Monday, October 05, 2015

Ethernet Fiber Replaces Bonded T1

By: John Shepler

It’s not surprising T1 lines have been the most popular connectivity solution for businesses for decades. This is an exceptionally mature and versatile technology that you can use for private lines, dedicated Internet access and telephone trunking. The one weakness of T1 is bandwidth. It’s a rock solid 1.5 Mbps. No more, no less. In these days of cloud applications and real time HD video, what can we do about the T1 bandwidth limitation?

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Solution #1: Bonded T1 Lines
Seems like the way to double the bandwidth of a T1 line from 1.5 to 3 Mbps is to add a second T1 line. You can do this yourself with a WAN aggregation appliance like the “Truffle” from Mushroom Networks. Or, you can simply order a second T1 line from the same provider and have them “bonded.” Carriers do this with terminal equipment at both ends of the circuit.

Bonding is simply a process of melding the bandwidth of the two lines so they act as one larger pipe. The nitty gritty details of how this is accomplished is invisible to you, the user.

A nice feature of bonding is that it can be extended beyond two T1 lines. You can bond 3 lines to get 4.5 Mbps, 4 lines to get 6 Mbps, and so on. All you need are enough extra twisted pairs in your telco line bundle to provide the additional T1s. The practical limit is 10 to 15 Mbps. Then, we’re back to the bandwidth issue… and one more thing.

The Ugly Side of Line Bonding
T1 line bonding works just great. It is a well established technology that is highly reliable. It’s just that it is a bit… expensive.

The downside of bonding is not technical. It’s financial. There’s no real economy of scale when you bond T1 lines. Each line has a certain cost that is made up of loop and port charges. Nowadays this is typically a few hundred dollars per line, but varies with location. That’s a lot lower cost than in years past, but it still adds up when you need a bunch of lines to get enough bandwidth. In short, two lines cost twice as much as one. Three make that 3X, and so on.

Why Fiber Makes Sense
T1 used to be the affordable bandwidth solution, while fiber was priced too high for all the but the largest businesses. That’s all changed thanks to technology and competition.

The first big recent advance in fiber optic bandwidth service has been a transition from circuit switching to packet switching technology. The original protocol was called SONET. It’s still available and popular for some applications, such as service provider backbone networks. SONET is a circuit switched protocol designed to be directly compatible with traditional T1 and T3 telephone lines. Bandwidth starts at 155 Mbps and goes on up to 40 or 100 Gbps.

The newer technology is called Carrier Ethernet and it is a packet switched technology directly compatible with Ethernet based Local Area Networks. Carrier Ethernet can easily extend your network across town or even internationally. It also supports enterprise VoIP telephone systems when configured as SIP Trunks.

Carrier Ethernet can be available in both copper and fiber optic connections. Fiber is fast becoming the connection of choice because it is easily affordable at lower bandwidth levels and scalable up to 10 Gbps or even 100 Gbps if needed.

Why Fiber is the New Bonded T1
The obvious advantage of fiber optic transmission is getting rid of the bandwidth ceiling on copper technology solutions. While 10 Mbps is considered high bandwidth for bonded T1, it is low bandwidth for fiber. Once you have fiber installed, you’re set for the future.

This is especially true for Ethernet over Fiber technology. It is designed to be easily scalable up to the limit of the installed port. Say you have a 1000 Mbps port installed, a typical service option. You can then order any bandwidth you like up to 1000 Mbps without any equipment changes. A simple phone call is all it takes to change your bandwidth, often the same day. Some carriers even allow you to manage your own service through a Web browser.

Nearly unlimited bandwidth is one advantage of Carrier Ethernet. The other is cost. While bonded T1 costs scale linearly with the number of lines, Ethernet over Fiber costs go up much less between bandwidth levels. A 10X bandwidth increase with T1 can cost 10X as much as a single line. The same 10X bandwidth upgrade might raise the price only 3X. Even at the low end of the bandwidth scale you can often get at least twice as much bandwidth choosing Ethernet over T1 for the same money.

But Is Fiber Really Available?
The competition from many new carriers offering Ethernet over Fiber means both lower costs and more availability. The upgrade from 3G to 4G wireless alone has spurred a massive build-out of fiber infrastructure to support all those cellular towers. Business demands for cloud applications and higher bandwidth that can handle video and large file transfers is also encouraging more fiber construction and lower prices.

The bottom line is that fiber optic bandwidth is far more available than it was just a few years ago. If you have a new application or just haven’t checked your options in awhile, it is well worth your while to see if Ethernet Fiber can replace those legacy T1 lines to give you more bandwidth and a more attractive lease price.

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Monday, September 14, 2015

When Only T1 Will Do

By: John Shepler

In the age of gigabit fiber connections, the venerable T1 line might be thought of as a relic of the past. Not at all. T1 service is alive and well. It might even be exactly what you need right now in the way of bandwidth and affordability.

Wan Man at Your Service coffee mugs and more....Why Would Anyone Want a T1 Line?
T1 is the most mature, most deployed and most available of the telecom line services. You might think that Plain Old Telephone Service (POTS) would be the leader in that category. It was. POTS is giving way in many organizations to newer premises VoIP and telephony in the cloud. That still leaves what used to be the POTS lines connected. What are they good for? Think: T1

T1 lines are amazingly versatile. They make perfect telephone trunks for channelized T1 phone, ISDN PRI and even high quality VoIP. They are almost certainly available at your location, wherever you may happen to be. Plus, T1 is readily affordable by just about any size business.

The T1 Telephone Line
Did you know that T1 actually started out as a telephone trunking technology? If the telco companies didn’t have a burning desire to consolidate the mass of wiring that interconnected their switching centers, T1 might never have come about. In the beginning, it was one telephone conversation per pair of wires. Then the phone companies found a way to send multiple conversations down the same pair simultaneously using a method called carrier telephony. It works like the radio band. Each conversation had its own assigned carrier frequency separated from the others so they wouldn’t interfere. This is the analog way to get the job done.

The breakthrough that was T1 involved the conceptual change from analog to digital. By digitizing the phone conversations, you could send 24 of them down the same pair of wires and they wouldn’t interfere. What’s more, digital technology got rid of all that noise and crosstalk that analog long distance lines were famous for in the first part of the last century.

A channelized T1 telephone line consists of 24 time division multiplexed segments or channels that are synchronized at the transmitting and receiving end. Each analog phone signal is digitized into 8 bits by 64 Kbps, which preserves the call quality. What grade of wiring do you need to transmit these calls? Ordinary twisted pair telephone cable will do just fine. With signal regenerators every mile or so, a T1 line can be stretched as far as you like.

ISDN PRI Telephone Trunks
T1 telephone lines are used by in-house PBX business phone systems. In recent decades, that technology has been upgraded to something called ISDN PRI or Primary Rate Interface. It’s the same T1 line, but with a slightly different format. ISDN PRI provides 23 separate phone lines plus a control and signaling channel that runs the system. This is the preferred option for call centers because of its fast connection times and high voice quality. Multiple T1 lines can be installed to most PBX systems to match the number of outside lines needed.

T1 for VoIP
VoIP or Voice over Internet Protocol is a different method of achieving the same phone service. VoIP was designed to be compatible with computer networks rather than a unique telephone standard. Even so, VoIP trunks, called SIP trunks are needed to get the phone calls to the telephone service provider in the cloud. Unchannelized T1 lines work great for this because they are highly reliable and offer enough bandwidth to carry two dozen or more simultaneous telephone conversations.

T1 Internet Lines
T1 for Internet access, with its paltry 1.5 Mbps bandwidth might be considered laughable in this age of gigabit broadband. It’s not so funny when your business is on a farm or so far out in the wilderness that you are lucky to have a landline phone. Those landline phone wires can also carry T1. That means if you can get phone service, you can get at least T1 broadband where there is no fiber or even cell towers for miles.

Is 1.5 Mbps truly a problem? It likely is if you want to transfer HD video production. Not really, though, if you have a small business and need the line for credit card verification, a connection back to a franchise office, or just email and casual web browsing. You can increase this bandwidth by combining, called bonding, multiple T1 lines together. This will give you anywhere from 3 to 12 Mbps, depending on the number of lines you bond.

How About The Cost?
People who think T1 is expensive remember back a decade or two, when a single T1 line would set you back at least a grand a month. Today, that figure is more like $200 to $300 in most cases. It still depends on how much competing service is in your area and how far you are from the telco office. Is this expensive? Business grade cable broadband is also priced in that range, but with “up to” higher advertised bandwidth… if you happen to be next to where the cable line runs. Even then, cable is shared bandwidth while T1 is dedicated to your particular company.

If your need is for highly reliable PBX telephone lines, point to point private lines, dedicated Internet access or rural broadband applications, T1 might still be the optimum service for your company. Check out T1 and bonded T1 pricing and availability and compare with your alternative service options.

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Tuesday, September 08, 2015

The Lure of Fiber Lit Buildings

By: John Shepler

The mantra of real estate is “location, location, location.” That mantra is being joined by a new mantra for business, “fiber, fiber, fiber.” Everybody wants it and, sooner than you think, everybody will have it. The only question is: “Will they get it in your building or the one next door?”

White light burst blue skyscraper iPhone 6 caseWhat’s So Special About Fiber?
Fiber optic telecommunication lines used to be a niche service for special applications. You’d find them at Internet Service Providers, Fortune 500 companies, scientific labs, video production companies and the like. Only the most technically demanding and well funded operations got fiber. They might even choose to locate closer to where fiber POPs (Points of Presence) were already in-place to minimize construction costs.

This may still be true if you require enormous amounts of bandwidth for your data center or minimal latency for processes like high speed trading. In those cases, the best solution might be to pack up your gear and move it to a “carrier hotel” or “colocation center.” Even when you do that, however, you still have the problem of how to connect your offices to the data center. Yesterday, a few T1 or DS3 lines might have provided this connection. More and more, though, only fiber will do the job now.

Call It a Utility
We’re rapidly approaching the time where fiber optic bandwidth will be on the same level as electricity, water, sewer and gas. Companies just won’t consider locations that don’t provide these basics.

Here’s why. Today’s business operations have become highly automated. Paper documents are disappearing as fast as they can be shredded. Typewriter? What’s that? Everybody has a PC on their desk, a smartphone in their pocket, and probably a tablet to carry around in lieu of a yellow legal pad. Productivity is the name of the game, and that means data moves through the organization in bytes, not printed characters.

The demand for fiber has been pushed to critical proportions by the mass exodus from local data centers to cloud service providers. That means that all that data that used to flow on high speed copper and fiber lines to the data center down the hall now has to go cross-country to get to the new data center in the cloud. This requires much higher MAN and WAN bandwidths, but also low latency to enable interactive business applications and real-time services such as VoIP telephony and video conferencing.

How Much Bandwidth is Enough?
Entry level bandwidths for smaller companies and independent professional offices is now about 10 to 30 Mbps, up from a few Mbps a decade ago. Most medium size companies can make good use of 100 Mbps Fast Ethernet today and will soon need 1000 Mbps Gigabit Ethernet. In fact, Gigabit Internet access is becoming the new ISP standard for both businesses and consumers. Those large and unique applications? They require 10 Gbps and 100 Gbps services.

Fortunately, fiber handles these bandwidths with ease. Copper telecom lines drop off rapidly above 10 Mbps, even with the new Ethernet over Copper transmission technology. If you want 50 or 100 Mbps, you better be located very near to the telco office. The exception is cable broadband, which can go as high as a Gigabit (1 Gbps). The actual cable is only used for the premises connection. The rest of the network is fiber.

Fiber Bandwidth Options
The two major competing technologies for business fiber are SONET and Ethernet over Fiber. SONET is the older, more established, technology developed by the phone companies. Ethernet over Fiber is rapidly replacing SONET because it is more easily scalable and less expensive.

Scalability is important because you never really know how much bandwidth you are eventually going to need. You may start out at 10 Mbps and quickly find you need to up that to 50 or 100 Mbps. Later, you’ll want to take that up to 500 or 1,000 Mbps. Ethernet over Fiber allows you to start off paying for just what you need and then increasing the bandwidth level as needed. No equipment changes are needed as long as you have a port that can handle the highest bandwidth you require.

Getting a Fiber Lit Building
“Lighting” is the term used to describe having fiber installed and turned-up or “lit” by one or more laser sources. Once you have lit fiber in the building, it is generally easy to get all the bandwidth you need. Fiber, itself, has nearly unlimited capacity and can serve many users in the same building.

Competitive carriers are now at a fever pitch to find suitable buildings that are un-lit and get their facilities installed before someone else. Generally, a building is lit by only one competitor, who is there for the long term. All tenants contract with the carrier for the service they desire.

If you are a building owner, it is highly desirable to offer fiber optic bandwidth service as one of the utilities. You’ll need to have the suites wired (with fiber) that connects with the telecom room. Then each tenant can order what they need and pay the bill, just like with other utilities. Some building owners have found it advantageous to order very high bandwidth service themselves and then portion it out to the tenants at a profit. In effect, the building owner becomes the service provider.

Are you a building owner or tenant looking for fiber optic bandwidth service? You can find out quickly and easily if your building or one nearby is already lit with fiber. If not, it may well be worth your while to get your facility lit or work with a carrier as a group to get fiber service installed.

Click to check pricing and features or get support from a Telarus product specialist.

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Wednesday, August 26, 2015

Cable is the New Fiber?

By: John Shepler

Coaxial cable, the type deployed by the cable companies, has long been thought to be on its way out. After all, how many channels and what Internet speeds can you possibly force through that copper wire? Turns out, it’s a LOT more than anyone might have thought. Can you believe 10 Gbps?

WAN Man At Your Service T-Shirts and more. Check 'em out!There’s Fiber Under the Hood
The secret that makes it possible for ordinary coax to deliver 10 Gbps, high by even fiber standards, is that you only see the cable connector on the wall and the cable jumper to your cable modem. You might think that cable runs all the way back to the cable head-end, like twisted pair telephone lines connect directly to the telco office. That’s an illusion. Once the premises connection is out of sight, the handoff is made to a metro fiber network. The copper part is just a few dozen or a few hundred feet in length. The system is referred to as a hybrid fiber-copper network or HFC.

The Magic Box
With a wire plant that can support bandwidths as high as 10 Gbps, what else is needed is an interface to transmit and receive on the HFC and provide a 10 Gbps Ethernet connection at the user’s end.That interface is the DOCSIS 3.1 Cable Modem.

DOCSIS or Data Over Cable Service Interface Specification is a set of technical standards that describe how to use the standard “TV channels” and other open capacity on cable systems to transport high bandwidth data without conflicting with the television transmissions. It was developed by CableLabs and is supported by many equipment manufacturers.

The original DOCSIS 1.0 came out in March, 1997… just in time to support the big boom in Internet growth. It was quickly upgraded to versions 1.1, 2.0 and the popular current standard, DOCSIS 3.0. It’s a new version, DOCSIS 3.1, that is causing all the excitement for fiber-like cable.

What does DOCSIS 3.1 offer? It is capable of at least 10 Gbps in the downstream direction and 1 Gbps in the upstream direction. That’s about 10x to 30x the capacity of existing cable bandwidth offerings. It is also backwards compatible with earlier DOCSIS versions so it can be seamlessly deployed on existing cable systems. What’s still needed is for cable operators to upgrade their equipment to the new standard and get DOCSIS 3.1 modems installed at customer locations.

The Bandwidth Stampede is On
It’s not a matter of if but when cable companies will embrace DOCSIS 3.1. Verizon has been deploying their FiOS Fiber to the Premises (FTTP) system for years. Google is entering market after market, albeit slowly, with their own fiber optic Internet service. Cable has a chance to protect the investment in the systems they already have by being able to offer Gigabit and 10 Gigabit Internet access with simple equipment upgrades and no need to rewire the city.

Comcast is one major cable operator that has seen the light. They have declared an intent to cover their entire service footprint with DOCSIS 3.1 capability in the next few years.

Is This the Same as SONET or Ethernet over Fiber?
In a word… NO. These are not only different technical standards, they have different performance standards and are targeted at different types of customers.

SONET is the original telephone company standard that was first deployed to transmit thousands of telephone calls on a single fiber. As bandwidth demands escalated to connect data centers and support the backbone of the Internet, SONET was made available to businesses. The lowest service level is OC3 at 155 Mbps. The highest levels are typically OC-48 at 2.5 Gbps, OC-192 at 10 Gbps and OC-768 at 40 Gbps.

A newer technology is Carrier Ethernet. This is directly compatible with the Ethernet that dominates local area networks in nearly all companies. Both copper and fiber implementations of Carrier Ethernet are available, but Ethernet over Fiber is rapidly becoming the more popular standard. Service levels range from 10 Mbps to 10 Gbps, with 100 Gbps available in some areas.

How do Cable DOCSIS, SONET and Fiber Ethernet Compare?
SONET and Ethernet over Fiber (EoF) obviously require fiber optic connections all the way to the premises. Cable only needs the standard coaxial copper cable connection. This provides cable with an advantage as to availability and speed of installation. However, that advantage is not what it once was. More and more competitive carriers are expanding their fiber optic networks and “lighting” more and more buildings for fiber service.

Cable seems to have a big cost advantage compared to the fiber technologies, but this is more a matter of the type of service offered rather than anything to do with copper versus fiber. As proof, consider Google Fiber. It’s priced like cable, but is fiber optic end to end.

SONET and EoF are considered high performance business services and are generally offered with SLAs or Service Level Agreements that define the performance and availability of the service. Cable is considered a “best effort” service and doesn’t come with the same uptime guarantees.

SONET and EoF are what are called dedicated services. That means the assigned bandwidth is dedicated to your organization. If you contract for 10 Gbps, you’ll get 10 Gbps 24/7/365. There are no usage limits. You can drive as much data down those pipes as they’ll take for the entire month. Cable is a shared service. The bandwidth is “up to”, say, 10 Gbps. At any given time, you may have all of that to yourself, or you may be sharing it with a dozen, hundred or thousand other users. Bandwidth for shared services varies, while it is solid for dedicated users.

The other big difference is symmetry. SONET and EoF are symmetrical services. That means you get the same upload and download speeds. Order 10 Gbps service and it will be 10 Gbps in both directions all the time. Cable service is asymmetrical. Download speeds are typically 10x upload speeds. DOCSIS 3.1 maxes out at 10 Gbps download and 1 Gbps upload.

How Do You Choose?
Cable is well matched to typical consumer and small business Internet access, which is download intensive. The “shared” aspect may not make that much difference and the reliability may be high enough that the cost advantage makes it an excellent choice.

However, if you are primarily transferring big files in both directions or dependent on cloud services for critical operations, or if availability of service is critical to what you are doing, you may find that only SONET or Ethernet over Fiber will be satisfactory. Costs for both types of services have dropped dramatically in recent years, with EoF especially cost effective for high performance applications.

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Wednesday, August 19, 2015

Dark Wavelength vs Dark Fiber for 10 GigE

By: John Shepler

Organizations that require extremely high MAN (Metropolitan Area Network) bandwidth or need to run a multitude of protocols have looked to dark fiber as a technical solution. Dark fiber is still a good choice for the most demanding applications, but there is a competitive service you should also be aware of. It’s called dark wavelength or dark lambda. Let’s look at what each has to offer and how they compare with the more common point to point and MPLS network connections.

How a prism separates a single white beam into multiple colored wavelengths.What is a Dark Wavelength?
We think of wavelengths as colors of light, not something dark. A wavelength with no color would essentially be turned “off” and would be the same as a dark fiber, right?

Not really. The difference is that dark fiber is nothing but the glass fiber strand itself. There is no equipment attached. Somebody, and that somebody is likely you, has to install terminal equipment at each end and turn on one or more laser beams to “light” the fiber. Sometimes "managed" dark fiber is available, where the carrier will provide the terminal equipment but you'll still have exclusive use of the fiber strand.

With a dark wavelength, this has already been done. It’s not a fiber with a single color laser at one end and a detector at the other. Instead, the equipment that has been installed is DWDM or Dense Wavelength Division Multiplexing gear. What DWDM does is send multiple non-interfering laser beams down the same fiber strand to create what amount to additional channels equivalent to multiplying the number of fiber strands available.

With DWDM there is still only a single physical glass strand. The multiplexing or creating of multiple virtual fibers out of one is based on the fact that glass is transparent to more than a single color or wavelength of light. You can easily see this with a common prism. Shine white light in one side and bands of color appear on the other side. The prism shows that a number of separate colors can travel through the glass without interfering or canceling each other out.

Say you want to create a dozen different wavelengths on a single fiber. You’ll need a DWDM system that contains a dozen laser transmitters, each tuned to a slightly different wavelength or color. In practice, all the colors are in the infrared part of the spectrum and not visible colors. Nonetheless, they are referred to as colors, wavelengths or lambdas (the Greek letter used to denote wavelength).

Why go to all this trouble and expense? Simple: To multiply the capacity of a fiber cable. There are two ways to get more bandwidth from a fiber bundle. Either add more strands or use more of the inherent capacity of each strand. Adding strands means running an additional cable along the same route or replacing the cable you have with a larger diameter one that has more of the hair-thin glass fibers. Both options are incredibly expensive. Getting more from the infrastructure you already have is very attractive by comparison.

This is why DWDM is so popular. Why pull many miles of new cable at a cost of millions of dollars when you can upgrade your terminal equipment for a fraction of the cost? DWDM is a well established and standardized technology. Why not let technology save you the cost and delays involved in upgrading the physical cable?

The Dark Wavelength vs Dark Fiber Tradeoff
If you lease a dark fiber strand, you have exclusive use of that piece of glass. You have the security of knowing that only your traffic will travel over that strand. There will be other customers using other fiber strands, but there is a physical separation between you and them.

Dark fiber also gives you the flexibility of using any protocol you want and even setting up multiple protocols on the same fiber. How do you do that? By installing DWDM equipment of your own to create multiple independent wavelengths.

You can see how this can get to be expensive fast. A simple one wavelength fiber strand is one thing. You can probably get 10 Gbps bandwidth on that strand with simple equipment. DWDM is another matter. Now you need a fairly sophisticated piece of equipment at each end that you have to install, pay for and manage. For that, you can create multiple independent channels of, say, 10 Gbps each.

Instead, why not let somebody else bear that expense? That’s the basis of dark wavelength services. Someone, the carrier or service provider, has already lit the fiber with DWDM equipment that they own and operate. However, they don’t need all of the wavelength capacity themselves. If there is only enough traffic to use half the wavelengths available, the others can be leased to help pay for the system.

A dark wavelength is simply an unused wavelength on an existing fiber optic system. To be truly dark, the laser for that wavelength may be turned off or there is no card in the system for that particular channel. Either way, once someone agrees to lease the wavelength, service can be turned up fairly quickly. After all, the fiber and the DWDM chassis are already in place and operating.

Why Choose Dark Wavelength?
One reason to opt for dark wavelength service is that it may be all that is available. The owner of the fiber network may not be willing to lease an entire strand. That’s especially true if they have already lit their strands and are using some of the wavelengths.

Another attraction of dark wavelengths is equipment cost and maintenance. In theory, a provider could require you to purchase the channel cards that are compatible with their DWDM system and light the wavelength yourself. More likely, they will handle that themselves. You may or may not be asked to pay a one-time installation fee that includes the cost of the wavelength cards.

If the common carrier turns up the wavelength and maintains the system, you will have exclusive use of that particular wavelength at a bandwidth of 1, 5 or 10 Gbps. Sometimes wavelengths can be aggregated to create higher bandwidths up to 100 Gbps. Either way, only your traffic will be carried on that wavelength as whatever protocol you choose. Other customers will have their traffic on other wavelengths, but the different color beams will not interact.

Other Options
Not everyone needs or wants dark fiber or wavelength service. Many businesses only need 100 Mbps or Gigabit service. Both traditional SONET or the newer Carrier Ethernet protocols are generally available as point to point connections, ports to much larger MPLS optical networks, or Dedicated Internet Access.

What bandwidth option is best for your applications? Why not discuss your needs and get competitive quotes from multiple carriers for a range of services that can meet your needs. Then you can compare costs and benefits and pick the high bandwidth fiber optic service that best meeds your requirements.

Click to check pricing and features or get support from a Telarus product specialist.

Note: Spectrum of light wavelengths though a prism animation courtesy of Wikimedia Commons

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