0 ORIGIN ATTRIBUTETHE ORIGIN IS A MANDATORY ATTRIBUTE THAT DEFINES...
11.0 Origin Attribute
The origin is a mandatory attribute that defines the origin of the path
information. The origin attribute can assume three values:
IGP: Network Layer Reachability Information (NLRI) is interior to the
originating AS. This normally happens when we use the bgp network command
or when IGP is redistributed into BGP, then the origin of the path info
will be IGP. This is indicated with an “i” in the BGP table.
EGP: NLRI is learned via EGP (Exterior Gateway Protocol). This is
indicated with an “e” in the BGP table.
INCOMPLETE: NLRI is unknown or learned via some other means. This usually
occurs when we redistribute a static route into BGP and the origin of the
route will be incomplete. This is indicated with an “?” in the BGP table.
Example: