Once your equipment is in a data center, its value depends on what it connects to. Interconnection is how it reaches carriers, internet exchanges, partners, customers and your other data centers. Some of those connections are a cable across the building. Others are wavelengths or fiber running between cities.
This page covers the three parts of data center interconnection: cross-connects inside a facility, interconnection fabrics and peering, and data center interconnect (DCI) links between your own sites. At ITBroker.com we help businesses plan and buy these connections. We are paid the same whichever provider you choose, so our job is to find the fit, not to push a product.
What Is Data Center Interconnection?
Data center interconnection is the set of private connections that link your equipment in a data center to other networks and to your other facilities. It has three parts:
- Cross-connects. A cross-connect is a dedicated cable, fiber or copper, that the data center runs between your cage or rack and another party in the same building: a carrier, a partner, a customer or a cloud provider. Cross-connects usually pass through the facility’s meet-me room (MMR).
- Exchanges, fabrics and peering. An internet exchange point (IXP) lets you exchange traffic with many networks over one port. A software-defined interconnection fabric lets you create virtual connections to other companies on the fabric, in the same building or in other markets, without ordering a new cable each time. Peering is the agreement to swap traffic directly with another network instead of paying a transit provider to carry it.
- Data center interconnect (DCI). DCI is the set of links between your own data centers, or between a data center and a large office. It is usually built with wavelengths, dark fiber or Ethernet services.
These connections are what make a carrier-neutral data center or carrier hotel valuable. The more networks present in the building, the more choice you have and the shorter your paths.
Why Choose Data Center Interconnection?
Core Problems Data Center Interconnection Solves
- Long, costly paths to partners. Without interconnection, traffic to a carrier, payment processor or trading partner may leave the building, cross the internet and come back. A cross-connect turns that into a few meters of fiber with predictable latency.
- Paying for traffic you could exchange directly. Every gigabit sent through an IP transit provider costs money. Peering with the networks that receive most of your traffic, directly or at an exchange, can take a share of that traffic off your transit bill and shorten the path to those users.
- Keeping two data centers in sync. Replication, backup, clustered databases and storage mirroring need high-capacity, low-latency links between sites. DCI provides private bandwidth sized for that load.
- Single-carrier dependence. Being able to cross-connect to several carriers in one building makes it easier to build redundant paths and to switch providers at renewal.
Who Should Consider Data Center Interconnection?
- Companies with equipment in colocation that need to reach carriers, partners or customers
- Networks, hosting companies, SaaS providers and content companies sending large amounts of traffic to the internet
- Businesses running two or more data centers for capacity or disaster recovery
- Financial, media and healthcare firms that exchange data with specific partners on a schedule or in real time
Facing this decision now? We’ll tell you where you stand.
No pitch. No prep. Just answers. We're paid the same whichever vendor you choose.
Key Features of Data Center Interconnection
| Feature | What to Know |
|---|
| Cross-Connect Types | Single-mode fiber is most common; multimode and copper are used for short runs. Each is ordered and billed separately |
| In-Building and Campus Reach | Cross-connects can run within one building or between buildings on the same campus, often at a higher fee |
| Exchange Ports | IXP ports are usually sold at 1, 10 or 100 Gbps, with higher speeds at the largest exchanges; one port can reach every network peering there |
| Virtual Connections | Fabric platforms let you turn up connections to other members in minutes and change their speed in software |
| DCI Capacity | Wavelengths commonly from 10 Gbps to 400 Gbps; dark fiber lets you light your own capacity with your own optical gear |
| Layer 2 or Layer 3 | DCI can extend Ethernet networks between sites (Layer 2) or connect them as routed networks (Layer 3) |
| Diversity | Separate entrances, conduits and fiber routes so one cut doesn’t take down both links |
DCI: Linking Your Own Data Centers
The right DCI option depends mostly on distance, capacity and how much of the network you want to run yourself:
| Option | How It Works | Best Fit |
|---|
| Wavelength | A carrier carries a dedicated optical channel between your sites over its DWDM network | High, steady bandwidth between metros or regions without owning optical equipment |
| Dark Fiber | You lease unlit fiber strands and add your own optics | Very high or growing capacity within a metro, full control, long terms |
| Ethernet (Carrier Ethernet or private networking) | A carrier delivers a point-to-point or multipoint Ethernet service | Moderate bandwidth, more than two sites, or a managed service |
Many companies combine options, such as dark fiber between two data centers in one metro and wavelengths to a disaster recovery site in another region. Whatever you choose, the second path should take a physically different route; see path diversity.
Implementation Insights
- Map the traffic. List who you need to reach (carriers, exchanges, partners, other sites) and how much traffic flows to each.
- Choose the facilities. Where you connect depends on who is in the building. Check which carriers, exchanges and fabrics are present before committing to space.
- Order cross-connects. The other party usually issues a letter of authorization (LOA) naming their port; the data center then runs the cable. Track every cross-connect so you can cancel unused ones.
- Set up peering. Join an exchange or arrange private peering, then configure BGP sessions and routing policies.
- Build and test DCI. Order diverse paths, confirm the routes on fiber maps, and test failover before production traffic depends on it.
Data Center Interconnection vs. Cloud Connect
Private links into public clouds, such as AWS Direct Connect, Azure ExpressRoute and Google Cloud Interconnect, are covered on our Cloud Connect page. They often use the same facilities and cross-connects described here, but have their own ports, pricing and redundancy rules.
Peering vs. IP Transit
IP transit is a paid service that carries your traffic to the whole internet. Peering exchanges traffic only between two networks and their customers. Most networks use both: peering for the networks they exchange the most traffic with, and transit for everything else.
Data Center Interconnection vs. Private Networking
Private networking links your offices, branches and data centers as one managed network, usually MPLS or carrier Ethernet. This page is narrower. It covers cross-connects, exchange fabrics and peering inside a facility, plus data center interconnect (DCI): the dedicated links between your own data centers. A private network often reaches your data center through a cross-connect, and some companies run DCI traffic over their private network, so most businesses with equipment in colocation use both.
Data Center Interconnection vs. Colocation
Colocation is the space, power and cooling for your equipment. Interconnection is what connects that equipment to everything else. The two are usually bought from the same operator, but cross-connect fees are a separate and growing line on the bill.
Common Challenges and Misconceptions About Data Center Interconnection
- “Cross-connects are a minor cost.”
Each one carries a one-time fee and a monthly fee for as long as it exists. Over a multi-year term, cross-connects can add up to a large share of the colocation bill, and fees for the same cable vary widely between operators.
- “Two links means redundancy.”
Two circuits from different carriers can still share a conduit, a bridge or a building entrance. Ask for route maps.
- “Peering is only for large networks.”
Any company with its own IP addresses and an autonomous system number can peer. Whether it is worth it depends on how much traffic goes to the networks at the exchange.
- Forgetting old cross-connects.
Unused cross-connects stay on the bill until someone cancels them. An audit often finds savings.
How to Choose the Right Data Center Interconnection Partner
- Who is in the building. Count the carriers, exchanges, fabrics and partners you can reach from each facility.
- Cross-connect pricing. Get one-time and monthly fees in writing, and negotiate them as part of the colocation contract rather than later.
- Campus and metro reach. Can you reach other buildings on the campus, or other data centers in the metro, without a separate carrier?
- DCI options. Which carriers offer wavelengths, dark fiber or Ethernet between your sites, and over what routes?
- Diversity proof. Ask for fiber route maps and entrance details, not just promises.
- Provisioning time. Find out how long cross-connects, exchange ports and DCI circuits take to deliver.
Data Center Interconnection Pricing Models
| Cost | How It’s Charged | Notes |
|---|
| Cross-Connect | One-time install fee plus a monthly fee per cable | Usually set by the data center operator; negotiable at signing |
| Exchange or Fabric Port | Monthly fee by port speed | Fabrics may add a monthly fee per virtual connection |
| Peering | Usually no fee between the two networks | You still pay for the port and cross-connect |
| Wavelength | Monthly fee by capacity, distance and term | Install fees and lead times rise if construction is needed |
| Dark Fiber | Long-term lease or upfront purchase plus annual maintenance | You also buy and run the optical equipment |
| Ethernet | Monthly fee by bandwidth, distance and term | Often the simplest managed option |
Prices vary widely by market, facility and term, so compare the full cost of each design over the life of the contract.
We work on the buyer’s side, and we are paid the same whichever provider you choose. Our process:
- Discovery Call
We learn where your equipment is, who you need to reach, and how much traffic moves between your sites.
- Facility and Route Review
We check which carriers, exchanges and fabrics are present in each building and which routes connect your sites.
- Market Quotes
We collect quotes for cross-connects, ports and DCI circuits from operators and carriers and compare them on total cost.
- Negotiation
We negotiate fees, terms and diversity, including cross-connect pricing at colocation signing.
- Ordering and Turn-Up
We coordinate LOAs and installs and stay involved after the connections are live.
FAQs About Data Center Interconnection
Q: What is the difference between a cross-connect and a data center interconnect?
A: A cross-connect is a cable inside one facility between you and another party. A data center interconnect links two separate facilities, usually over a carrier’s wavelength or Ethernet service or over dark fiber.
Q: Do I need to be in the same building as my partner?
A: For a cross-connect, yes, or on the same campus. Otherwise, an interconnection fabric, a carrier circuit or a DCI link can reach them in another facility.
Q: How much does a cross-connect cost?
A: It depends on the operator, market and cable type. Expect a one-time install fee and a recurring monthly fee for each cross-connect, and negotiate them up front.
Q: Should I peer or buy transit?
A: Most networks do both. Peering makes sense for the networks you exchange a lot of traffic with; transit covers everyone else.
Q: Wavelength or dark fiber between my data centers?
A: Wavelengths suit long distances and companies that don’t want to run optical equipment. Dark fiber suits short metro routes with high or growing capacity needs and a team that can operate it.
Facing this decision now? We’ll tell you where you stand.
No pitch. No prep. Just answers. We're paid the same whichever vendor you choose.
