Nokia M11 T66220, Руководство пользователя

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Nokia M11 User’s Manual
E
Copyright Nokia Networks Oy C33833001SE_00 6-2
6.3 Routing and bridging
Nokia M11 functions as a brouter, which means that it acts as a
network router for TCP/IP traffic and as a network bridge for
non-routable traffic.
6.3.1 TCP/IP routing
As a router, Nokia M11 keeps track of the networks that are accessible
through each network interface. If you have configured your M11 to
use the Routing Information Protocol (RIPv1 or RIPv2), M11
exchanges information with other routers to learn about the best routes
to remote networks and to advertise the networks for which M11 has
the appropriate route.
When M11 receives a TCP/IP packet, it looks up the network portion
of the packet’s destination IP address in its routing table and then
forwards the packet through the network interface that will let the
packet reach its destination most efficiently.
6.3.2 Static and dynamic routes
Static routes identify pathways to destination networks that are stable
over time or to networks that must always be available, even if a link is
not currently open. These static routes let each router recognise how to
reach the other, even if one router has not heard from the other recently.
Dynamic routes identify pathways to destination networks that may
change over time. Dynamic routes are created and configured when
routers broadcast RIP (Routing information protocol) packets,
advertising the networks they can reach and the distance (number of
routers) to each network.
6.3.3 Bridging
Nokia M11 can function as an Ethernet bridge. It can bridge all
protocols or all non-routable (non-IP) protocols between all of its
interfaces. The user just has to specify which interfaces take part in the
bridging function. The bridging function automatically learns the
MAC addresses located behind each of its active interfaces and uses
this information to filter local traffic at an interface to prevent it from
being unnecessarily relayed to other interfaces. For that purpose, M11
has a 256-slot MAC address table where it keeps these learned