Lancom Systems LCOS 3.50 User Manual
Page 70
LANCOM Reference Manual LCOS 3.50
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Chapter 7: Routing and WAN connections
70
Routing and
W
A
N
con
n
ections
Although the entries in the static routing table are set manually, this informa-
tion changes according to the connection status of the router and so do the
RIP packets transmitted.
̈
If the router has established a connection to a remote station, it propa-
gates all the networks which can be reached via this route in the RIPs with
the distance '1'. Other routers in the LAN are thus informed by these
means that a connection to the remote station has been established on
this router which they can use. The establishment of additional connec-
tions by routers with dial-up connections can be prevented, thus reducing
connection costs.
̈
If this router cannot establish a further connection to another remote sta-
tion, all other routes are propagated with the distance '16' in the RIPs. The
'16' stands for “This route is not available at the moment”. A router may
be prevented from establishing a connection in addition to the present
one may be due to one of the following causes:
୴
Another connection has already been established on all the other
channels (also via the LANCAPI).
୴
Y connections for the S
0
port have been explicitly excluded in the
interface table.
୴
The existing connection is using all B channels (channel bundling).
୴
The existing connection is a leased-line connection. Only a few ISDN
providers enable a dial-up connection to be established on the second
B channel in addition to a permanent connection on the first B chan-
nel.
Which information does the router take from received IP RIP packets?
When the router receives such IP RIP packets, it incorporates them in its
dynamic routing table, which looks something like this:
What do the entries mean?
IP address and network mask identify the destination network, the distance
shows the number of routers between the transmitter and receiver, the last
IP address
IP netmask
Time
Distance
Router
192.168.120.0
255.255.255.0
1
2
192.168.110.1
192.168.130.0
255.255.255.0
5
3
192.168.110.2
192.168.140.0
255.255.255.0
1
5
192.168.110.3