Wednesday, February 17, 2016

Are Your T1 Lines Saturated?

By: John Shepler

The ideal network connection is transparent. Regardless of whether the link is twisted pair copper, coaxial cable, fiber optic or wireless, if it does anything to affect your network traffic, it is clearly not transparent. The more you notice link limitations, the more your productivity will suffer and the more you need to do something about it.

Low Bandwidth Poster. Get yours nowArtificial Limitations
Best effort shared broadband services, like Cable BB, DSL, 4G Cellular or two-way satellite are limited by both technology and policy. Each type of service has its own capacity for traffic. That capacity is generally available 24/7, aside from occasional outages. Even so, you have access only to a portion of that capacity.

The first limitation is bandwidth. You are entitled to the level of service you order, as a maximum and not a guaranteed throughput. Providers manage this by rate limiting your connection to the service. The line might be capable of 1000 Mbps, but you get 10, 30 or 100 Mbps. Thats the highest bandwidth you can achieve even if there are no other users.

The second limitation is usage limits. These are particularly severe on wireless & satellite links where bandwidth is expensive. Limits of 5 or 10 GB per month severely limit what you can do with the service. Even higher limits of 20 or 50 GB may not be enough for normal business activities. If you go over your limit, you’ll either be charged more, have your connection dropped or have your bandwidth throttled for the rest of the month.

Actual Limitations
Private lines and dedicated Internet access connections usually don’t have artificial limitations. You pay more for these services because you are the only user. There is no need to create policies to ensure fair usage.

Technical limitations remain. Each technology has it’s inherent limitations. There’s no such thing as unlimited bandwidth, even on your own LAN network. What you want is enough bandwidth available that you never run out of capacity.

T1 Line Saturation
T1 lines have been the gold standard of business connectivity since they were introduced decades ago. T1 lines are dedicated connections between two locations or between your location and the Internet. You are the only user and there are no usage limits. The line is constantly running and available to transfer data. You can use as little or much of the available capacity each month. The lease price is fixed.

T1 lines have a bandwidth of 1.5 Mbps. Actually, the exact line speed is 1.544 Mbps. However, 8 Kbps is needed as overhead to synchronize the line, so the payload rate is 1.536 Mbps. That’s what’s available for your bits of data.

The absolute maximum amount of data you can shove through the line can be figured at 1.536 Mbps x 60 seconds/minute x 60 minutes/hour x 24 hours/day = 132,710 Mbits or 16,589 MB per day, at 8 bits per byte. That’s 16.59 GB of data each day. In a typical 30 day month, that’s just shy of 500 GB.

Line Saturation Problems
Your T1 line becomes distinctly non-transparent when you have big files to transfer and you want to transfer them fast, or you have many users wanting to transfer their files at the same time. The entire line is only capable of transporting less than 17 GB every day, not even 1 GB per hour.

What happens when you try to shove more data down the line than it can carry? Everybody’s traffic slows down… sometimes to a crawl. That’s frustrating and can lead to real productivity issues, especially when need the information to proceed with your next task.

It gets worse when your telephone system is cloud hosted VoIP. Those voice packets get jammed up with all the data packets and don’t get from phone to phone as quickly as needed. The result is garbled voices, pauses in the conversation and perhaps even dropped calls.

If you only occasionally reach line saturation, prioritizing traffic can help. Real time services, such as telephone calls and video conferences get highest priority. Whatever they don’t need can be used for interactive business applications, and whatever is left over is available for background activities like file backups.

At some point, you just need to pony up for more bandwidth. Fortunately, this is a lot less expensive to do than ever before. If doubling bandwidth will hold you for awhile, you can go from one to two T1 lines. By bonding those lines, you can double your bandwidth while the two lines act as one larger pipe.

Ethernet over Copper technology uses the same twisted pair copper lines that transport T1, but supports higher bandwidths of 10 Mbps or more. Ethernet over Fiber starts to become cost competitive at that level and can take you from 10 to 100 to 1000 Mbps, and even up to 10 Gbps if you ever need that much. Best of all, copper and fiber Carrier Ethernet services are scalable. That means you can have the line rate limited and pay less until you need the full capacity of the fiber.

Do you find yourself running out of bandwidth on your venerable T1 lines or other WAN connections? If so, check out prices and availability of higher level bandwidth services available for your business location.

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

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