Patch panels & labels
How to identify a cabling system so it is still readable when the person who installed it has gone. Covers the ANSI/TIA-606 identifier classes and what each level of the scheme names, the termination-field colour code, and a builder that assembles a compliant identifier from your own building, floor, room, rack and port.
A label that survives is worth more than a tidy rack.
One building, several telecom rooms
The normal case for a commercial building. The space identifier is floor plus a letter, so 3A is the first room on the third floor.
Not used by Class 2.
Not used by Class 2.
- 3A
- 3A.02
- 3A-B14
On the room door and in the records.
On the rack itself.
On the panel port AND on the faceplate at the far end — the same string in both places.
The link identifier is the one that matters. It is a single string naming one run, and it is printed at both ends — the port on the panel and the outlet in the wall. A scheme where the two ends carry different numbers is not a scheme; it is two sets of numbers and a tone set.
These identify what a field is, not what is patched into it — which is what lets you read an unfamiliar room from the doorway.
Orange — Demarcation point
Where the carrier's responsibility ends. Central-office terminations land here.
Green — Network connections
The customer side of the demarc, and auxiliary circuits provided by the carrier.
Purple — Common equipment
Switches, PBXs, multiplexers — the active kit the rest of the room feeds.
White — First-level backbone
Main cross-connect to intermediate cross-connect.
Grey — Second-level backbone
Intermediate cross-connect to horizontal cross-connect.
Blue — Horizontal cable
The runs out to work-area outlets. In most rooms this is the largest field by far.
Brown — Inter-building backbone
Campus cable arriving from another building.
Yellow — Auxiliary
Alarms, security, door control, and anything else that is not data or voice.
Red — Key telephone systems
Legacy key systems. Mostly of historical interest, and still present in older plant.
- What is ANSI/TIA-606?
- The administration standard for telecommunications infrastructure. It defines how spaces, pathways, cables, and terminations are identified, and how those identifiers are recorded, so that a cabling system can be worked on by somebody who did not install it.
- What do the colours on a cross-connect field mean?
- Blue is horizontal cable to the work area, purple is common equipment such as switches and PBXs, orange is the demarcation point, green is the customer side of the demarc, white and grey are first- and second-level backbone, brown is inter-building backbone, yellow is auxiliary and alarm circuits, and red is key telephone systems.
- How should I number patch panel ports?
- So that the same identifier appears at both ends of the run — on the panel port and on the faceplate at the outlet. The identifier should name the space, the panel, and the port, and it must match whatever is in the records. A scheme that only makes sense at one end is not a scheme.
- Are labels really worth the time?
- They are the difference between a five-minute move and a morning with a toner. Labelling is also the first thing dropped when a job runs late, which is exactly why so many rooms have to be re-toned from scratch a few years later.
The rest of the section
- 01RJ45 Wiring: T568A and T568BBoth colour codes, pin by pin, side by side.
- 02RJ11 Wiring and Phone PinoutsSix positions, three lines, two colour systems.
- 03Keystone Jack TerminationStrip, seat, punch, snap — without failing the certification.
- 0466 Block WiringFifty rows, four columns, and where the bridging clips go.
- 05110 Block WiringLay the pairs in, press the connecting block on.
- 06Cat5e vs Cat6 vs Cat6a vs Cat8Speed, distance, and power decide it — not the bigger number.
- 07Fibre Types, Connectors and PolishRead the jacket, read the connector, don't mate blue to green.
- 08Subnetting, ExplainedWhere the numbers come from, and the meaning behind them.
- 09PoE Standards and Why It Won't PowerThe switch reserves the class, not the draw.
- 10Camera Lens, Field of View and Pixel DensityCovering the room is not the same as identifying a face in it.
- 11Rack Planning: Units, Depth, Weight and HeatIt fits vertically. That was never the hard part.
- 12Writing a Switch ConfigurationFrom factory default to a switch you would hand over.
- 13Networking and Cabling GlossaryThe terms, and what they mean on a job.
We do this work
as well as document it
Anyone loading a panel, documenting a room, or inheriting a rack labelled in marker pen by somebody long gone.