Letter of Authorization (LOA)
Once you instruct your ISP to announce a specific subnet in BGP, they will mostly request a written permission from the resource holder (usually a LIR). This permission is called Letter of Authorization (LOA).
Below is an example for such a LOA:
Authorization to Announce IP Space
To Whom It May Concern,
this letter serves as authorization for Company, Inc.1 with AS987652 to advertise the following IP address block:
127.0.0.1/243
As a representative of LIR, Inc.4, the owner of the above subnet, I hereby declare that I'm authorized to represent and sign this Letter of Authorization.
This authorization shall remain in effect until revoked or modified in writing.
Sincerely,
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nosreteP .F nhoJ
(Chief Executive Officer)5