Demarc Extension Diagrams
A demarc extension is defined as:
The transmission path originating from the interface of the access provider’s side of a telecommunications circuit Demarcation Point within a premise and ending at the termination point prior to the interface of the edge Customer Premises Equipment. This may include in-segment equipment, media converters and patch cords as required to complete the circuit’s transmission path to the edge CPE.
The following diagrams show the various configurations that may occur when extending a circuit’s demarcation point. These diagrams and terminology will accelerate fault isolation and communications between parties when a demarc extension is suspect for circuit issues.
It is recommended to test from the interface side of the access provider’s demarcation point to isolate the telecom circuit from the demarc extension. For details about specific items, please refer to our Terminology section.
Single Segment Demarc Extension Diagrams
Direct Connect / Direct Connect
Indirect Connect / Indirect Connect
Direct Connect / Indirect Connect
Indirect Connect / Indirect Connect
Indirect Connect / Direct Connect
Multi-Segment Demarc Extension Diagrams
Direct Connect / Direct Connect
Indirect Connect / Indirect Connect
Additional Demarc Extension Diagrams
In some instances, the circuit is delivered outside of the facility and will require a MPOP Extension in addition to the demarc extension.
The Demarc Pre-Wire is not interfaced into the local access providers’s side of the Demarcation Point and thus is not a demarc extension.
Patch Cord Testing
A demarc extension by definition is a complete channel, which can include patch cords or cross connects. However due to installer responsibilities, patch cords may be the requirement of another party and must be noted upon testing of the demarc extension by:
- Tested with patch cord
- Tested without patch cord
This will provide accelerated fault isolation if the circuit is not working properly upon another party supplying patch cords at circuit turn up.
Additional Information
Specified connections for a demarc extension will fall into one of four types and will vary on a case-by-case basis:
- Direct/Direct
The demarc extension is directly connected to both the Demarcation Point and the eCPE without the use of additional connections such as patch cords. - Indirect/Indirect
The demarc extension requires additional connections such as patch cords to interface with the Demarcation Point and the eCPE. - Direct/Indirect
The demarc extension is directly connected to the Demarcation Point, however requires additional connections such as a patch cord to interface with the eCPE. - Indirect/Direct
The demarc extension requires additional connections such as a patch cord to interface with the Demarcation Point, however it is directly connected to the eCPE.