Dedicated Internet Access (DIA) is a fiber circuit reserved for your business alone, with the same upload and download speed and a written SLA. Shared fiber gives you fiber speeds over capacity you split with neighbours, with best-effort support. Coax (cable) is the lowest-cost option and usually has a much slower upload. Which one you need comes down to two things: what an hour offline costs you, and how much you send out of the building rather than pull in.
Almost every quote you receive will be one of these three, and the price gaps are large enough that picking wrong costs real money in either direction. Overbuy and you pay every month for capacity and guarantees nobody uses. Underbuy and you find out during your busiest week.
The short version, side by side
| DIA | Shared fiber | Coax | |
|---|---|---|---|
| Who else is on it | Nobody. The port is yours. | Neighbours on the same network segment | Neighbours on the same cable node |
| Upload vs download | Symmetrical | Often symmetrical or close to it | Upload is usually a small fraction of download |
| Written SLA | Yes: uptime, latency, packet delivery, repair time | Rarely anything meaningful | No |
| Support | Business NOC, defined repair windows | Best effort | Best effort |
| Typical install | 2–4 weeks in a lit building; 60–90 days if construction is needed | Days to two weeks where available | Often days |
| Best for | Offices where downtime costs money by the hour | Growing teams that want speed without an enterprise budget | Very small sites, and backup circuits |
Dedicated Internet Access
What "dedicated" actually means
With DIA, the carrier provisions a port and a committed amount of bandwidth for your business, from 100 Mbps up to 100 Gbps. The access circuit between your building and the carrier's network is not shared with anyone. If you buy 500 Mbps, you get 500 Mbps at 9am, at 4pm and during the week everyone in the building is uploading quarterly reports. Your speed does not depend on the neighbours, because there are no neighbours on it.
It is also symmetrical. Upload runs as fast as download, which matters more than most buyers expect. Video calls, VoIP, cloud backup, sending large files to clients and anything you host all push data out.
The SLA is the real product
The part of a DIA contract that separates it from everything else is the service level agreement. A typical enterprise SLA puts uptime (often 99.99%), maximum latency, packet delivery and a repair window in writing, with service credits when the carrier misses. Shared products are sold on speed. DIA is sold on a promise, and the promise is enforceable.
When DIA is the right answer
- Phones, card payments and cloud apps all ride the connection, so an outage stops the business, not just the browsing.
- You host anything reachable from outside: a VPN, a server, a camera system, a client portal.
- You move large files on deadlines: design, video, CAD, medical imaging, legal discovery.
- A client, regulator or insurer expects a documented, SLA-backed connection.
More on the product itself on our Dedicated Internet Access page.
Shared fiber
How the sharing works
Most shared business fiber runs on a passive optical network (PON). One fiber from the carrier's equipment is split, passively, to serve a group of customers. The group shares that capacity. On the common GPON standard, a split shares roughly 2.5 Gbps down and 1.25 Gbps up; newer XGS-PON shares about 10 Gbps in each direction. Carriers sell each customer a plan well below the shared total and count on everyone not peaking at once, which most of the time they do not.
The honest caveat
The speed on the quote is an "up to" figure. At the busiest hour in a busy building, you get what is left. Support is best effort, which in practice means a queue, and there is rarely an SLA with teeth. For a lot of businesses that is completely acceptable, and shared fiber is often the correct commercial decision. A 15-person office on a good shared fiber plan is usually better served than the same office on an oversized DIA circuit it cannot afford to back up.
See how we quote it on the shared fiber page.
Coax (cable)
Why the upload is small
Business cable runs over the same hybrid fiber-coax network as residential cable, using the DOCSIS standard. Capacity on a cable node is shared among the homes and businesses on it, and the system has traditionally given most of the spectrum to download. The result is a plan that can advertise a very large download figure with an upload that is a small fraction of it. Newer upgrades are raising upload speeds in some areas, so check the actual upload number on the quote rather than assuming.
Where coax earns its place
Two situations. The first is a very small office where the alternative is paying enterprise rates for capacity nobody uses. The second is more interesting: coax makes an excellent backup under a fiber primary, because it usually enters the building on a physically different path and runs on a different network. When your primary is cut, path diversity matters more than raw speed. We cover that design in Does your business need backup internet? and on our coax internet page.
A worked example
The numbers below are a hypothetical illustration, not a quote or a real client.
Say a 25-person accounting firm bills about $4,000 of staff time per working hour, runs its phones over the internet, and keeps client files in a cloud platform. If the connection drops, almost all billable work stops. One lost afternoon of four hours costs roughly $16,000 in time that cannot be recovered, before counting missed calls or a deadline slipping.
Now take a 6-person design studio that mostly works in local files and can tether to phones for a few hours. An outage is annoying and costs perhaps a few hundred dollars of friction.
The accounting firm should be on DIA, probably with a diverse backup underneath it. The studio would be spending money for no reason on anything more than good shared fiber, and possibly coax. Same city, same bandwidth needs on paper, very different right answers.
The decision, in one question
Ask what one hour of no internet costs your business. If the answer is "not much, we would go get coffee," shared fiber or coax is probably right. If the answer makes you wince, you want DIA with an SLA, and quite possibly a diverse backup under it.
The second question is upload. If you host, back up to the cloud during the day, or live on video calls, rule out anything with a thin upload no matter how good the download figure looks. Our guide to how much bandwidth your business needs walks through the arithmetic.
The most expensive mistake is not buying the wrong tier. It is buying the right tier from the only carrier you thought to ask.
What drives the cost of each
We do not publish prices, because the same product can cost very different amounts in two buildings a block apart. But the cost drivers are predictable:
- DIA is priced mainly by bandwidth, contract term and whether a carrier is already lit in your building. Construction to an unlit building can add a one-time charge or a longer term. Doubling the bandwidth usually costs well under double.
- Shared fiber is priced more like a plan: a set of speed tiers, often with a lower monthly cost and short terms, where the network already reaches the building.
- Coax is usually the lowest monthly cost of the three, with fast installs where the building is wired for cable.
The monthly number is not the whole cost of ownership. Add any installation or construction charge, the equipment you need at your end, a backup circuit if the primary is a single point of failure, and the cost of the outages the cheaper product allows. A DIA circuit that never goes down can be cheaper over a year than a shared line that fails twice at the wrong moment, and a shared line can be the far better buy for a business that shrugs off an afternoon offline. Why the same circuit costs different amounts in different buildings comes down to which carriers are already lit in your building.
Mistakes we see most often
- Comparing download numbers only. A "1 Gig" cable plan and a 500 Mbps DIA circuit are not the same class of product, and for business traffic the smaller number often performs better.
- Assuming "business" on the label means an SLA. Many business-branded plans are consumer infrastructure with a static IP and a different support line. Ask for the SLA document.
- Buying headroom for five years. On fiber, an upgrade is usually a configuration change. Buy what you need now and confirm how fast you can grow.
- One circuit, one path. A premium circuit is still a single point of failure if nothing sits under it.
Questions to ask your carrier
- Is this dedicated or shared at the access layer? If shared, what is the total capacity and how many customers share it?
- What are the upload and download speeds, separately?
- Is there a written SLA? Can I see the document, not the summary?
- Is your network already in my building, or does this require construction?
- How many static IPs are included, and what does a larger block cost?
- If I upgrade speed mid-term, is it a configuration change or a new install, and does it restart my term?
What we would tell you
We quote all three, and we will say plainly when the cheaper one is correct for your situation. A business that starts on shared fiber and upgrades to DIA in two years is a good outcome. A business sold a 10 Gbps circuit it will never fill is not.
Because several carriers bid on your address, you also see what each option really costs in your building, which is the only place the comparison means anything. The quote is free, carries no obligation, and you will usually hear back the same day. Send us your address, call 478-758-8091 or text (347) 870-0965, and see how pricing works on the pricing page.
