[CAUSE] The vRtrLdpSessionStateChange notification is generated when an Overload Notification is sent to or received from the peer vRtrLdpPeerLdpId for a fec type of vRtrLdpSessOverloadFecType when vRtrLdpSessState remains 'operational'. [EFFECT] Once the Local LSR has sent the Overload Notification to the peer vRtrLdpPeerLdpId for the fec type of vRtrLdpSessOverloadFecType and vRtrLdpSessOverloadState has the value of 'true', then new Label Mapping Messages received from the peer vRtrLdpPeerLdpId for the fec type of vRtrLdpSessOverloadFecType is returned with a Label Release Message. If the Local LSR has received an Overload Notification from the peer vRtrLdpPeerLdpId for the fec type of vRtrLdpSessOverloadFecType and vRtrLdpSessOverloadState has the value of 'true', no new Label Mapping Message for the fec type of vRtrLdpSessOverloadFecType will be sent to the peer vRtrLdpPeerLdpId. If the Local LSR has received an Overload Notification from the peer vRtrLdpPeerLdpId for the fec type of vRtrLdpSessOverloadFecType and vRtrLdpSessOverloadState has the value of 'false', then the Local LSR will send all pending and any new Label Mapping Message for the fec type of vRtrLdpSessOverloadFecType to the peer vRtrLdpPeerLdpId. [RECOVERY] In case the Local LSR sent the Overload Notification to the peer vRtrLdpPeerLdpId and vRtrLdpSessOverloadState has the value of 'true' for fec type vRtrLdpSessOverloadFecType, then appropriate LDP configuration changes may be required on the Local and/or Remote LSR. Once the Local LSR is not overloaded anymore, an Overload Notification is sent to the peer vRtrLdpPeerLdpId and vRtrLdpSessOverloadState has the value of 'false' for fec type vRtrLdpSessOverloadFecType. This notification was obsoleted in release 13.0.