What is a cross-connect?
A cross-connect is a physical cable (fibre or copper) linking two racks inside a data center via the Meet-Me Room. We cover the MMR, media types and uses.
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A cross-connect is a physical, dedicated cable that links a port in one rack to a port in another rack inside the same data center, usually routed through the facility's Meet-Me Room (MMR). It is a layer-1 connection: a plain fibre-optic or copper cable running through the building's cable trays and the operator's patch panels. A cross-connect carries no network logic or routing of its own. It provides a clean, private path between two devices, over which you then run Ethernet, a BGP session, private peering (PNI) or an IP transit port.
The Meet-Me Room and the physical link
Cross-connects are built in the Meet-Me Room, a neutral patching space where the data-center operator joins links between customers. Your cable from the rack runs to a patch panel assigned to your space, and the facility operator patches a cord across to the other party's panel. For single-mode fibre, the typical in-building distances and loss budget sit well within the limits of standards such as 1000BASE-LX or 10GBASE-LR, so the insertion loss added by the cross-connect is negligible.
- Single-mode fibre (SMF, OS2) with LC/UPC or LC/APC connectors, for 1G, 10G, 100G and beyond.
- Multi-mode fibre (MMF, OM3/OM4) for short distances inside the same building.
- Twisted-pair copper (Cat6/Cat6a, RJ45) for 1GbE and 10GBASE-T links.
- Coaxial copper (E1/T1, DS3) in legacy telecom deployments.
- A patch cord cross-connected in the MMR by the facility operator, usually with its own order ID.
What a cross-connect is used for
A cross-connect is the basic building block of data-center connectivity. An operator uses one to connect its router to an IP transit provider's port, to the fabric switch of an internet exchange point (IXP), or directly to a partner's router for private peering (PNI). The same cable also reaches a CDN, a public cloud on-ramp or your own equipment in another rack. Unlike a metro backhaul circuit, a cross-connect stays inside a single building, so it is cheap, fast to provision and adds minimal, constant latency.
Ordering, cost and maintenance
You order a cross-connect from the data-center operator by stating the location of both racks, the media and connector type, and the technical contact for the other side (a LOA, or Letter of Authorization, confirms consent to patch into someone else's space). Billing is usually a monthly recurring charge per link, independent of the bandwidth used, plus a one-off installation fee. It is good practice to order cross-connects in pairs, routed over diverse cable paths, so that a single patching fault does not cut all of your connectivity.
Cross-connects in the AS202520 SkyPass network
AS202520 SkyPass has points of presence (PoPs) in Warsaw and Wroclaw, and physical cross-connects underpin every service we deliver: an IP transit port, private peering and backhaul to Polish IXPs including THINX, TPIX, WRIX and 1-IX. If you have your own rack in one of our facilities, you set up a BGP session with us over a single cross-connect. If you have no presence there, we offer remote IXP access, where we maintain the patching to the exchange switch and you receive a ready-to-use port.
Frequently asked questions
How is a cross-connect different from an ordinary fibre circuit?
A cross-connect is patching inside a single data center, usually through the Meet-Me Room, with constant and very low latency. A metro backhaul circuit runs between separate facilities and carries a much higher cost and latency.
Does a cross-connect have its own IP address or configuration?
No. A cross-connect is layer 1, just the cable and patching. IP addressing, VLANs and BGP sessions are configured on the equipment at each end of the link, not on the cross-connect itself.
What is a LOA when ordering a cross-connect?
A LOA (Letter of Authorization) is the document in which the owner of the target space or port consents to the facility operator patching into it. Without a LOA the data center will not build a connection into someone else's rack.
Is a cross-connect billed by bandwidth?
No. You usually pay a flat monthly fee for the link plus a one-off installation fee, regardless of whether you push 1 Mbit/s or 100 Gbit/s over it. The real limits are set by the optics and media you deploy.