Benefits of Migrating From T1 to Fiber

By: John Shepler

If you’ve been using T1 lines for years, maybe decades, you know how solid and reliable they are. Your natural inclination is to stick with what’s working. After all, why mess with success? You should know that there are really good reasons to do just that.

What’s So Great About T1 Lines?
The appeal of T1 lies in its design and technical maturity. T-Carrier technology, which includes T1, E1 and T3 (DS3) line services, was developed in the mid-twentieth century for long distance telephone trunking to replace noisy analog carriers. Being digital, it was easy to expand the role of T1 lines to carrying packets as well as PCM audio telephone calls.

T1 Service Characteristics
T1 lines come into your building on one or two twisted copper pair using the same wires that carry multi-line telephone. This means that you can get T1 just about anywhere you can get regular POTS phone service. The service is symmetrical, meaning that upload and download speed are the same. There are no usage limits. Whatever you can load on the line during the month, you can transport. This is a dedicated private line, meaning you are the only user and security is high. So, with all that going for T1, why would you want to make a change?

Time Marches On
The 1.5 Mbps bandwidth of T1 was more than enough for business users… once upon a time. Today, 1.5 Mbps is still enough for credit card verification, email, casual Web browsing, and backup for small computer systems. It’s not a bad choice for small retail operations and offices, especially in rural ares where other bandwidth services are hard to come by.

Most users are used to higher bandwidths now, even on their smartphones. They expect faster response and really need it to efficiently do their jobs. That’s OK. You can get higher bandwidth from T1 lines. It’s done by bonding two or more together to make one large pipe. The size of that bandwidth pipe ranges from 3 Mbps on up to about 10 or 12 Mbps. If you need more than that, you’ll have to look elsewhere.

How About T3/DS3?
A faster version of T1 is T3, also known as DS3. The terms T3 and DS3 generally mean the same thing, although, strictly speaking, T3 refers to the physical line and DS3 is the organization of the data.

T3/DS3 isn’t just a little faster than T1, it’s a lot faster at 45 Mbps. This is more than enough for most small operations and many medium size companies. That makes T3/DS3 the logical upgrade from T1, right?

Yes and no. T3/DS3 is, indeed, a popular line service. It’s available in many business locations, but not nearly as many as T1. That’s because T3 doesn’t use twisted copper pair wiring. It’s provisioned on a pair of coaxial cables. That’s only for the last few hundred feet at most. T3/DS3 is transported primarily by fiber optics. If the fiber passes near your location, you may be able to get T3/DS3. If not, you’ll need to stick with copper.

The Ethernet over Copper Option
A newer technology than T1 is called EoC or Ethernet over Copper. This never was a a telephone company product. It’s an extension of the LAN Ethernet protocol for metro connections. Whatever goes on your LAN can be carried by EoC.

The big advantage of Ethernet over Copper is that it uses the same twisted copper pair as T1 lines. A more advanced modulation scheme allows EoC to offer speeds ranging from 3 Mbps on up to 50 Mbps, sometimes higher. The tradeoff is that the farther you are from the provider office, the less bandwidth is available. EoC is quite popular in the 10 and 20 Mbps bandwidths.

Moving Up to Fiber
Carrier Ethernet is available over fiber as well as copper. This is called EoF or Ethernet over Fiber. Once you move up to fiber, the bandwidth limitations disappear. Fiber optic service typically starts at 10 Mbps, with 100 Mbps and 1 Gbps as popular service levels. Some companies and now requiring 10 Gbps EoC, which is more and more available.

You may already know that fiber optic service comes in two protocols: SONET and Ethernet over Fiber. SONET is an older service that is the fiber optic extension of T-Carrier. DS/T3 is generally transported to the curb over a SONET service.

Choosing Ethernet vs SONET
SONET fiber services typically range from OC3 at 155 Mbps on up to OC-192 at 10 Gbps, although higher bandwidths are available. The increments are 155 Mbps, 622 Mbps, 1.2 Gbps, 2.4 Gbps and 10 Gbps.

Carrier Ethernet works differently. There aren’t large increments in bandwidth. You can pretty much specify the bandwidth you want in the 10 Mbps to 10 Gbps range. Popular service levels are 10 Mbps, 100 Mbps and 1 Gbps. You’ll recognize these as standard Ethernet LAN speeds.

Ethernet over Fiber is not only much more scalable than SONET, it is generally less expensive. The cost difference can be dramatic in some locations. You may pay half or less for EoF as you would for SONET. You’ll still get highly reliable professional grade service with low latency, jitter and packet loss.

Are you feeling stymied by the limitations of your old T1 lines? Now may be the perfect time to migrate your connectivity to Ethernet over Fiber at a lower cost than you might expect. You’ll also be laying the groundwork for future expansion, with higher bandwidth levels quickly available as you need them.

The How and Why of 10 Gbps WAN Bandwidth

By: John Shepler

Big data keeps getting bigger. HD video will soon be supplanted by 4K and then 8K video. IT data centers are going dark, one by one, as applications move to the cloud. Where is the bandwidth coming from to handle the demand of ever higher bit rates in the MAN and WAN?

That bandwidth is coming from fiber optic carriers who realize that every organization is going to be upsizing its data pipes or falling behind competitively. A gigabit per second was considered massive bandwidth not that many years ago. Now it’s considered entry level for many medium size and larger companies. Even consumers are anxiously awaiting universal FTTH to satisfy their ever growing media demands. Is 10 Gbps unreasonable for high performance business applications? Not at all.

The next question is how do you go about acquiring 10 Gig bandwidth once you’ve made the determination that nothing less will get the job done. Here’s an overview of the 10 Gigabit Bandwidth Options available for businesses and other organizations.


Note that SONET at the OC-192 level is still a viable option for businesses seeking 10 Gbps bandwidth. It will continue to be a good choice for some time to come because the amount of installed base of SONET/SDH fiber.

However, 10 Gigabit Ethernet is coming on strong and should be looked at carefully as the service of the future. Carrier Ethernet-native networks and those running Ethernet over SONET have big advantages in scalability and ease of deployment compared to the rather rigidly defined SONET OC levels.

The trick is to get a service port installed that is capable of providing the maximum bandwidth you’ll need. If you are considering more than 1 Gbps service, then a 10 Gigabit Ethernet port makes a lot of sense. It will allow you to incrementally scale your service bandwidth from 1 to 10 Gbps without having new terminal equipment installed. The terminal equipment is most likely to be a managed router installed by the carrier as CPE (Customer Premises Equipment).

What if you are going for the whole 10 GigE right from the start? That would merit a discussion on the cost tradeoff (if any) to have a 40 Gbps or 100 Gbps port installed right away. As outrageous as it may seem from the traditional perspective, 40 and 100 Gigabit Ethernet are real service options available today for many business locations. These are likely to become common bandwidth levels as more sophisticated applications move to the cloud.

Does it make sense to opt for wavelengths or dark fiber? It depends on what you’ll be using it for. If you need to be running multiple protocols through a point to point connection, managed wavelength service can be the right move. If you are sophisticated enough to install and maintain your own DWDM equipment, then you might get the best deal by simply leasing dark fiber to the locations you want to connect. For most businesses, though, dark fiber is beyond what they really need.

How can you tell what the best option is when there are multiple choices available? Make sure you are getting competitive quotes for as many different options and carriers as possible. It’s likely that there may at least several serving your location that you may be completely unaware of. You best choice is to work with a bandwidth broker, like Telarus, Inc., to get the best deal on 10 Gigabit or other bandwidth service.

Next Stop 100 Gbps WAN Bandwidth

Big data, cloud computing and HD video are pushing the limits of what we once considered high bandwidth private line and MPLS network connections. Gigabit Ethernet is now popular with companies that have high bandwidth demands. Some firms are moving to 10 GigE, as 1000 Mbps is no longer adequate. If 10 Gigabits per second is also a limiting factor for your business, the time has come to consider 100 Gbps bandwidth.

Most of the larger fiber optic carriers have been busy upgrading their core networks to 100 Gbps. They need this kind of backbone bandwidth to avoid having to install new fiber to meet demand. Few, however, have offered this capacity to their customers.

Zayo is changing the game. They are now offering 100 Gbps as a wavelength service between major cities. The 100 Gbps connections are located in key traffic aggregation points and IP nodes throughout the U.S. This makes the service especially attractive to content producers and large ISPs (Internet Service Providers) who have inherently high bandwidth demands.

Why choose wavelength service versus SONET or Ethernet transport? High bandwidth options is one reason. Another is the ability to specify protocols and security measures. Leasing a wavelength is the next best thing to leasing an entire fiber strand or deploying your own fiber optic cabling. Unless you are in the business of operating a regional or national fiber optic network, the cost of creating all this infrastructure is prohibitive. However, leasing a wavelength may well be within reason.

Wavelength services are created by a process called WDM or Wavelength Division Multiplexing. The idea is that each fiber strand can support much higher bandwidths if fed by multiple lasers instead of just one. Each laser is tuned to operate on a particular frequency or wavelength according to a standard international grid plan. The wavelengths all shine through the fiber simultaneously, but they do not interact. You can think of each wavelength as a separate fiber for most purposes.

How much bandwidth can a wavelength carry? By using simple on-off keying of the beam, a wavelength can transport up to 10 Gbps. For 100 Gbps you would have to combine or aggregate multiple beams or use a more advanced modulation scheme such as CP-DQPSK (Coherent Polarization-Multiplex Differential Quadrature Phase Shift Key) to transmit multiple bits per symbol. With a plug-in card such as the CIsco CRS 1-Port 100 Gigabit Ethernet Coherent DWDM Interface Module, a single wavelength can now transport 100 Gbps. There is standards work underway to extend that to 400 Gbps and eventually 1 Tbps.

Zayo offers wavelength services at 1 Gbps, 2.5 Gbps, 40 Gbps or 100 Gbps. Diversity and sub-50 msec protection switching is available to improve reliability to carrier standards.you can order single or multiple waves as needed to support your applications. Zayo has the ability to scale bandwidth capacity along their routes to 8 Tbps when such a need arises.

Companies interested in high bandwidth wavelength services are also often interested in low latency. Zayo offers low latency routs with up to 100 Gbps of bandwidth between Seattle, Chicago, New York City, and Philadelphia to key data centers and financial and enterprise locations. Their low latency routes also include a hop to London as well.

Zayo will continue to deploy their 100G wavelength service across major markets for through the first half of 2013. Their entire network includes 67,000 route miles serving 45 states and Washington D.C. with 10,530 on-net buildings that include 535 data centers, 515 carrier PoPs (points of presence) and 2,743 cell towers. They also offer colocation facilities with over 141,000 square feet under management.

Does your company need higher levels of bandwidth to maintain or improve productivity or support demanding applications? If so, there are fiber optic service options available for 100 Mbps up to 100 Gbps at attractive prices. Competitive quotes are available at no charge.

Wavelength Services For The Enterprise

Once needed only by telecom carriers, wavelength services are now available for enterprise users. These higher bandwidth fiber optic services are needed by hospitals, medical centers, banks, financial institutions, service providers to government, video production and distribution houses, content delivery networks and research facilities. Every day more applications cross that threshold of needing faster pipes to transfer data. Should those faster pipes be wavelength services?

A wavelength or lambda is light at a particular frequency or color. This characteristic is generally expressed in terms of wavelength in nanometers rather than frequency in terabits per second. Just as frequencies can be multiplexed to create a broadband wireline service, wavelengths can be multiplexed to offer multiple paths through a single fiber strand.

The multiplexing process at the physical level for fiber optics is called WDM or Wavelength Division Multiplexing. There are two technologies available. CWDM or Coarse Wavelength Division Multiplexing creates anywhere from 2 to 20 independent wavelengths, with 16 being a standard. DWDM or Dense Wavelength Division Multiplexing requires more precise equipment to create from 40 to 128 or more independent wavelengths.

As you can imagine, having dozens of independent wavelengths per fiber optic core and perhaps 100 cores in a cable, the amount of available bandwidth is truly staggering. So much so, that carriers are leasing out entire wavelengths to companies and organizations that need high bandwidth conduits. Wavelength services are similar to point to point T1 lines in that you have exclusive use of the wavelength. While the wavelengths in any particular core may be leased by dozens of different users, any multiplexing on the particular wavelength you are leasing is up to you. It's a private line service, with the line being a particular wavelength of light.

What bandwidths are available on these wavelength services? Commonly available speeds are 2.5 Gbps and 10 Gbps. Other increments of 1 Gbps and 5 Gbps are also increasingly available. Need more than 10 Gbps? It's possible to get as much as 40 Gbps in some areas. Can 100 Gbps be far behind?

Another advantage of wavelength services is that they are not locked into a particular protocol. You can use your wavelengths to transport Fast Ethernet (100 Mbps), Gigabit Ethernet, SONET OC-3, OC-12, OC-48, Fibre Channel, ESCON and Frame Relay.

Who's offering wavelength services suitable for large enterprise and other organizational use? Major competitive carriers such as Level 3, XO Communications and AboveNet have these and other fiber optic bandwidth services available right now. If you have a serious application that needs connectivity at this level, find out what wavelength services are available for your business locations.

Gigabit Connection Services

If you are in need of really massive amounts of WAN bandwidth, you'll be looking at Gigabit connection services. This high level of bandwidth is indeed available, but you'll need to be in or near a location already lit for fiber optic service. That generally means within major metropolitan areas and especially within a carrier POP or Point of Presence. If so, you may find that 1,000 Mbps of connectivity can fit within the budget of even a medium size company.

Who needs Gigabit level bandwidth? Competitive telecom services vendors, of course. That includes the competitive carries with nationwide fiber optic routes. Their customers, perhaps yourself, include large medical centers, video production companies, Software as a Service providers, data centers, research organizations, large engineering companies and Cable MSOs. The list is growing every day. As businesses go more and more digital, their LAN and WAN bandwidth needs are increasing. So much so, that the availability of once unheard of metropolitan and long haul network bandwidths are becoming readily available.

The traditional fiber optic bandwidth service is called SONET for Synchronous Optical NETwork. It's a legacy telecom service based on TDM or Time Division Multiplexing technology. SONET is known for its development maturity, wide deployment, and reliability.

SONET service levels range between OC3 at 155 Mbps, to a typical Metro Ring at OC12 at 622 Mbps, and up to OC48 at 2.5 Gbps. There's also an OC24 level defined at 1.244 Gbps, but it is less common than OC48 service. OC24 and OC48 can be used to provide Gigabit WAN connections.

There are higher levels of service, but those are generally reserved for carrier backbones themselves. OC192 operates at 10 Gbps, OC256 at 13 Gbps, and OC768 at 40 Gbps. Some larger networks are now in the process of upgrading their routes to 100 Gbps, usually by bonding multiple fibers or fiber wavelengths.

The competing service to SONET is Gigabit Ethernet or GigE. This service is being heavily promoted by competitive carriers who are running IP rather than TDM networks. They can provide 10 Mbps Ethernet, 100 Mbps Fast Ethernet or 1000 Mbps Gigabit Ethernet directly from their POPs to your company via fiber optic line. Colocation services at carrier POPs or public colo centers make it easy to order GigE connections, since provisioning is as simple as dropping a cable from the carrier's equipment to yours. Even on terminations within your building, Ethernet usually has cost advantages over traditional SONET services.

Do you have a serious business need for high bandwidth connections, from 10 Mbps up to the Gigabit level? Find out what fiber optic bandwidth services are available for your location.