User manual
43
Directly connect terminal
：
connect the edge of network switch with terminal devices with
configuration
Edge port
，
which can achieve port state rapid conversion without the processing Discarding
，
Learning
，
Forwarding.
Don’t join RST structure
：
don‘t participate in RSTP running.
RSTP switch port states:
1.
Blocking
- A port that would cause a switching loop if it were active. No user data is sent or received over
a blocking port, but it may go into forwarding mode if the other links in use fail and the spanning tree
algorithm determines the port may transition to the forwarding state. BPDU data is still received in blocking
state. Prevents the use of looped paths.
2.
Listening
- The switch processes BPDUs and awaits possible new information that would cause it to
return to the blocking state. It does not populate the MAC address table and it does not forward frames.
3.
Learning
- While the port does not yet forward frames it does learn source addresses from frames
received and adds them to the filtering database (switching database). It populates the MAC Address table,
but does not forward frames.
4.
Forwarding
- A port receiving and sending data, normal operation. RSTP still monitors incoming BPDUs
that would indicate it should return to the blocking state to prevent a loop.
The example of Configuration: The priority of network bridge is ―32768‖
，
If there did not have network ID
less than itself, itself is root network bridge. There did not have same network ID in network. Every 2 seconds,
the network bridge will transmit BPDU message to all appoint port. If did not receive BPDU message more than
20 seconds, it realized port invalid, will calculate the status of network bridge again. Each status exchange for
each other if need to transmit, need to wait 15 seconds
5.7.3 Port trunking
In telecommunications, trunking is a method for a system to provide network access to many clients by
sharing a set of lines or frequencies instead of providing them individually. This is analogous to the structure of a
tree with one trunk and many branches. Trunking, is set by the configuration software, the two or more physical
ports get together into a logical path to increase the bandwidth between the switch and the network node.
Trunking is a packaging technology, it is a peer to peer link, both ends of the link are switches, it can be a switch
and a router, and also can be a host, switch or router. Based on port trunking function that allows between two or
more ports between switches, switches and routers, hosts the switch or router connected in parallel to provide for
the simultaneous transmission of higher bandwidth and greater throughput, significantly entire network capacity.
Trunking is more economical to increase the bandwidth between the switch and network device, such as servers,
routers, workstations, or other switches. Trunking function is to integrate more than one physical port (typically
2-4) to a logical channel.
（
Figure 5.7.21
）