The data plane software creates RTOs for UDP and
TCP sessions and tracks state changes. It also synchronizes traffic
for IPv4 passthrough protocols such as Generic Routing Encapsulation
(GRE) and IPsec.
RTOs for synchronizing a session include:
Session creation RTOs on the first packet
Session deletion and ageout RTOs
Change-related RTOs, which include:
TCP state changes
Timeout synchronization request and response messages
RTOs for creating and deleting temporary openings in the
firewall (pinholes) and child session pinholes
