Enterasys csx400 Betriebsanweisung
IP Configuration Screen
Local Management User’s Guide
1-41
Enabling the RIP routing protocol allows IP Routing Services to build and maintain a dynamic
database of route information. The best routes learned by the RIP routing protocol are added to the
IP Forwarding Table to forward IP packets. The ability to switch the RIP routing protocol on and
off on a port-by-port basis provides great flexibility. On the same device, some router ports can be
running the RIP routing protocol while other router ports are not. If necessary, you can temporarily
disable the RIP routing protocol on any port without affecting the rest of your configuration.
database of route information. The best routes learned by the RIP routing protocol are added to the
IP Forwarding Table to forward IP packets. The ability to switch the RIP routing protocol on and
off on a port-by-port basis provides great flexibility. On the same device, some router ports can be
running the RIP routing protocol while other router ports are not. If necessary, you can temporarily
disable the RIP routing protocol on any port without affecting the rest of your configuration.
RIP-2
The following definitions compare and contrast some of the features of the RIP-1 and RIP-2
protocols.
protocols.
RIP-1 vs. RIP-2 —
A comparison of the features of RIP-1 and RIP-2 protocols (excerpted from
RFC 1722, and RFC 2080) follows:
RIP-2 is essentially an extension of RIP-1; it is not a new protocol. It is a superset of the
environments in which RIP-1 has been traditionally used. It should be noted that RIP-2 is not
intended to be a substitute for OSPF (Open Shortest Path First) protocol in large autonomous
systems. The restrictions on autonomous system diameter and complexity which applied to RIP-1
also apply to RIP-2.
environments in which RIP-1 has been traditionally used. It should be noted that RIP-2 is not
intended to be a substitute for OSPF (Open Shortest Path First) protocol in large autonomous
systems. The restrictions on autonomous system diameter and complexity which applied to RIP-1
also apply to RIP-2.
Subnet Masks —
RIP-2 allows the smaller, simpler, distance-vector protocol to be used in
environments that require authentication or the use of variable length subnet masks, but are not of
a size or complexity that requires the use of the larger, more complex link-state OSPF protocol.
a size or complexity that requires the use of the larger, more complex link-state OSPF protocol.
The original impetus behind the creation of RIP-2 was the desire to include subnet masks in the
routing information exchanged by RIP, as this was not included in the original definition of RIP. As
long as the subnet mask was fixed for a network, and well known by all the nodes on that network,
a heuristic could be used to determine if a route was a subnet route or a host route.
routing information exchanged by RIP, as this was not included in the original definition of RIP. As
long as the subnet mask was fixed for a network, and well known by all the nodes on that network,
a heuristic could be used to determine if a route was a subnet route or a host route.
The inclusion of the subnet mask in RIP-2 effectively creates a 64-bit address, which eliminates
the network, subnet, and host distinction. Therefore the inclusion of a subnet mask in RIP-2 allows
it to be used in an autonomous system which requires precise knowledge of the subnet mask for a
given route, but does not otherwise require OSPF protocol.
the network, subnet, and host distinction. Therefore the inclusion of a subnet mask in RIP-2 allows
it to be used in an autonomous system which requires precise knowledge of the subnet mask for a
given route, but does not otherwise require OSPF protocol.
Next Hop —
Entries in RIP-2 routing tables always have a Next Hop field. The Next Hop is the
IPv6address of the next router along the path to the destination. The purpose of the Next Hop in
the routing table is to prevent packets from being routed through extra hops in the system. The
limitation of a maximum network diameter of 15 hops for the Next Hop field is common to both
RIP-1 and RIP-2. This statement of the limit assumes that a cost of 1 is used for each network (see
Metrics, below).
the routing table is to prevent packets from being routed through extra hops in the system. The
limitation of a maximum network diameter of 15 hops for the Next Hop field is common to both
RIP-1 and RIP-2. This statement of the limit assumes that a cost of 1 is used for each network (see
Metrics, below).