Which two characteristics apply to Cisco Catalyst 6500 Series Switch supervisor redundancy using NSF?

Which two characteristics apply to Cisco Catalyst 6500 Series Switch supervisor redundancy using NSF? (Choose two.)

A.
supported by RIPv2, OSPF, IS-IS, and EIGRP

B.
uses the FIB table

C.
supports IPv4 and IPv6 multicast

D.
prevents route flapping

E.
independent of SSO

F.
NSF combined with SSO enables supervisor engine load balancing

Explanation:
A key element of NSF is packet forwarding. In a Cisco networking device, packet forwarding
is provided by Cisco Express Forwarding (CEF). CEF maintains the FIB, and uses the FIB
information that was current at the time of the switchover to continue forwarding packets
during a switchover. This feature reduces traffic interruption during the switchover.
During normal NSF operation, CEF on the active supervisor engine synchronizes its current
FIB and adjacency databases with the FIB and adjacency databases on the redundant
supervisor engine. Upon switchover of the active supervisor engine, the redundant
supervisor engine initially has FIB and adjacency databases that are mirror images of those
that were current on the active supervisor engine. For platforms with intelligent modules, the
modules will maintain the current forwarding information over a switchover. For platforms
with forwarding engines, CEF will keep the forwarding engine on the redundant supervisor
engine current with changes that are sent to it by CEF on the active supervisor engine. The
modules or forwarding engines will be able to continue forwarding after a switchover as soon
as the interfaces and a data path are available.
As the routing protocols start to repopulate the RIB on a prefix-by-prefix basis, the updates
will cause prefix-by-prefix updates to CEF, which it uses to update the FIB and adjacency
databases. Existing and new entries will receive the new version (“epoch”) number,
indicating that they have been refreshed. The forwarding information is updated on the
modules or forwarding engine during convergence. The supervisor engine signals when the
RIB has converged. The software removes all FIB and adjacency entries that have an epoch

older than the current switchover epoch. The FIB now represents the newest routing protocol
forwarding information.