67
Table 13 lists each bridging and routing protocol and the technique you
must use to deal with the lack of connectivity in partially meshed and
nonmeshed Frame Relay and X.25 topologies.
Virtual Ports over PPP
PPP virtual ports differ from Frame Relay and X.25 virtual ports in the
following ways:
■ A PPP virtual port can potentially use any path in the dial pool.
Frame Relay and X.25 virtual ports are always associated with a
particular path.
■ PPP virtual ports operate independently and do not have a parent
port. No parent port exists because the path was unbound from its
port and placed into the dynamic dial path pool.
Frame Relay and X.25 virtual ports inherit the attributes of the path
over which they are defined.
■ PPP virtual ports can be used with dial-up related parameters.
Frame Relay and X.25 virtual ports cannot be used with dial-up related
parameters.
You can use virtual ports in a PPP environment to provide dial pooling at
the central site router. With dial pooling, a set of dynamic paths is
Table 13 Connectivity in Partially Meshed and Nonmeshed Topologies
Protocol Technique
Bridging Virtual port
Boundary Routing Virtual port
IP-RIP
*
* When configuring this protocol and another protocol that requires virtual ports over the same
path, use virtual ports.
Next-hop split horizon
IP-OSPF Virtual port
IPX
*
Next-hop split horizon
APPN
*
No special configuration if sending APPN only over Frame Relay
DECnet IV Virtual port
OSI/DECnet V No special configuration required
VINES Virtual port
XNS Virtual port
AppleTalk
*
Next-hop split horizon
