circuits to computer network technology based on packets. What’s happened in recent years is that the vast majority of traffic around the world has changed from voice to data to video. Voice is now thought of as one more service on a converged network that can transport voice, data or video with equal ease.

OC-3 is a TDM or Time Division Multiplexing technology. It has its roots in telephony, where everything revolves around small discrete channels that each carry one individual digitized telephone call. All of those channels are carefully synchronized by giving them each their own time slot in the bitstream.

So what’s wrong with that? Nothing other than the fact that using this methodology to transport packets that aren’t the same size as channels and don’t require the TDM synchronization unduly complicates the network interface and introduces inefficiencies. An OC-3 line runs at 155.52 Mbps with a payload of 148.608 Mbps.

Ethernet is the same protocol that runs on your corporate network. What Carrier Ethernet does is enable that same protocol to run for long distances on Metropolitan and Wide Area Networks.

Is there a direct Ethernet equivalent to OC-3? Not exactly. Ethernet does have standard LAN speeds of 10 Mbps, 100 Mbps, 1,000 Mbps and 10,000 Mbps. Carrier Ethernet is far more scalable, though. You can order just about any bandwidth you require. A 150 Mbps Ethernet service is pretty much equivalent to the OC-3 speed. You could, however, select 100 Mbps, 200 Mbps or some other bandwidth that more closely matches your true requirements.

Here’s something else that makes your life easier. Install a Gigabit Ethernet port and you can easily upgrade to any bandwidth up to 1 Gbps at any time. Start with 150 Mbps to match that OC-3 today and later move up to 300 Mbps, 500 Mbps, 750 Mbps or 1,000 Mbps when the need dictates. In the mean time, you’ll be paying for only what you need on that fiber optic link.

Moving from OC-3 to the next available standard of OC-12 means you’ll have to jump from 155 Mbps to 600 Mbps and wait for a technician to change out your router card or managed router. Moving from 150 Mbps Ethernet to 200 Mbps Ethernet or higher can be done with a phone call in hours or days, not potentially weeks or longer.

Best of all, Carrier Ethernet is almost always priced less per Mbps than OC-3 and similar telco services. The reasons are increased competition and a technology that is on the rise, not the decline. How much can you save by making the move from OC-3 bandwidth to Ethernet? Check fiber optic bandwidth prices and availability to find out how many competitive options are available for your business location.



Note: Graphic of router symbol courtesy of Tosaka on Wikimedia Commons.

Gigabit Wireless For TDM and IP Transport

What do you do when you need to get Gigabit bandwidth services into a building that has no fiber connection to your network? If you are XO Communications, you simply add a wireless hop using BridgeWave Communications FlexPort link. No stringing aerial wires on poles. No trenching fiber optic conduit. Just high bandwidth connectivity through the air.

We’re used to thinking of twisted pair copper and microwave wireless as the right solutions for moderate bandwidth needs. Gigabit bandwidth levels obviously require fiber optic strands, right? Not really. Point to point fixed wireless systems can give you fiber optic performance without the fiber or the optics.

I mention optics because there are laser based solutions designed to connect buildings at Gigabit levels. They are especially well suited for connecting networks between two tall office buildings separated by a freeway or river that makes installing fiber prohibitively expensive if even possible. But that’s maybe a thousand feet or so. How about when you need to link networks over a few miles line of sight?

This is the area where BridgeWave shines, so to speak. Actually, they’re using two-way millimeter wave transmissions in the 60 and 80 GHz radio bands. Those frequencies are high, but nowhere near the infrared or visible portion of the spectrum. Here’s something interesting, though. Oxygen attenuates signals in the 60 GHz band, a property unique to that portion of the spectrum. That limits transmission distance, but it also works to ensure that multiple users on the same frequency are unlikely to interfere with each other. The signal is simply absorbed by the air on either side of the narrow beam and past the receiving antenna.

If you’ve had a bad experience with RF links in the WiFi band or other microwave and UHF frequencies, you can appreciate both the interference avoidance and inherent security of the millimeter wave band. It’s likely that anyone trying to intercept a 60 GHz transmission would have to insert themselves in the path to such an extent that they would affect the strength of the signal at the intended receiver and give themselves away.

The 80 GHz band doesn’t have the oxygen absorption characteristics of the 60 GHz band, so it is better suited to medium haul rather than short haul links despite the higher frequencies. Still, the interference is minimized and security is enhanced due to the narrow beam width of the millimeter wavelength system.

The BridgeWave FlexPort80 link that XO is deploying is available in the 80 GHz millimeter wave band plus the licensed 18 and 23 GHz microwave bands for longer links. One of the attractive aspects of the BridgeWave equipment is that it is an all-outdoor solution. Some competing systems simply have an outdoor antenna with rack mounted transmission gear needed inside the building.

Another feature especially valuable for today’s corporate networks is the ability to transmit both TDM and IP traffic. The TDM capability is also being used by mobile carriers to backhaul their 3G and 4G networks from isolated base stations. It should be noted that FlexPort80 delivers simultaneous TDM + IP connectivity, making it truly a “flex port.”

Do you have a location that has been particularly difficult to supply with high bandwidth telecom services? Perhaps a combination of fiber optics and millimeter or microwave wireless transmission can get you the Gigabit connectivity you need at a cost you can afford. Discuss your situation now with one of our Telarus bandwidth consultants to get pricing and availability for high bandwidth business connectivity solutions.



Note: Graphic based on skyscraper image courtesy of Wikipedia Commons.

MPLS Bandwidth A Bargain

MPLS networks are becoming more and more of a standard telecom service offering. If you have multiple locations to link, you need to know about MPLS. Why? Because you could be saving a bundle over your current connectivity solution.

You’ve heard of cloud networks? MPLS is a cloud networking technology. This is different that cloud computing or cloud storage because MPLS is only about making connections. Whether you do anything within the cloud is another matter. This is about transport, or getting packets from point to point.

MPLS networks are privately owned and operated. If you want to get on the MPLS network, you’ll need to make arrangements with a MPLS service provider. It’s not like the Internet, which is open to anyone and everyone. The advantage of this premium-grade bandwidth service is that the MPLS network operator can guarantee bandwidth and quality of service.

But doesn’t premium-grade mean premium price? Not really. You need to compare apples to apples. In this case, you need to compare what you pay to use the MPLS network with what it costs to maintain the same quality connections another way. Traditionally, that other way has been proprietary company networks constructed from dedicated point to point lines or Frame Relay Networks.

Frame Relay is actually the ancestor to MPLS. It was developed for the same purpose. That was to connect geographically diverse locations with reliable and secure data links. Frame Relay networks served us well for decades. But they were designed in an era of much lower bandwidths, prior to the onslaught of audio, video and massive file sizes.

MPLS is the upgrade to Frame Relay. It can handle anything you need to transport in any format. The letters M-P-L-S stands for Multi-Protocol Label Switching. Multi-Protocol means that this network can handle voice, data, video and even TDM services such as switched circuit telephony. The built-in quality of service mechanisms ensure that each service gets the network characteristics it needs. You don’t have to worry about large data transfers causing your phone calls to drop.

The bargain pricing offered by MPLS networks is that the cloud is efficiently utilized to handle traffic from multiple clients. That way, you are only paying for what you need. You can always add more locations or bandwidth if the need arises. Try doing that with proprietary networks.

Does MPLS offer a cost savings for your operations? Find out with a MPLS network competitive price quote. It’s fast, easy and free.

WAN Connection Strategies

Within the corporate environment, LAN networks have standardized on twisted pair copper and fiber optic Ethernet connectivity. But once you leave the building, it's a potpourri of telecommunication standards. How do you select the right service for your needs?

Technology has divided pretty much along two lines, so to speak. They are the traditional TDM or Time Division Multiplexing standards based on circuit switching and the newer IP or Internet Protocol standards based on packet switching. Even this division is blurred because TDM networks can transport IP services and IP networks can transport TDM services.

Core network technology may not matter unless you have a specific need. For instance, Metro Ethernet can offer you level 2 switching capability so that you can connect multiple sites around town as if they are on the same LAN.

A better approach may be to go after the lowest cost service that meets your requirements. Let's take a look at some of what's available.

T1 lines are still the best choice for many businesses that need dedicated Internet connections, point to point data exchange, or outside lines for PBX telephone systems. Yes, T1 is a TDM standard. But connecting a T1 line to a packet network is as simple as installing a managed router often supplied free by the carrier. Otherwise a plug-in CSU/DSU card may interface your router to the T1 demarcation point.

T1 has a variant called T1 PRI or ISDN PRI. This is a high capacity digital telephone trunk line that gives you up to 23 outside phone lines plus Caller ID. ISDN PRI is usually a much better deal than individual analog phone lines for more than 6 - 12 lines.

One huge advantage of T1 lines is that they are almost universally available in the U.S. This is valuable for businesses located in smaller towns or rural areas where T1 service may be all you can get. But heavy competition in metro areas also makes T1 a good choice for downtown and suburban companies. Line lease rates have plunged in recent years. Bonding lines to multiply bandwidth keeps T1 being the preferred choice for many businesses. T1 lines can also be used as SIP trunks to support enterprise VoIP phone systems using IP PBX.

DS3 and SONET are the larger TDM technology services. They use fiber optic rather than twisted pair copper for delivery. Availability is generally limited to metro areas when fiber is already "lit" or easily installed.

The direct competitor to T1 and DS3 is now Metro Ethernet, also known as Carrier Ethernet. This is inherently a packet based technology and directly compatible with Ethernet LANs. Ethernet can be delivered over copper at 10 to 45 Mbps bandwidths, but higher speeds require fiber. Where available, Ethernet WAN service is often much lower is cost than other services. It can be priced at half the cost per Mbps compared to equivalent TDM services.

MPLS or Multi Protocol Label Switching is an IP network technology that is quickly replacing older Frame Relay networks for meshed connections to multiple locations. The "multi" in MPLS means it is capable of transporting any protocol, including TDM services. Most often it is used to establish a secure private network among many business locations.

Still wondering what will work best for your company. The easy way to find out is to get a list of competitive telecom services available for your location and recommendations from experts who know the industry and aren't tied to any one particular carrier. You may be surprised at how many good options you have.