Virtual Ports Over Frame Relay And X.25 - 3Com NETBuilder SI Using Manual

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ONFIGURATION OF ORTS AND

Virtual Ports over Frame Relay and X.25

Frame Relay and X.25 are peer-to-peer protocols that connect two nodes
on the network. Boundary Routing and bridging, Internet Protocol-Open
Shortest Path First (IP-OSPF), DECnet IV, VINES, and Xerox Network
Systems (XNS) require virtual ports because they do not provide a method
for dealing with Frame Relay or X.25 topologies where bridge/routers are
not directly connected to all others (full mesh). With Boundary Routing
system architecture, when you create a virtual port over a particular path,
each remote network attached to the Frame Relay or X.25 cloud is
treated as a separate network.
Internet Protocol-Routing Information Protocol (IP-RIP), Internetwork
Packet Exchange (IPX), DECnet V, and AppleTalk can operate over partially
meshed or nonmeshed Frame Relay or X.25 topologies without the use of
virtual ports.
The next-hop split horizon feature in IP-RIP, IPX, and AppleTalk RTMP
allows communication between bridge/routers that are not directly
connected to one another. To configure next-hop split horizon for these
routing protocols, you must have a list of neighbors, which can be
dynamically generated or manually configured in IP-RIP. Next-hop split
horizon is configured by adding static mappings to the address mapping
table.
You can configure dynamic neighbor learning for IPX using the CONTrol
parameter in the NRIP, SAP, and NLSP Services.
Although it is not necessary to define virtual ports on IP-RIP, IPX, or
AppleTalk routers in partially meshed or nonmeshed Frame Relay or X.25
topologies, virtual ports do provide the following additional benefits:
A virtual port can be defined for each configured neighbor, which
allows you to set up such features as filters and routing policies on a
per-neighbor basis.
Virtual ports provide easier control over your network, turning your
network into several point-to-point lines.
If you want your SuperStack II bridge/router to act as an Open System
Interconnection (OSI) router in a Frame Relay or X.25 topology, you do
not need to create virtual ports.
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