Fujitsu PRIMERGY 10/40GbE Connection Blade 18/8+2 Parts list manual

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PRIMERGY
PRIMERGY 10/40GbE Connection Blade 18/8+2
Function Manual
FUJITSU

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Chapter 1 Network design concepts .......................................................................................................... 3
1.1 Layer 2 network design concepts .................................................................................................. 3
1.1.1 VLAN .................................................................................................................................... 3
1.1.2 Link aggregation .................................................................................................................. 4
1.2 Outline of Device Setting .............................................................................................................. 4
Chapter 2 Outline of functions .................................................................................................................. 5
2.1 Auto negotiation function............................................................................................................. 5
2.2 Flow control function.................................................................................................................... 6
2.3 Forwarding mode change function................................................................................................ 7
2.4 MAC address learning / MAC forwarding function ........................................................................... 8
2.5 VLAN function .............................................................................................................................. 9
2.6 Link aggregation function .......................................................................................................... 13
2.6.1 LACP Function ..................................................................................................................... 14
2.7 Back-up port function ................................................................................................................. 15
2.8STP Function .............................................................................................................................. 16
2.8.1 STP..................................................................................................................................... 16
2.8.2 RSTP................................................................................................................................... 19
2.8.3 MSTP .................................................................................................................................. 20
2.9 LLDP function ............................................................................................................................ 21
2.10 MAC filtering function................................................................................................................. 22
2.11 QoS function .............................................................................................................................. 25
2.11.1 Priority control function....................................................................................................... 25
2.11.2 Priority control function where in ACL is used ....................................................................... 28
2.12 IGMP snoop function .................................................................................................................. 31
2.13 MLD Snoop Function .................................................................................................................. 33
2.14 EHM Function ............................................................................................................................ 35
2.15 IEEE802.1X Authentication Function ........................................................................................... 36
2.16 Guest VLAN function................................................................................................................... 41
2.17 Broadcast / Multicast storm control function ................................................................................ 42
2.18 Port mirroring function ............................................................................................................... 43
2.19 Ether L3 Monitoring Functions .................................................................................................... 45
2.20 Output rate control function ....................................................................................................... 46
2.21 Port block function ..................................................................................................................... 47
2.22 IP route control function ............................................................................................................. 48
2.22.1 Types of IP route information............................................................................................... 48
2.22.2 Management of IP Route Information .................................................................................. 49
2.22.3 Route Control Function according to the Error Detection of Interface...................................... 49
2.22.4 Static Routing Function ....................................................................................................... 49
2.23 IPv6 Function ............................................................................................................................. 50
2.24 IP Filtering function.................................................................................................................... 54
2.25 DSCP Value Rewrite Function....................................................................................................... 55
2.26 RADIUS function......................................................................................................................... 57
2.27 SNMP Function........................................................................................................................... 59
2.27.1 RMON Function................................................................................................................... 60
2.28 SSH server function .................................................................................................................... 61
2.28.1 SSH client software ............................................................................................................. 63
2.29 Application Filter Function.......................................................................................................... 64
2.30 TACACS+ Function....................................................................................................................... 65
2.31 LDAP Function............................................................................................................................ 66
2.32 IEEE802.1Q Tunneling Function .................................................................................................. 67
2.33 CEE Function .............................................................................................................................. 69
2.34 Edge virtual switch function........................................................................................................ 71

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Chapter 1 Network design concepts
1.1 Layer 2 network design concepts
1.1.1 VLAN
In layer 2 network, the destination is determined based on MAC address. And Layer2 network can be divided by
logical network called VLAN. It can make one logical network from multiple physical network or multiple logical
network from one physical network. Each VLAN is managed with VLAN ID(VID).
VLAN ID
VLAN is managed by VLAN ID which number is from 1 to 4094 in decimal. The communication between the
same VLAN ID is possible but between the different VLAN ID is not possible.
Type of VLAN
There are three type of VLAN.
• Port VLAN
This is to set “which vlan is belonged“ to each Ethernet port. The port will belong to assigned VLAN
• Tag VLAN
It is used when multiple VLANs are set on 1 physical line. Multiple VLANs are implemented on 1 physical line by
inserting VLAN header in the frame header of Ethernet by the method standardized in IEEE802.1Q.
• Protocol VLAN
In the frame header of Ethernet, there is a field of 16 bits called as frame type, and upper level protocol which
is stored in that frame can be identified.
For example, communication of different network protocol called as IP and IPX can be identified at the level of
the Ethernet frame. VLAN protocol uses this information and VLAN different in each network protocol can be
identified.
For example, VLAN for each sub network is divided and routing is executed in IP. However, in the IPX protocol
setting is executed where it is treated as 1 network without any divisions.
The setting of each ETHER port can be changed for these three types. In other words, when VLAN ID is 10, VLAN
can be set as VLAN port in ETHER port 1, and tag VLAN in ETHER port 2. The data of 10 VLAN is sent and
received by ETHER port 1 and ETHER port 2, and it is sent and received as a normal frame without tag by ETHER
port 1 and the frame with tag by ETHER port 2 in VLAN ID.
Router
Port VLAN
（VID10）
Port VLAN
（VID20）
Port VLAN
（VID30）
Tag VLAN
（VID10,20,30）
Router
Port VLAN
（VID10）
Protocol VLAN
（FNA VID20、IP VID30）

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1.1.2 Link aggregation
Link aggregation is a technology which treats 1 logical circuit by collecting physical circuit together. When
there is insufficient area in one physical circuit, wide area is secured by collecting multiple circuits together.
Moreover, when one circuit cannot communicate due to the cause of the failure etc. among physical circuits
which set link aggregation, the function of a redundant composition is also provided because the
communication can be continued with the other physical circuit.
When two or more VLAN are included, it is the structure where multiple VLAN are included in one circuit
logically, is composed of link aggregation similar to 1 physical circuit. Moreover, even STP is treated as one
circuit and the control of the port is executed by logical circuit of link aggregation.
1.2 Outline of Device Setting
Relation of network and setting
As the information to be set in this device, Physical information related to circuit connection, logical
information related to network connection and routing information in sorting condition of data is required.
Moreover, other device specific information and setting of additional services are executed when required. In
this device, large scale classification related to setting of this information is as follows.
•ether definition
It is an instruction group defining physical information related to connection circuit in this device. Information
related to type and speed of circuit is defined.
•vlan definition
It is an instruction group defining information related to VLAN of this device. Information of VLAN protocol and
information of static study table are defined.
•lan definition
It is an instruction group defining logical information related to LAN connection in this device. Information of IP
address of LAN and network is defined. Moreover, it is defined according to lan definition related to LAN
dependent service of DHCP etc.
•Other definitions
It is an instruction group defining necessary information depending on device and information of additional
services. Information related to network administration and time information is also defined.
Definition of Network Interface
The network interface which acts as ‘exit’at the time of data transmission, has various types according to its
characteristics and connected circuit. Following is the explanation for types of network interface.
•lo
Loopback interface. It is used when return transmission is executed by internal program of the device.
•lan
Ethernet interface. It is an interface that is used in case of transmission used by Ethernet. It is set according to
the lan definition. The interface number given to this interface type, becomes the network interface name.
Example：lo0,lan0,lan1,…
Network interface of lan is set according to the lan definition.
Definition number of lan definition and interface number of network interface are in 1 to 1 correspondence.
Definition of Routing Information
Routing information defines the information necessary to determine the network interface that finally
becomes the exit. In this device, routing information is set within the definition in exit interface. For example,
routing information that is defined in lan0 for output from lan0 and routing information that is defined in
lan1 for output from lan1 are set separately.

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Chapter 2 Outline of functions
2.1 Auto negotiation function
The auto negotiation function is the protocol between two devices provided by IEEE802.3u, and is the function
to set the transmission speed and the communication mode (full duplex/half duplex) automatically according to
the priority level.
▪Communication mode is set according to algorithm determined from modes which can be communicated
mutually for connections between similar auto negotiation (Auto-Nego).
▪When fixed config is used, normal communication is possible only in case of similar communication mode.
Points to be noted
▪When one side is connected with the auto negotiation, and the other side is connected with fixed FULL (full
duplex), the communication mode is recognized as HALF (half duplex). In such cases, due to high error rate,
normal communication may not be possible. Hence set the communication mode correctly.
▪Set both side communicate modes firmly when the communication mode of one side or both sides cannot be
recognized mutually in auto negotiation.
▪When one side is connected improperly at fixed 10M, and other side at fixed 100M, the link is established with
only one device, and as per the communication state, the connection with the link can be established or cut off
repeatedly. In this case, set the communication mode correctly.
▪There is no auto-negotiation function for link speed in 10G port.

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2.2 Flow control function
In this device, the flow control function is supported by Pause frame based on IEEE802.3x. As per the flow
control settings, operation of each port is as shown below.
Points to be noted
When the flow control is applied, the connected side might not be able to transmit the frame to corresponding
port of this device. In this case, frame may be discarded as per the buffer capacity of connected side irrespective
of the priority of priority function that is set in this device. For that, disable the flow control for the network
where voice or image is used. In addition, transfer performance of data frame may deteriorate depending on
the connected side. Whether the PAUSE frame must be transmitted by flow control, is decided as per the
remaining capacity of the received buffer of input port. The frame transferred to port that is being controlled by
the length of output queue with ‘buffermode qos’or ‘ratecontrol’, is discarded in output queue side, therefore it
is not accumulated in the reception buffer of input port. As a result, regardless of the frame being disregarded,
‘Pause’ frame is not transmitted. In order to execute the flow control steadily, set the buffermode to max so
that it is not transfered to the port where the ratecontrol is set.
<In case of fixed mode>
1) Ignored when Pause frame is received.
Flow control setting
Communication
mode
System operation
Transmission
Reception
Transmission direction
Reception direction
Off setting
Off setting
Full double fixed
Pause frame not transmitted
Flow control is not executed when
Pause frame is received (1)
On setting
Off setting
Full double fixed
Pause frame is transmitted for
flow control.
Flow control is not executed when
Pause frame is received (1)
Off setting
Off setting
Full double fixed
Pause frame not transmitted
Flow control is executed Pause frame is
received
On setting
Off setting
Full double fixed
Pause frame is transmitted for
flow control.
Flow control is not executed when
Pause frame is received (1)

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2.3 Forwarding mode change function
In this device, cut-through mode and store-and-forward mode can be selected as a switching method.
Cut-through mode
Top portion of the packet is input to this device and then the packet is delivered from the transfer destination
port. Transfer is executed without waiting for the entire packet to be input, therefore delay of the packets
associated with transfer can be minimized.
Store-and-forward mode
Entire packet is input to this device and then the packet is delivered from the transfer destination port.
Points to be noted
When cut-through mode is selected, latency is can be reduced and error packets are relayed. In case of
store-and-forward mode, error packet is not transited even if it is input. On the other hand, latency is
lengthened than the cut through mode due to accumulation of packet data.

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2.4 MAC address learning / MAC forwarding function
In this device, following functions are supported as a MAC address learning function.
MAC address learning basic function
It is a function that dynamically learns the transmission source MAC address of reception packet
and registers it in FDB (Forwarding Data Base). The registered MAC address is retained and
continued till aging-out time. Aging-out time can be changed by structure definition command.
(default is 300 seconds). When port is linked down, an entry learned from the corresponding
port on FDB is deleted.
MAC address auto study stop function
It is a function to stop the learning of dynamic MAC address in device unit according to structure definition.
FDB clear function
It is a function to delete the dynamically studied FDB entries. Conditions like Port unit, MAC address unit etc
can be specified.
Static MAC forwarding function
It is function where the frame having specific destination address can be transited to the port specified at each
VLAN. Unicast address can be specified in destination address.

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2.5 VLAN function
VLAN function is a function that divides physical LAN into virtual multiple LANs, and executes grouping in port,
MAC address, protocol etc.
VLAN in device
VLAN prescribes communication method that has used VLAN group identification method which is called as
tagging method.
Tagging method is a method that identifies the VLAN to which this frame belongs by attaching VLAN tag to the
frame. The defined identifier is called as VLAN ID. When 1 VLAN is defined, corresponding 1 VLAN ID is also
assigned. VLAN function supported by this device is based on IEEE802.1q.
In this device, All the ports are initially set to VID=1 as ‘no tag’ of VLAN1, setting of each port can be changed to
‘with tag’or ‘no tag’ of specific VLAN.
VLAN and network address
When VLAN function is used, bridging communication is closed in this VLAN. Therefore, to define VLAN means
to restrict the broadcasting frame (Broadcasting domain) at the level of MAC address Furthermore, following 2
things can be done thought from the position of network layer.
• Multiple network addresses are made to correspond to each physical port by using the VLAN tag.
• 1 network address is assigned where multiple physical ports are bound.
Virtual Interface
VLAN1、VLAN2、VLAN3
Switching HUB(supported VLAN)
VLAN1
VLAN2
VLAN3

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VLAN type
In VLAN function supported by this device, VLAN can be divided in following 2 units.
•Port VLAN
It is the function that executes grouping in port unit. Addresses for all the network protocols can be given.
•Protocol VLAN
It is a function that groups the ports on the basis of specific protocols.
Types of protocols that can be specified by protocol VLAN are as follows.
- IP
- IPv6
Furthermore, protocol VLAN of optional protocol can be created by directly specifying the frame type. Exanoke)
IPX (Ethernet II type EtherType:Value [0x8137,0x8138] specification)
Relationship between VLAN tag and port
When VLAN function is used, it is defined whether VLAN tag is attached at the time of sending the frame to
port in VLAN in advance. Whether to attach or not is determined according to whether the node which is at the
end of each port can identify the VLAN tag.
When VLAN function is used, segment which is connected to the end of each port of this device belongs to any
one of the following 3.
•Access link
It is the section where only the frames with no VLAN tag flow. End node which cannot recognize VLAN tag is
connected.
•Trunk link
It is the section where only the frames with VLAN tag flow. Same devices which support VLAN function with tag,
are connected by normal trunk link. End node which cannot recognize VLAN tag is not connected.
•Hybrid link
It is the section where frames with and without VLAN tag flow. Here, multiple VLANs exist and there are access
links or trunk links for respecitve VLANs. However, if focus is on specific protocol, there is only 1 VLAN where
hybrid link can be operated as access link. For example, when 2 VLANs are operated as access links on 1 hybrid
link, and if focused on IP protocol, only 1 from this can be recognized.
Points to be noted
• When 2 or more VLANs are operated as access links for specific protocol, since VLAN tag is not attached to
frame which is sent by respective VLAN, to which VLAN the frame belongs cannot be identified.
• When it is used together with spanning tree function, bridge frame and routing frame are according to
restrictions on spanning tree.
• When protocol VLAN definition is set such that it exceeds the upper limit that can be set in device, VLAN ID
specified in protocol VLAN definition that exceeds the upper limit and protocol VLAN definition, becomes
invalid, and hence all the ports that belong to invalid VLAN ID cannot be used. In addition to this, upper limit
that can be set for protocol VLAN definition in the device is 16.

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Mixed VLAN on the same port
Combination of VLAN used by the same port is shown below.
: Can be mixed,×: Cannot be mixed
VLAN judgment at the time of receiving packets
When packets are received by the port set by VLAN, execute the judgment for received packets belonging to
VLAN by the following sequence.
) In this device, Tag VLAN/Protocol VLAN are defined by configuration definition and default VLAN is
created in the device for receiving BPDU packets for the port where port VLAN (untagged) is default.
VLAN tag at the time of sending packets
Handling of VLAN tag at the time of sending packets is according to Tagged / Untagged settings of
transmission port. In case of Tagged port, packets are sent with VLAN tag and in case of untagged port these
are sent without VLAN tag.
VLAN type
Port VLAN（untagged）
Protocol VLAN（untagged）
Tag VLAN（Tagged）
Port VLAN（untagged）
×
○
○
Protocol VLAN（untagged）
○
○
○
Tag VLAN（Tagged）
○
○
○
Packet receive
Is it tagged packets?
Does it match the VID,
which is defined port?
Tag VLAN
Discard
Protocol ＶＬＡＮ
Port ＶＬＡＮ
Default ＶＬＡＮ（※）
Discard
Is it matches the protocol
VLAN definition?
Is there a port VLAN
definition?
Is it BPDU packets?
Yes
Yes
Yes
Yes
Yes
No
No

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VLAN trunk function
The VLAN trunk function is a function to be used for communication between VLAN for a possibility of
switching when the VLAN tag is assigned and deleted. In order to carry out routing from the port which
belongs to multiple VLANs, it is relayed to other layer 3 switches. In the port, VLAN is tagged so that it can be
recognized that to which VLAN it belongs, and the frame with VLAN tag is received, routed and relayed with
layer 3 switches.
VLAN between devices
When VLAN crosses between the devices, by setting the VLAN tag to the frame, the VLAN wherefrom the
frame has come, is distinguished. As a result, similar VLAN A and VLAN B can communicate in such a way that
these are connected with same switching HUB. Usually, 2 transmission lines are required, by using the VLAN
trunk function, however, it can be connected by 1 transmission line in this device.

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2.6 Link aggregation function
Link aggregation function is a function for multiplexing the multiple ports and handling as 1 high speed link
(Trunk.Group). Hereon by using this function, it is possible to improve the redundancy of the link by
distributing that traffic to the other port when 1 multiplexed link (Member port) is failed.
Link aggregation function is also called as multi link ethernet or port trunking.
Furhter, configure the member ports in 1~10 ports.
Set the all member ports similar to the VLAN configuration.
The traffic to Trunk group is judged by the IP address and MAC address of transmission packet for distributing
the load.
Can be specified by selecting from the following methods.
Distribution of the load based on sending destination MAC address and sending source MAC address.
Distribution of the load based on sending destination MAC address.
Distribution of the load based on sending source MAC address.
Distribution of the load based on sending destination IP address and sending source IP address.
Load balancing based on sending destination IP address
Load balancing based on sending source IP address
Load balancing based on the reception Ethernet port
It is possible to specify the minimum member port count, the trunk group can communicate.
Trunk group communication is terminated until the count which specifies the member port of the trunk. Group
is enabled.
For example, member port where linkdown is executed is not included in the enable port etc.
In redundant configuration the trunk group is used when communication cannot be carried out until a
necessary bandwidth is secured
Further it is possible to use this function with LACP.
Points to be noted
• Port which is multiplexed is handled as 1 port. It is similar when STP or VLAN functions are used together.
• Calculate the cost of STP according to bandwidth of member port and member count, and allocate the cost
value
It is not possible to change the cost according to degeneracy/recovery.
40Gbps virtual link
10Gbps

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2.6.1 LACP Function
The LACP function is link aggregation which uses IEEE802.3 compliant LACP. Link aggregation of feasible
maximum level is continuously provided between the systems having LACP.
Confirmation of consistency of link aggregation or confirmation of link consistency and accuracy of fault
detection is improved by using LACP.
Merits of introduction
▪As it confirms consistency with the adjacent equipment, for example if there are mistakes such as wrong
judgment of the port, the communication begins by confirming one by one destination connected to the correct
link by using the protocol levels. Therefore, communication with the wrong connection is not possible.
▪When the LACP packet from the adjacent device is not received during the fixed time, since there is
determination of fault link, fault detection of link which exceeds the fault detection range of device port is
possible.
Points to be noted
▪It is necessary to enable the LACP before connection for the link aggregation which uses LACP. Link
aggregation other than LACP where ‘static’ is specified in link aggregation mode cannot be connected.
▪By specifying ‘passive’ in link aggregation operation mode, link aggregation which is similarly set to ‘passive’
before connection, cannot be configured. Specify ‘active’ for either of the two.Both can be specified as ‘active’.
Refer to “2.6 link aggregation function” for other notes.
10Gbps
40Gbps virtual link

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2.7 Back-up port function
Back-up port function groups the two ports and manages port on one side as master port (Priority port) and
port on the other side as back-up port (Standby port). Further it decides port on which side should be activated.
If any error has occurred while running, port on the other side immediately switches over to activate port and it
is possible to control the network error is not much affected. In a state where group ports are linked up together,
mode which uses the master port on priority basis without fail and mode which linkedup port in the beginning
can be selected. Moreover, linkaggregation can be used as a backup port.
Points to be noted
▪In the back-up port function, if error occurs, it is possible to switch over the active port at once and when
various protocols are used, restoration time of each protocol till restoring the communication is required.
▪When it is used together with link aggregation, if that link aggregation has mismatched settings for back-up
configuration, link aggregation becomes disabled.
▪If standby status of standby port is set to offline, the standby port is linked down, therefore even if
abnormality such as line omission etc has occurred it cannot be detected. After switching over the operation, it
changes to abnormality is detected.

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2.8 STP Function
STP Function connects the different LANs and broadcasts MAC frames.
In this device, the following functions are supported.
2.8.1 STP
This is IEEE 802.1D Spanning Tree Protocol (STP). The spanning tree is a function which prevents the loop when
multiple paths are connected. To achieve that, STP has only one path be a communication path and configures
the tree structure network logically.
By using this function, the loop of the frames connected with the system down is not generated. Moreover, a
strong network can be constructed for failure.
STP chooses the root bridge that is the root of the logical tree structure network. Then, it decide a STP port
mode for each ports. The mode is root port, designated port or blocking port. The root port and designated port
forward the packets though blocking port does not forward.
STP interface have the following states to achieve above function
-Blocking: This does not forward frames.
-Listening: Transitional state. This is the next state of the blocking when the port become forwarding state.
-Learning: Transitional state. This is the next state of the listening.
-Forwarding: This forwards frames.

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Procedures to decide root port/ representative port/ blocking port
Procedure to decide various ports is as follows.
※1）Following is the default cost value at the time of selecting ‘AUTO’.
Transmission speed
Default path cost
10G
2000
40G
1200
At the time of link aggregation, transmission speed becomes 200 in case of 10G and 120 in case of 40G.
※2）• The route path cost is a total of the path cost of the port which inputs configuration BPDU packet in the
route from the root bridge and the least value is accepted.
• Path cost of the root bridge is 0.
※3）• One root port exists in each bridge.
• When the route path cost is same, the port identifier adopts the small port.
※4）• One representative port exists in each segment.
• When there are more than 2 ports which have least values, port with least bridge priority is adopts.
It is determined in each path port(It can be set in each port, and select the AUTO
usually)（※1）
You assigned to each bridge the bridge priority.
It selects the port with the lowest value by calculating for each port of the bridge
the root path cost(minimum path cost to the root bridge).
（※
2
）
Port with the root path cost of the minimum in each bridge within is not the root
bridge becomes the root port.
（※
3
）
Port with the root path cost of the minimum in bridge that connects to each
segment becomes the designated port.
（※
4
）
Port that is not a designated port and a root port become the blocking port.
START
END
Decision of
root bridge
Decision of
root port
The bridge with the bridge priority of the minimum becomes the root bridge.
Decision of
designated port
Decision of
blocking port

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Network settings using spanning tree function
Parameters in spanning tree
In spanning tree, several parameters are set in bridge in order to implement the designed tree structure and
tree performance. The tree structure and tree performance is determined according to this parameter.
<Parameter that determines the tree structure> The tree structure is determined as per the following
parameters.
Parameters
Setting
target
Remarks
Bridge Priority
(STP bridge priority)
Every
Bridge
It is set for every bridge, and bridge that sets the minimum value is used as
priority route. Minimum value in the system is set for the bridge which is
considered as root bridge.
Port Identifier
(STP port identifier)
Every port
When the judgment of root path cost and bridge identifier is not used, the
prominent port of port identifier is considered as designated port. Since the
MAC address is included in bridge identifier, the designated port is not
determined in port identifier.
Path cost
(STP port path cost)
Every port
Root port (Route of upper bridge) is determined. The designated port
(Designated bridge) is determined as per path cost and bridge priority. The root
of minimum value set on each port in the bridge is selected. The slow root of
transmission speed sets the high cost and uses for the backup.
It is suggested that the default value (1000÷ transmission speed Mbps) is used
for the path cost.
<Parameters of determining the tree performance>
The tree performance (Root change time during failure etc) is determined as per the following parameters
Parameters
Setting
target
Remarks
Hello Time
(STP bridge hello time)
Every
Bridge
Since the root bridge confirms the tree structure, it is considered as the sending
interval of configuration BPDU. Recommended time is 2 seconds.
Maximum age
(STP bridge Max age)
Every
Bridge
It is a timer value that starts the restructure of tree since configuration BPDU is
not delivered. It differs as per the delay time till configuration BPDU is delivered
to the bridge of tree structure terminal but the recommended time is 20
seconds. In order to restructure in the same timing, the bridge in same network
is set with the same parameter.
Forward delay
(STP bridge forward
delay)
Every
Bridge
It is waiting period in intermediate status till the blocking status is changed to
forwarding status.
If this time is short, synchronization of the entire tree structure in the listening
status is not acquired. In the learning status, since the learning of MAC address
learning status is inadequate, there are possibilities such as all the ports are
broadcasted or changes to loop status. Further, if the time is long, the time
required for the restructuring of tree gets longer. Recommended time is 15
seconds.
<Other parameters>
Parameters
Setting
target
Remarks
STP domain separation
(STP domain Separation)
Every port
Set whether the STP domain is separated in each port of bridge.
If STP domain is separated, the transmission of configuration BPDU from that
port is stopped.
Port which sets by separating the STP domain does not configure the STP tree.
However, the frame other than configuration BPDU is broadcasted.
ON：STP domain is not separated,
OFF：Set by separating the STP domain.

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2.8.2 RSTP
As a problem of STP, the communication may get disconnected for maximum 50 seconds. The protocol
developed to overcome the problem is RSTP (rapid spanning tree protocol). When RSTP is used, spanning tree is
calculated again for 1 second, and the change over at instantaneous interruption level becomes possible.
Moreover, RSTP is standardized as IEEE802.1w and is compatible with conventional STP（IEEE802.1d）.Therefore,
the mixed environment with STP operates without trouble.
Role of port in RSTP
The role of each port is as follows in STP.
•Designated port
• Root port
• Blocking port
In RSTP, specified port and root port are used as same role in STP. The blocking port is used by dividing it into
the following 2 roles.
• Alternate port
Port where alternate path is provided. There is a port, which has less cost, next to root port and it becomes the
port having alternate path to root bridge.
• Back up port
It is a port of the alternate path of the route specified by specified port. When there are more than 2
connections for the same segment on 1 switch, it is provided as alternate path.
Alternate port and backup port will changes to the normal blocking status.
State of port in RSTP
In STP, there are four states of the port such as the blocking state, the listening state, the learning state, and
the forwarding state. The broadcast of MAC frame is neither executed in the blocking state nor in the listening
state. The only point of difference between the both is, BPDU transmission is not executed in the blocking state
and BPDU transmission is executed in the listening state.
In the RSTP, the blocking state and the listening state together becomes the discarding state.

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2.8.3 MSTP
Depend on VLAN configuration, there may not be any loops even if it looks no-loop in physical network. In that
case, STP decides it as loop network, but MSTP does not because it can handle the network per VLAN. Therefore,
MSTP can forward network data more efficiently than STP.
For example, There are 4 switches called Bridge A, Bridge B, Bridge C, and Bridge D and connect them as below
diagram. topology. Using MSTP, we can forwards vlan 100, 200 frame from Bridge D –Bridge B –Bridge A and
forwards vlan 300 frame from Bridge D –Bridge C –Bridge A. We can not use STP for such behavior.