MCPc Blog

Increasing WiFi Speed: Emerging Wireless Standards

Few things are more certain in the field of technology than the need for speed. Gigabyte Ethernet, 10 GB, 40 GB and 4G LTE are each performance indicators based on the speed of throughput. The WiFi industry is no exception.

As a sponsoring member of the IEEE 802.11 Standards Committee, I have the opportunity to review many proposed upgrades to wireless networks. Some are concerned with security, quality of service (QOS) management or TV whitespace, but the ones that inevitably get publicity concentrate on increased wireless local area network (WLAN) speed.

IEEE 802.11 is the set of standards for implementing WLAN computer communication. This post examines milestones in WLAN standards for increasing speed, and some of the most recently proposed updates to those standards. 

IEE 802.11 History: Timeline to Track Standards

IEEE 802.11 technology was introduced in 1985 through a Federal Communications Commission ruling. It was released in 1997 with a frequency of 2.4 GHz. From there, multiple amendments to the standard have been made. Some of the most notable include:

• September 1999: IEEE 802.11a — Uses the 5 GHz and in some cases 3.7 frequency band; signals have a smaller effective range and are therefore more affected by attenuation.

• September 1999: IEEE 802.11b — Radio frequency (RF) in the 2.4 GHz frequency spectrum; theoretical data transfer speeds of 11 megabits per second (Mbit/s). (Note, I say theoretical because when you allow for forward error correction codes, the real speed was about 6 Mbit/s.)

• June 2003: IEEE 802.11g — Published speed of 54 Mbit/s and actual throughput of about 22 Mbit/s; both 802.11b and 802.11g operate in the 2.4 GHz range, competing with other devices operating in the same range (such as cordless phones, baby monitors, wireless cameras and microwave ovens).

• October 2009: IEEE 802.11n — Operates at both 2.4 and 5 GHz; doubled the channel width from 20 MHz to 40 MHz; can run as high as 600 Mbit/s (but, in real world scenarios, 200 - 300 Mbit/s is likely the highest rate achievable); its major innovation is the addition of Multiple Input Multiple Output (MIMO) antennas.

New IEEE Standards Promote Speed, at the Cost of Range

Now, two new standards look poised to replace 802.11n — IEEE 802.11ac and IEEE 802.11ad.

A logical progression, IEEE 801.11ac uses the 5 GHz range and is expected to reach speeds of 1 Gbit/s. That’s between three and four times faster than our current standard! The draft standard is due this year and it’s anticipated that IEEE 802.11ac should start rolling out in late 2012. The market research firm In-Stat predicts that, in 2015, one billion devices with the IEEE 802.11ac standard will be sold. However, another standard in development that could disrupt these plans.

Known formally as IEEE 802.11ad and generally as WiGig, this standard promises speeds of 7 Gbit/s — more than ten times faster than the current standard!

At first glance, it looks like a no-brainer: we’d all rather have 7 Gbit/s than 1 Gbit/s. The catch, however, is that IEEE 802.11ad doesn’t run in the 5 GHz or 2.4 GHz ranges. It moves way up the spectrum to the 60 GHz range. With a higher signal and shorter range, it becomes more sensitive to attenuation — meaning walls, closed doors or any barriers will have more impact than they would at 5 GHz and 2.4 GHz.

Cells at 60 GHz will be smaller and more prone to disruption. So an IEEE 802.11ad network could either take a whole lot of access points or resemble a chain of high-performance islands with big dead spots around them. While it’s impossible to predict exact cell size, in linear terms, the beam at 60 GHz will travel less than 10 meters — opposed to 30 to 50 meters we see in 2.4 GHz and 5 GHz.

WiGig in Action

Even though WiGig will require wireless network redesign and result in kludgy cells, it will be worth it. Take the following example for home users:

HDTV requires 3 Gbit/s. IEEE 802.11n running at 300 Mbit/s isn’t fast enough; neither is IEEE 802.11ac at 1 Gbit/s. IEEE 802.11ad at 7 Gbit/s will eliminate streaming, choppy video, and all that has prevented us from getting video directly from the Internet. So don’t rush to buy a 3D TV just yet. It will likely be obsolete next year when IEEE 802.11ad-enabled sets begin to hit shelves.   

What to Do in the Meantime?

The good news: manufacturers don’t have to choose between a WiFi network that provides adequate coverage areas and one that provides the speed you need. Next year, we’re likely to see tri-band network devices that will operate in 2.4, 5 and 60 GHz.

You could cover all areas with 60 GHz IEEE 802.11ad, but that will be very expensive. More likely, you’ll design room-sized areas where high bandwidth is needed, including ad standard with IEEE 801.11ac, suggesting that legacy devices using 2.4 GHz will gradually fade away and abandon that frequency to microwave ovens. But don’t count on it. Historically, every time there’s been bandwidth available, someone’s come up with a creative use for it.

Your Thoughts?

With standards held up in IEEE task groups, the promises of 802.11ac and 802.11ad may take some time to come to market. Would your company benefit from increased speed at the cost of range? What are your thoughts?

Bill Cannon is Vice President of Business Development at MCPc, and an IT industry veteran with expertise in networking and telecommunications technology. Connect with Bill on LinkedIn.

 

 

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Hedy Lamarr and the Secret History of Spread-Spectrum Technology

The recent death of Elizabeth Taylor caused a spate of tributes and reminiscences about her movies, husbands, divorces, scandals and more. I didn’t see any articles about her contributions to technology, but that isn’t surprising. We don’t typically equate celebrities with major technological advances.

Imagine a press conference held by Cisco to announce a technology breakthrough so important that it will influence technology for the next sixty years or more. Now, imagine that they bring the people responsible for this new technology out on stage – Snookie and The Situation. It sounds implausible, but there is a historical precedent for just such an announcement…

The Most Beautiful Technology Innovator in the World

Radio stations are assigned a frequency by the government. Each station pays for its own frequency, and no one else is allowed to use it. Because the number of frequencies is very limited, prices tend to be high — most of us couldn’t afford to buy our own frequency. That’s where the work of Hedy Lamarr comes in.

In the late 1930s and through the ‘40s, movie star Hedy Lamarr was advertised as “The Most Beautiful Woman in the World.” There were those who would have argued for Taylor, but no one disputed that Lamarr’s looks were stunning.

There were some dramatic differences between the two women: Elizabeth Taylor became the most famous movie star in the world. Hedy Lamarr had a largely undistinguished film career and is mainly remembered for being lampooned by Harvey Korman, who played “Headley Lamarr” in Blazing Saddles.

There is at least one other difference: Hedy Lamarr changed the course of telecommunications history.

Lamarr’s Contributions to Telecommunications

Lamarr was born in Austria but immigrated to the United States, in part, to escape Nazi rule. Her first husband was a munitions supplier to the German government. She saw the destruction they were creating and fled to divorce him, but through their relationship she learned about military technology.

Her ex-husband’s firm had been supplying the Nazis with torpedoes and focusing on how to control them. Some torpedoes were aimed at targets ten miles away or more, so putting a wire on them wasn’t practical. A better approach, they learned, was radio frequency (RF) waves. However, these had problems as well because an enemy could intercept the broadcast and use the same RF frequency to jam the torpedo.

In America and remarried, Lamarr, with help from avant garde composer George Antheil, came up with a solution inspired by Antheil’s experiments with automatically controlled musical instruments: send messages between a transmitter and a receiver, but keep changing frequencies among 88 she designated, using random patterns. Because radio waves move so quickly, it would be almost impossible for anyone to intercept even a single communication.

The remaining problem was how to keep the transmitter and receiver in synch. Lamarr solved this be creating paper cylinders, similar to those on player pianos, that had identical perforations in a pattern to delineate the frequency path. Rolls with the same pattern were installed in both the transmitter and receiver, and when started at the same time they would remain in synch until the torpedo reached its target. 

The Navy, unfortunately, saw too many failure points in Lamarr’s design, and her patented Secret Communications System never played a role in the fight against Hitler. The idea, however, didn’t go away.

Mass Adoption of Spread-Spectrum Technology

In the 1950s, Sylvania engineers started using the Secret Communications System, now renamed spread-spectrum with digital media rather than paper rolls. Presidents Kennedy and Johnson used it for their secure communications.

For the next twenty years, spread-spectrum remained a military-communications technology, but by the mid-80s it had been declassified and was now known as frequency hopping because the transmission jumps from frequency to frequency. As commercial developers began to incorporate spread-spectrum technology, it evolved to become an integral element of CDMA (Code Division Multiple Access), the dominant standard for cellphones in North America.

It’s a critical part of the standard because as people buy more cellphones there is a great need for efficiency in using radio waves. Spread-spectrum allows us to simultaneously communicate over the same bands of spectrum without appreciable interference. It also provides encryption possibilities for enhanced security.

So, there will be books and documentaries celebrating the life and accomplishments of Elizabeth Taylor, and Hedy Lamarr won’t be much more than a footnote in some of these books. But this increasingly obscure beauty made a significant technological contribution that continues to resonate in our lives today.

Bill Cannon is Vice President of Business Development at MCPc, and an IT industry veteran with expertise in networking and telecommunications technology. Connect with Bill on LinkedIn.

 

 

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SIP Trunks: Basics and Benefits

You may have heard about “SIP trunking” or using SIP to reduce your telecommunications costs, but you may not be exactly sure what it is or if it’s a strategy your company should consider. Here I offer a basic explanation of what SIP is and how it may help your company save money and gain greater telecom flexibility. 

Telecom costs are continuing to decrease. Costs for IP (Internet Protocol) phones systems, local and long distance rates and data circuits have gradually reduced over time. I am reminded of the story of the farmer who drove to the local co-op to buy bales of hay. He asked how much a bale costs and the store owner said, “well, the more you buy the cheaper it gets.” At that the farmer replied, “great, keep loading ‘em up on my truck until it’s free!” So goes the telephony market except for the fact that it actually never really gets to “free.” 

SIP Basics

SIP, or Session Initiation Protocol, is simply another way to deliver connectivity to your phone system for local and long-distance calling. Rather than using traditional PSTN (Public Switched Telephone Network) circuits such as T-1s, PRIs or analog lines, many service providers offer SIP. SIP trunks are delivered through your data (Internet) connection rather than via traditional PSTN trunks.

The cost for SIP trunks is much less than traditional circuits, and the measured per minute rates (local/long distance) are equally cost-effective. Companies can save quite a bit by using SIP trunks, but you will need to have the proper equipment to take advantage of SIP. There are four components needed to use SIP:

1. An IP-based phone system capable of accepting SIP trunks
2. An Internet connection robust enough to handle the SIP traffic
3. A gateway device to allow the SIP trunks access to your network
4. A service provider to deliver the SIP Trunks

How to Set up Your Environment for SIP

Virtually every phone system manufacturer today offers IP-based phone systems or hybrid systems that use digital and IP handsets. You need to ensure that your phone system will accept SIP trucks as the connection to the outside world. Today, SIP compatibility can be done inherently with most systems, or via an appliance that will translate the SIP trunks to your phone system.

If you do not have an IP-based phone system, you may still be able to take advantage of SIP. Some providers will offer SIP service through an IAD (Integrated Access Device), which splits your connection between voice and data. The IAD will “hand off” the trunks to your phone system as analog, PRI or T-1 trunks, whichever your system is set to handle. From your phone system the lines appear to be normal PSTN trunks, however at the carrier side, the traffic is handled as SIP.

Make sure that your Internet connection is stable and large enough to allow IP voice (SIP) traffic. Some SIP providers require you have their circuits as your data connection, while others simply use your existing circuit.

Either way, if you have a small DSL connection and want to run 50 voice calls over it, you may find that your connection does not have enough bandwidth to support your needs. In that case, consider upgrading your data connection or use a combination of SIP and traditional PSTN circuits to balance your connections between the two.

The SIP provider should be able to give you some guidelines that specify how much bandwidth you need for the call volume you anticipate.

Lastly, since SIP trunks come over your Internet connection, you need to be sure your network will allow the traffic to pass to and from the SIP provider. This typically means that your firewall needs to be set to allow the traffic, while maintaining the appropriate security. You may also be able to prioritize the voice traffic on your network to help QOS (Quality of Service) for your calls.

SIP Benefits

Remember, simply using SIP will not make all your telecom expenses go away, but you can expect a significant reduction in monthly or annual costs. SIP-to-SIP calls are by far the least expensive calls to terminate, however many companies you call may still have traditional circuits, which means the SIP provider must translate the call at some point onto a PSTN circuit and thereby incur some measured costs (cost per minute).

Other advantages of SIP include the ability to have local phone numbers in different cities which terminate to one location via a data circuit. This can be advantageous for companies wishing to have a local presence phone number without a physical site.   

Getting Started With SIP

We are seeing more companies adopt SIP strategies within their overall portfolio of telecom solutions although few have converted completely to SIP. Most have used SIP as an additional resource and balance their connections between traditional PSTN and SIP. Adopting this strategy will provide the best of both worlds and give you some redundancy in the event of issues or problems with one specific route.

Has your organization made the switch to SIP? What benefits are you seeing? Or, if you’re considering SIP, what questions do you have about it? Please share your experiences or concerns in the comments below.

Frank Marro served as Regional Vice President responsible for sales management in Cincinnati, Dayton and Columbus, Ohio. He also directed MCPc’s national carrier service program, which provides solutions for clients looking for voice, video and data circuits for WAN connectivity.

Economical and Effective Redundancy Solutions

Many companies today rely heavily on Internet connections for data connections, Virtual Private Network (VPN) links or web access to critical sites. Operational processes are greatly affected if their circuit goes down or develops speed issues. At a minimum, this can cause wasted productivity. In extreme cases, it could result in lost revenue, lost clients or low customer satisfaction. 

Companies want to build redundancy in their circuit connections, however, tight budgets may not support the cost of two major internet connections. Even if costs were not an issue, true redundancy may not be achieved by simply having two different circuit providers due to the fact that most local connections are delivered over common paths into the building (the same entry points, same telephone pole and so on). In such a case, a storm or accident that takes out that access means both circuits are down and thereby defeats the redundancy initiative. Finally, bringing in two connections requires some fancy networking to allow inbound and outbound traffic to sync up seamlessly in the event of a failover scenario.

So what can be done to achieve redundancy without the high cost and inefficiency? Recent advances in telecom carrier solutions offer several options for small-to-medium-sized businesses.

Wireless Networks

Over the past few years, there have been significant improvements in wireless networks and the fact that carriers are constantly expanding coverage presents a clever, cost effective solution: Companies can have their primary connection (T-1, 10meg, etc.) and then purchase an inexpensive wireless connection at typically less than $100 per month. The wireless service is robust enough to be used as an emergency back-up, yet costs only a fraction of a typical primary circuit. 

Wireless provides another real benefit — no local loop! Therefore, a storm that takes out your local access typically will not affect the wireless link. Additionally, manufacturers such as Barracuda Networks and Sonicwall provide cost-effective appliances that will link two or more connections seamlessly. This takes out the complexity of programming the paths and routes, and makes deployment of this solution relatively easy.

These devices can be designed to route different traffic to specific connections. As an example, you may want your main business traffic to go out the primary circuit while standard Internet or non-critical data traffic routes out the low cost circuit. This will improve performance since you can reduce non priority traffic on your primary path which frees up critical bandwidth. In either case, the links failover to each other in the event of a circuit outage and alerts can be sent to appropriate individuals within your organization via email.

Cable and DSL

Cable and DSL options provide similar benefits to wireless: They are typically low cost and in many cases take a different path into the building to provide redundant access points. If your provider plans to use the same access path as your standard telecom demarcation, request that they use a different path if possible. Even if they charge additional installation fees for the diverse routing, the one-time cost may well be worth the advantage in redundancy.

Flexible Circuits

Finally, consideration may be given to flexible circuit options now offered by several carriers. Simply put, the carriers will install a circuit that has the potential to go, for example, 10Mbps, however they only set it for 1.5Mbps. In the event of a failure of the main circuit, the redundant carrier is called and their datacenter turns up the bandwidth to 10Mbps. This process can happen within minutes. This provides the cost benefit of a lower circuit for a backup, but when needed, it can quickly scale up to the faster speed. 

In this case, you most likely will pay a premium for the higher bandwidth when turned up, but given the fact that you are in an emergency situation, the additional cost is not as much as a concern at that point considering the alternative of being down. Once your primary circuit is back on line, you simply notify the redundant carrier to turn down the bandwidth back to the idle speed. Therefore you have only paid for the higher speed when you really needed it.

Improved Efficiency for Any Business

Even a small business can deploy redundancy now at a reasonably low cost and without a network engineer, as newer network appliances take the difficulty out of implementing the various solutions.

These are just a few of the ideas that companies are using to provide redundancy at economical prices. What cost-efficient redundancy solutions has your business used?

Frank Marro served as Regional Vice President responsible for sales management in Cincinnati, Dayton and Columbus, Ohio. He also directed MCPc’s national carrier service program, which provides solutions for clients looking for voice, video and data circuits for WAN connectivity.

Telecom Solutions 101: Voice & Data Circuit Basics

Every company, regardless of size, needs connectivity to the “outside world” for voice and data.  Small offices typically use simple analog lines and DSL or cable Internet for cost effective connections. Larger offices need higher capacity for voice connectivity and higher bandwidth for data applications such as Voice over IP (VoIP), video or other data applications. Let’s review the options, how they scale and the benefits of the different solutions.

Voice Connections

The basic voice connection is a simple analog line, commonly referred to as plain old telephone service (POTS) line. Virtually all phone systems accommodate these circuits and companies who use them run local and long distance service over them. Local phone companies still offer features such as call forward, roll over, caller ID and call waiting for a fee. Other businesses may still use a service called CENTREX lines, which used to be popular when phone systems were too costly for smaller companies.

At some point, as a company grows — possibly when you get to 8 or 10 analog lines — it may be more cost-effective to upgrade from analog service to digital service. Most growing companies will migrate to a PRI (Primary Rate Interface), which is a digital circuit that provides 23 digital trunks for inbound and outbound calling. A similar service is a DS-1 or T-1 line, which provides 24 digital channels. 

PRIs and T-1s are used for companies that do a higher volume of calling. This is because PRIs and T-1s offer more trunks (lines) for less cost as well as lower long distance rates.

One thing to be aware of with PRIs is whether the service is “measured” or “non-measured.” “Measured” means that there is a limit on the number of local calls that can be made without a per-minute fee, while “non-measured” means that all local calling is included in the monthly fixed cost. In either case, long distance calls are billed on a per-minute basis.

When comparing PRI costs, remember that a lower cost might mean it is a measured circuit and you will end up paying for local calls. In most cases, a non-measured circuit is preferable because for a slightly higher monthly fee you do not have to worry about how many local calls you are making.

Voice circuits can grow from PRI or DS-1 to larger voice circuits such as DS-3 or OC-3 that high-end call centers or very large companies use. 

Data Connections

Data is where the largest growth and changes have been made in recent years. Carriers have upgraded their networks to deliver high-speed data at very competitive costs.

When we refer to data, we are typically referring to the connections to the public Internet or a private network connection between offices and/or cities. This becomes important when companies want to run voice and video over their networks. The circuits must have the bandwidth to handle the traffic and more importantly, they must have QOS (quality of service) or COS (class of service) to allow the prioritization of video and voice traffic over simple data traffic such as Internet browsing or email. This makes for a much clearer connection and is imperative for eliminating jitter or latency on voice and video transmissions.

Simple Internet access comes in many flavors. On the low end you have “shared services” such as DSL or cable modems. These are low-cost solutions that can be very effective for small offices.  

Beyond those services we move into the traditional Internet circuits. These can be T-1 (1.5 Mbps) or multiples of T-1s (3.0 Mbps, 4.5 Mbps, etc.), and can reach up to and beyond DS-3 (45 Mbps) speeds, but typically require that you terminate the circuits with your own equipment such as routers.

Better yet are Ethernet solutions which do not require client hardware (routers) and are delivered as an Ethernet hand-off. These are very scalable and flexible and usually start at 10 Mbps and go up from there, most commonly up to 100 Mbps. 

Are you confused yet?

Sometimes it is confusing when you compare the low-cost cable Internet service you may have at home that is 10 Mbps to a commercial T-1 that is only 1.5 Mbps, and you may wonder why there is such a difference in cost for a seemingly lower speed circuit? The main reason is due to the fact that in most cases, DSL and Cable solutions are shared services, meaning that many other customers share your connection, and may use the same access that you have at different times, therefore you have the potential to experience disparate performance. (Have you ever noticed at home that sometimes your Internet is really fast and other times it’s slow? Well, that’s why!) 

For business circuits, the access is not shared and is instead totally dedicated to that one customer so the speed is fixed and symmetrical (same speed up and down). The up and down speeds on shared services are typically different, i.e. 3 up – 10 down. This is most prevalent in DSL, for example, ADSL or Asynchronous DSL (speeds up and down are different) verses SDSL or Synchronous DSL (speeds up and down are the same). SDSL is sometimes called Commercial Grade DSL.

Wireless data connections are also becoming popular and carriers such as Lightyear, Verizon and Sprint have offerings that are cost effective and have decent bandwidth.

WAN (Wide Area Network) Connections

Companies that have multiple locations need connectivity. Often, the connections must be compliant with industry regulations relating to security (healthcare, financial, and so on). The simple way to do the connections is through Virtual Private Network (VPN) connections over the public Internet. As long as the site has an Internet connection, a secure VPN can be established using firewalls or other similar hardware. This is the most economical solution for WANs, however it has its drawbacks.

VPN Firewall

As mentioned earlier, the challenge with VPNs over the public Internet is that there is no QOS or COS, so all packets travel at the same priority. Voice or video do not have priority over any other data, often causing quality problems. For this reason, VPNs are not a solid solution for any site that has more than a few employees or where the demands for voice and video are high.

Options beyond this are to install either point-to-point private networks or MPLS (Multiple Protocol Label Switching). A point-to-point circuit is a good solution if there are only two sites and no growth is expected.  However, if there are more than two sites or plans to expand, MPLS is the absolute best solution.

MPLS circuits take any type of traffic (Multiple Protocol) and prioritize the way different packets (data, voice, or video) are transmitted over the circuit. This is done by tagging each packet with what type of packet it is (Label Switching). For example, if two packets hit the circuit at the same time and want to travel from point A to point B and one packet is voice while the other is data, the MPLS circuit will give priority to the voice packet. This means that you have QOS or COS with MPLS and the voice or video quality is now assured.

The other major advantage is that MPLS allows for fully meshed connectivity for multiple sites. This makes for much easier designs relating to disaster recovery solutions and back-ups.  MPLS is a private IP connection and meets all requirements for industry compliance and security and can be run through regular or multiple T-1s or Ethernet.

There are options to get Internet access off of the MPLS connections if you desire, via cloud computing solutions. This means you can share your one connection for multiple accesses and may be a better way to deliver Internet across your enterprise. Alternatively, all remote sites could “home run” back to the headquarters over the private MPLS and hop on a single Internet circuit at that point. Which option is best depends on the design philosophy within your organization.

Hybrid Circuits

Finally, we need to briefly touch on the converged circuits that most carriers offer. They can be called different names such as “Converged Circuit,” “Flex Circuit” or “Dynamic Circuit” but they all do basically the same thing — through one connection (1.5 Mbps, 3.0 Mbps, 10 Mbps whatever), they deliver multiple services such as:

• Local calling
• Long distance calling
• Internet access
• WAN connectivity options (ability to connect to other converged circuits in your enterprise)

Bundling the services provides some benefits such as:

• Overall costs are typically lower
• Single point of contact for everything
• One bill to pay

Additionally, depending on the carrier they may offer a bundle of long distance minutes along with the service or greatly reduced calling rates. 

These circuits are very viable solutions for small-to-medium sized businesses. One drawback is the fact that if your one connection goes down you lose local calling, long distance calling and Internet access. Therefore, some companies will install one or two analog lines outside or their converged circuit to have a safety net back up capability in the event of that circuit failing.

Summary

This discussion was intended as an overview. My hope is that for those learning about their voice and data options as their company grows, it provided a better understanding of some of the options available today.

Subscribe to the MCPc blog to stay up-to-date as we dive deeper into the subject of voice and data solutions, as well as other technology solutions important to today’s growing business.

Frank Marro served as Regional Vice President responsible for sales management in Cincinnati, Dayton and Columbus, Ohio. He also directed MCPc’s national carrier service program, which provides solutions for clients looking for voice, video and data circuits for WAN connectivity.

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