¾ STP Timers, ¾ STP Generation | TP-Link TL-SG2008 manual

Figure 7-1 Basic STP diagram

¾STP Timers

Hello Time:

Hello Time ranges from 1 to 10 seconds. It specifies the interval to send BPDU packets. It is used to test the links.

Max. Age:

Max. Age ranges from 6 to 40 seconds. It specifies the maximum time the switch can wait without receiving a BPDU before attempting to reconfigure.

Forward Delay:

Forward Delay ranges from 4 to 30 seconds. It specifies the time for the port to transit its state after the network topology is changed.

When the STP regeneration caused by network malfunction occurs, the STP structure will get some corresponding change. However, as the new configuration BPDUs cannot be spread in the whole network at once, the temporal loop will occur if the port transits its state immediately. Therefore, STP adopts a state transit mechanism, that is, the new root port and the designated port begins to forward data after twice forward delay, which ensures the new configuration BPDUs are spread in the whole network.

¾BPDU Comparing Principle in STP mode

Assuming two BPDUs: BPDU X and BPDU Y

If the root bridge ID of X is smaller than that of Y, X is superior to Y.

If the root bridge ID of X equals that of Y, but the root path cost of X is smaller than that of Y, X is superior to Y.

If the root bridge ID and the root path cost of X equal those of Y, but the bridge ID of X is smaller than that of Y, X is superior to Y.

If the root bridge ID, the root path cost and bridge ID of X equal those of Y, but the port ID of X is smaller than that of Y, X is superior to Y.

¾STP Generation

zIn the beginning

In the beginning, each switch regards itself as the root, and generates a configuration BPDU for each port on it as a root, with the root path cost being 0, the ID of the designated bridge being that of the switch, and the designated port being itself.

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TP-Link TL-SG2008 manual ¾ STP Timers, ¾ Bpdu Comparing Principle in STP mode, ¾ STP Generation

Contents

REV1.0.0 1910010984 TL-SG2008 Copyright & Trademarks FCC Statement Safety Information Contents Loopback Detection 100 Rmon Package Contents Intended Readers About this GuideConventions Overview of This Guide System Chapter Introduction Appendix a Specifications Main Features Overview of the SwitchIntroduction Appearance Description ¾ LEDs Name Status Indication Rear Panel Configuration Login to the SwitchLogin Return to Contents System Info SystemSystem Summary ¾ Port Status ¾ Port Info Device DescriptionStatus Displays the connection status of the port ¾ Bandwidth Utilization ¾ Time Info System Time¾ Device Description Daylight Saving Time System IP Following entries are displayed on this screen System IP User Table ¾ IP ConfigUser Management Password Type in a password for users’ login User Config¾ User Info User Status Confirm Password Password Display Mode Config RestoreUser ID, Name, Access Level and status Operation System Tools ¾ Config Backup Config BackupFirmware Upgrade System Reset System Reboot Access Control Access Security IP Address & Mask SSL ConfigMAC Address Port ¾ Certificate Download ¾ Global Config¾ Key Download Key File Select Enable/Disable SSH function SSH Config ¾ Network Requirements ¾ Configuration ProcedureDownload Application Example 2 for SSH Page Page Return to Contents Port SwitchingPort Config Group Port MirrorMirroring Mode Egress NumberIngress ¾ Port Security Port Security Port Isolation Port Isolation Loopback Detection ¾ Port Isolation Config¾ Port Isolation List Forward Portlist Display the forwardlist LAG Operation Mode ¾ LAG Table LAG Table Member Static LAGGroup Number LAG will delete this LAG Lacp Config Port Priority ¾ Lacp ConfigAdmin Key Traffic Summary Traffic MonitorPackets Rx Packets Tx Refresh Rate Traffic Statistics¾ Statistics Received Bound MAC address MAC AddressWay Port ¾ Search Option Address Table Static Address MAC Address Displays the MAC address learned by the switch¾ Address Table Displays the corresponding Vlan ID of the MAC address ¾ Static Address Table Dynamic Address Bind ¾ Aging Config¾ Dynamic Address Table ¾ Create Filtering Address Filtering Address ¾ Dhcp Working Principle Dhcp Filtering¾ Filtering Address Table 17 Network diagram of Dhcp ¾ Dhcp Cheating Attack 19 Dhcp Cheating Attack Implementation Procedure ¾ Trusted Port ¾ Dhcp FilteringDhcp Filtering Vlan ¾ Link Types of ports 802.1Q Vlan ¾ Pvid Vlan Config Name Give a name to the Vlan for identificationUntagged Ports Tagged Ports Application Example for 802.1Q Vlan ¾ Network DiagramUntagged Tagged Step Operation Description Required. On VLAN→802.1Q VLAN→VLAN Config page, configureRequired. On VLAN→802.1Q VLAN→VLAN Config page, create a ¾ STP Elements Spanning Tree ¾ STP Generation ¾ STP Timers¾ Bpdu Comparing Principle in STP mode Tips ： Step Operation ¾ Mstp Elements ¾ Rstp Elements ¾ Port Roles ¾ Port States STP Config STP Config Version Forward DelayHello Time Max Age STP Summary Port Config ExtPath PriorityIntPath Edge Port Instance Config Region Config¾ Region Config Mstp Instance Instance ¾ Instance TableClear ¾ VLAN-Instance Mapping Path Cost Instance Port ConfigInstance ID Port Protect STP Security ¾ TC Protect ¾ Root Protect¾ Bpdu Protect ¾ Bpdu Filter TC Protect 11 TC Protect Application Example for STP Function On Spanning Tree→MSTP Instance→Region On Spanning Tree→STP Config→STP ConfigOn Spanning Tree→MSTP Instance→Instance Operation Description On Spanning Tree→STP Config→Port Config ¾ Suggestion for Configuration ¾ Multicast Overview Multicast ¾ Multicast Address Table ¾ Multicast Address Multicast IP Port Igmp Snooping¾ Igmp Snooping ¾ Igmp Snooping Process ¾ Igmp Snooping Fundamentals Snooping Config Description Displays Igmp Snooping status Member ¾ Igmp Snooping Status Fast Leave Igmp Snooping Multicast Vlan ¾ Multicast Vlan Multicast→IGMP Snooping→Multicast Vlan On the Multicast→IGMP Snooping→Snooping ConfigVlan Snooping→Snooping Config Snooping→Port ConfigMulticast IP Multicast IP Table Static Multicast IP ¾ Static Multicast IP Table Multicast Filter¾ Create Static Multicast Port Filter IP-Range Action Mode ¾ Port Filter ConfigFilter Bound IP-Range ID Packet Statistics Port Displays the port number of the switch Query PacketMulticast→Multicast Filter→IP-Range Multicast→Multicast Filter→Port Filter Return to Contents ¾ QoS ¾ Priority ModeQoS 802.1Q frame ¾ Schedule Mode SP-Mode DiffServ ¾ Port Priority ConfigPort Priority Displays the LAG number which the port belongs to 2 802.1P/CoS Mapping ¾ 802.1P Priority ConfigRequired. On QoS→DiffServ→Port Priority ¾ Priority Level ¾ Dscp Priority Config Configuration Procedure Step Operation DescriptionDscp Priority Mapping ¾ Priority Level Schedule ModeIt ranges from 0 to Priority Level Rate Limit ¾ Rate Limit ConfigBandwidth Control Egress Ratebps Storm ControlIngress Rate bps Broadcast Rate Voice VlanBps Mulitcast Rate ¾ Port Voice Vlan Mode Packet Type Processing Mode Global Config¾ Security Mode of Voice Vlan Enter the Vlan ID of the voice Vlan Port ModeAging Time OUI address is aging out OUI Config Optional. On QoS→Voice VLAN→OUI Config page, you Required. On VLAN→802.1Q VLAN→VLAN ConfigRequired. On QoS→Voice VLAN→Port Config Required. On QoS→Voice VLAN→Global Config ACL ACL ConfigACL Summary ACL Create ¾ Create ACL MAC ACL¾ Create MAC ACL Rule ID Extend-IP ACL Standard-IP ACL¾ Create Standard-IP ACL Mask Policy Summary Policy Config¾ Create Extend-IP ACL IP Protocol Action Create Policy CreateIndex Displays the index of the policy Displays the ID of the ACL contained in the policy Binding Table Policy Binding¾ Create Action ¾ Policy Bind Table Vlan Binding Port BindingInterface Direction Displays the binding direction Application Example for ACL ¾ VLAN-Bind ConfigEnter the ID of the Vlan you want to bind ¾ VLAN-Bind Table On ACL→ACL Config→Standard-IP ACL page, select ACL On ACL→ACL Config→ACL Create page, create ACL Limit2 ¾ Snmp Overview Snmp¾ Snmp Management Frame ¾ Snmp Versions ¾ MIB Introduction ¾ Snmp Configuration Outline Snmp Config, Notification and Rmon Snmp Config Snmp Group Snmp ViewMIB Object ID View Type Snmp Group Following entries are displayed on this screen ¾ Group Config ¾ Group Table Snmp User Auth Password Auth ModePrivacy Mode Privacy Password Snmp Community AccessCommunity Name MIB View Required. On the SNMP→SNMP Config→SNMP Required. On the SNMP→SNMP Config→GlobalConfig→Global Config page, enable Snmp On the SNMP→SNMP Config→SNMP ¾ Create Notification NotificationIP Address UDP Port Rmon TimeoutRetry ¾ Notification Table ¾ History Control Table History ControlRmon Group Function ¾ Event Table Event ConfigAlarm Config Sample Type VariableRising Threshold Rising Event 131 CPU Monitor MaintenanceSystem Monitor Level Description 12.2 LogMemory Monitor Level Description Debugging Log Table¾ Log Info Time Local Log ¾ Local Log ConfigLog Buffer Log File Remote Log Backup Log¾ Log Host Host IP ¾ Backup Log Device DiagnosticsCable Test ¾ Cable Test Loopback Network Diagnostics Tracert ¾ Ping ConfigPing 10 Tracert Following entries are displayed on this screen ¾ Tracert Config Appendix a Specifications Configure TCP/IP component Appendix B Configuring the PCs Now Appendix C Glossary Remote Authentication Dial-in User Service Radius Multicast SwitchingIgmp Snooping Igmp Query Simple Network Management Protocol Snmp Rapid Spanning Tree Protocol RstpSimple Network Time Protocol Sntp Spanning Tree Algorithm STA