What is colocation?
Colocation is renting rack space in a data center with power, cooling and connectivity. We cover racks, U units, A/B power feeds and why operators colocate.
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Colocation means renting space for your own network and server hardware inside a data center, together with power, cooling, physical security and access to connectivity. The operator keeps ownership of its routers, switches and servers, while the data center supplies what that hardware needs to run reliably: redundant power, a controlled environment, security and the ability to set up cross-connects to other networks. For a network operator, colocation is the foundation of a physical presence in a given city or at a given IXP.
Racks and U units
The basic unit of colocation is a 19-inch rack (per the EIA-310 standard). Height is measured in U units (1U = 1.75 inches, or 44.45 mm); a typical rack is 42U or 48U. A customer can rent a single U, part of a rack, a full rack or a dedicated cage. When planning an install, what matters is the U units, the available power per rack and the equipment depth.
- A single U or shelf for one edge router or a few servers.
- Half a rack or a full 42U/48U rack for a larger network presence.
- A cage, a separated, enclosed space for bigger deployments.
- A power budget per rack (e.g. 3 to 6 kW) and a depth usually of 1000 to 1200 mm.
A/B power and cooling
Professional colocation provides redundant power in an A/B configuration: two independent power feeds, each with its own UPS and a PDU strip in the rack, fed from separate sources and backed by generators. Dual-power-supply equipment connects to both feeds, so the loss of one does not cause an outage. Reliability is described by Tier classes under the ANSI/TIA-942 standard (Tier III targets about 99.982% availability). Cooling keeps temperature and humidity within the ranges recommended by ASHRAE (the recommended range is about 18 to 27 °C), usually in a hot-aisle/cold-aisle layout.
Why operators colocate
Building your own data center with redundant power, cooling and security is expensive and rarely worthwhile. Colocation lets you place hardware in a carrier-neutral facility, close to other networks, and order cheap cross-connects instead of building long-haul circuits. That cuts latency, gives access to many transit providers and exchange points in one place, and provides a level of reliability that is hard to reach in an in-house server room. For an operator, colocation is also the natural place to build a PoP and join a local IXP.
Colocation and AS202520 SkyPass
AS202520 SkyPass runs its own PoPs in Warsaw and Wrocław, in carrier-neutral facilities with A/B power and presence at Polish IXPs (THINX, TPIX, WRIX, 1-IX). If you colocate hardware there, we can set up a cross-connect and deliver IP transit, peering or remote IXP access without you building your own presence in every city. For operators with no physical gear in our locations, we offer remote IXP access through our infrastructure.
Frequently asked questions
How is colocation different from renting a dedicated server?
In colocation you own the hardware and the data center provides only space, power, cooling and connectivity. With a dedicated server the hardware belongs to the provider, who also maintains it. Colocation gives full control over the hardware but requires you to buy and service it.
What does A/B power mean?
It means two independent power feeds (A and B), each with its own UPS and PDU strip, fed from separate sources and backed by generators. Dual-power-supply equipment connects to both feeds, so the failure of one does not cause an outage.
How much equipment fits in a 42U rack?
A 42U rack offers 42 U of vertical space, but the real density is limited by the available power per rack (often 3 to 6 kW) and the cooling capacity. High equipment density requires a rack with a higher power budget.
What is a carrier-neutral facility?
It is a data center not tied to a single operator, where many transit providers, networks and IXPs are present. It lets you freely choose providers and set up cross-connects to any of the networks present there.