Data Center Connectivity: Everything You Need to Know About Cross Connects

Despite being one of the most important components in a data center, connectivity options can be complex, confusing and hard to understand. There are numerous connectivity options and types including cross connects, dedicated and blended internet, cloud direct connects and interconnection.

In this article, we will breakdown the different types of internet connectivity and how it is used in the data center. We will define important cross connect terminology and industry abbreviations such as MMR, IXP and more.

What are cross connects? Why are they important?

What is a cross connect? In a data center environment, a cross connect is a physical direct connection between two different termination locations. For example, a cross connect can connect your colocation rack to a specific service provider such as an ISP, telecom carrier, network provider or cloud provider. Cross connect lines typically run above colocation racks in what is known as an overhead cable tray to a  Meet-Me Room (MMR) within a data center.

There are many reasons why cross connects are important. Unlike the public internet, cross connects are not susceptible to latency or congestion issues, they are more reliable and operate at consistently high speeds. Cross connects are also less expensive than connecting through conventional telecom networks for the bandwidth provided.

Internet and network connectivity

Cross connects are used to directly connect to specific internet and network connectivity providers within a data centers including AT&T, Verizon, CenturyLink, NTT, Zayo, Comcast Business, Spectrum and others. Most colocation providers and data centers are carrier-neutral which means that they have multiple on-net providers available to connect to within their data center.

Most colocation data centers have 12 or more options for ISPs, telecom carriers and network providers. Internet Exchanges (IX), also referred to as Internet Exchange Points (IXPs), are public and private data center facilities that offer a rich connectivity environment encompassing sometimes hundreds or even thousands of ISPs and telecom carrier networks.

In addition to being connected to the internet and telecom carrier networks, cross connects are also used to connect directly to a Cloud Service Provider (CSP) such as AWS, Microsoft Azure, Google Cloud and others. This is often referred to as a cloud direct connect. Not all data centers have cloud onramps. Therefore, they are not connected directly to the CSPs.

Cross connects are also used to connect to other data center facilities within a data center campus setting. This is referred to as an intracampus cross connect. They are used to connect your colocation racks in one data center to a campus of data centers. It works by connecting an aggregation point inside one data center to an aggregation point inside another data center. With intracampus cross connects, there’s no need for switching or routing. The connection speed is very fast as it is a private connection for moving data over short distances.

Access types and port speeds

There are many interconnect types, also known as access types, for cross connects in a data center environment. Colocation customers often have different requirements for their servers, storage devices, routers, switches, and related hardware. The most frequently available access types are COAX, fiber, copper, and POTS. There are also many flavors of these types. For example, fiber comes in single-mode and multimode. Copper comes in CAT5, CAT5E, CAT6, and CAT6A.

Along with the many different access types and options, port speed plays an important role in data center cross connects. It’s important that colocation customers make sure that their equipment is well suited for the port speed and or bandwidth they provision. It is important to note that there are minimum bandwidth commitment rates. The uplink and downlink speeds are symmetrical. Here are some examples.

  • 100M port- 10M to 100M or burst cap
  • 1G port – 10M to 1,000M or burst cap
  • 10G port – 500M to 10,000M or burst cap

In the examples above, colocation customers can pass traffic in excess of their committed rate, up to the burst cap rate. Traffic is charged by the port speed plus a premium for speeds above the minimum bandwidth commitment.

Cross connect pricing

Are there costs associated with cross connects? Most colocation providers charge a setup and monthly charge. The cost of a cross connect is determined by the type and port speed. Cross connects typically range in price from $100-$300 USD each per month. Some colocation providers offer free cross connects with the purchase of their colocation services.

Conclusion: We’re here to help with cross connects

Without cross connects, you cannot connect your servers, storage and networking hardware to the internet. This includes both dedicated internet access and blended internet provided by a colocation provider. Cross connects can be confusing. However, it is critical that you have a sound strategy when connecting your colocation environment to the internet, network or cloud provider.

GCG and Datacenters.com specialize in helping customers like you find colocation data center facilities to build their IT infrastructure globally. This includes finding on-net telecom carriers, ISPs, CSPs and network providers in our directory of 3,000 data center locations. Contact me to learn more about how I can help you design your network, streamline your search and fast track your provisioning.