All MBB types are supported for PCC-controlled LSP. The LSP MBB procedures for a
PCC-controlled LSP (path-computation-method pce and
pce-control disabled) are as follows.
MPLS submits a path request, including the updated path constraints, to the local
CSPF.
If the local CSPF returns a path, PCC signals the LSP with RSVP
control plane and moves traffic to the new MBB path.
If pce-report is enabled for this LSP, the PCC sends a
PCRpt message with the delegation bit clear to retain control and containing the
RRO and LSP object with the LSP identifiers TLV containing the LSP-ID of the new
MBB path. It includes the metric, LSPA, and bandwidth objects where the P-flag
is clear, which indicates the operational values of these parameters. Unless the
user disables the report-path-constraints option under the
pcc context, PCC also includes a second set of metric,
LSPA, and bandwidth objects with the P-flag set to convey to PCE the constraints
of the path.
If the CSPF returns no path or the RSVP-TE signaling of the
returned path fails, MPLS puts the LSP into retry mode and sends a request to
the local CSPF every retry-timer seconds and up to the value
of retry-count.
When pce-report is enabled for the LSP and the FRR Global
Revertive MBB is triggered following a bypass LSP activation by a PLR in the
network, PCC issues an updated PCRpt message with the new RRO reflecting the PLR
and RRO hops. PCE releases the bandwidth on the links that are no longer used by
the LSP path.