Cabletron Systems FRM User Manual - page 236
15-4
Frame Relay Module 4. 0 User G uide, Rev 01
Bridge Node Default Parameters
1
To assure correct operation of the spanning tree algorithm, follow these rules:
a.
Bri dge Max Age
must be less than or equal to twice the value of {
Bridge Forw ard
Delay
minus 1 second}.
b.
Bri dge Max Age
must be greater than or equal to twice the value of {
Bridge Hello
Ti me
plus 1 second}.
Bridge Enabled
enables bridging in the node, implementing the spanning tree algorithm.
If Bridging is disabled, all Bridge ports on the node will go into
Forwarding
state (described under "
Bridge Status Displays
" on page 19-21). No
BPDUs (see
Bridge Hello Time
below) will flow. No data will be bridged
except terminated LLC2 traffic.
Bridge Hello Time
is the frequency with which all bridges on the network will send "Hello" messages
(also called BPDUs, or Bridge Protocol Data Units) to adjacent bridges (the next ones
in all bridge paths) when the local bridge is "Root." Note that a root bridge is the one
with the lowest ID (which contains its
Bridge Priority
and MAC address) on the
network.
Bridge Max Age
determines how long Hello messages will remain valid when the local bridge is root
(described under "
Bridge Hello Time
").
Bridge Forward Delay
is the time the bridge will wait after entering
Listening
state before entering
Learning
state, or after entering
Learning
state before entering
Forwarding
state This delay is
intended to assure that the tree topology is stable before it is put into use.
The states are described under "
Bridge Status Displays
" on page 19-21.
Table 15-1 Bridge Node Default Parameters
Parameter
Valid Values
Default Value
Vi rtual LAN ID
n/a – accept the default
Bridge Enabled
Y/N
Y
Bridge Hello Ti me
1–10
(seconds)
1
2
Bridge Max Age
6–40
(seconds)
1
20
Bridge For ward Delay
4–30
(seconds)
1
15
Bridge Agi ng Ti mer
10–10000000
(seconds)
300
Bridge Priori ty
0–65535
32768
Max Size Bridge For warding Table
128–65535
32768
IP Bridging Enabled
Y/N
N
IPX Bridging Enabled
Y/N
N
SRB ID
0–f
(hex)
0
Defaul t Ethernet Frame Type
Type II, 802.3
Type II