This is an original planning guide. It is not a vendor manual, an official standard, or legal advice. Example addresses use documentation ranges. Review every command before you paste it.
What this hour is for
A link budget adds the transmitter, the antenna gain, and the losses, then subtracts the path. Free-space loss grows with distance and frequency. EIRP is the power you must keep legal. The calculators draft the arithmetic. They do not license the link.
Use a path you have permission to use. A rooftop-to-rooftop guess across property you do not control is not a plan you execute. Regulatory power is a ceiling.
Rain fade and Fresnel clearance belong to the point-to-point page when the path is long. This page is the budget for one hop you can describe.
Documentation addresses are irrelevant here. The names that matter are the two ends and the frequency.
The change you can finish
Apply nothing during the writing of the note. When the lab window opens, it is one change on the device named in the ticket. Read the draft, then the device, then decide.
Rollback is the file or the revision you saved first. You do not invent a rollback after the only copy is gone.
- Name the two ends you may use.
- Compute the budget.
- Write the EIRP against the limit.
- If the margin is thin, stop and redesign.
- Do not aim at a path you do not control.
- Do not raise power past the limit.
Mistakes that outlive the command
RF Link Budget Explained goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.
- A path across property you do not control.
- EIRP over the limit.
- A calculator result treated as a license.
- Two hops designed as one.
Decisions to write down
One decision for RF Link Budget Explained: Both ends are permitted. EIRP is within the limit. The margin is written. A thin margin stops the work. And this is not a license.
Checks before you call it done
Confirm this before you call the change done: The ends are named. The budget is in the note. The limit is cited. Power was not raised past it. And no unauthorized path was aimed. If one of those fails, stop.
Before you leave the device
RF Link Budget Explained ends when the hostname on the device matches the hostname in the ticket. If it does not, you are on the wrong box. Stop. A command that succeeded on the wrong box is not progress.
The draft stays a draft until a person has read the names in it. A generator does not log into the device and does not know which interface is the uplink. You delete a line that names a device, a zone, or a prefix you did not write down.
0.0.0.0/0 is not kept because a sample included it. A source you can say is the source you keep. 192.0.2.0/24, 198.51.100.0/24, 203.0.113.0/24, and 2001:db8::/32 are documentation. They belong in the note. They are not prefixes you type onto a production device because they appeared in a draft.
prompt-for-this is a reminder that a secret is missing. It is not a password, a key, a community string, or a pre-shared key you save in the ticket or in git. The real secret stays in the store.
One change is the window. A VLAN and a routing protocol and a VPN do not share it. If two things move and the result is wrong, you will not know which one did it. The next feature waits for its own page.
If the same step fails twice, stop for the day. The failure is the result. Adding a forum command beside a half-applied config produces a device nobody can rebuild. Restore the copy you took first.
A second person reads the device name and the change aloud. If they cannot find them in the ticket, the note is not done. Silence is not agreement. Then leave the device alone.
This page is a planning guide. It is not a vendor manual, not an official standard, and not a permission to touch a network you do not administer. The pillar guide owns the wider design. This page owns one lab proof.
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