¾ Dhcp Cheating Attack | TP-Link TL-SL5428E manual

Option 82 can contain 255 sub-options at most. If Option 82 is defined, at least a sub-option should be defined. This Switch supports two sub-options: Circuit ID and Remote ID. Since there is no universal standard about the content of Option 82, different manufacturers define the sub-options of Option 82 to their need. For this Switch, the sub-options are defined as the following: The Circuit ID is defined to be the number of the port which receives the DHCP Request packets and its VLAN number. The Remote ID is defined to be the MAC address of DHCP Snooping device which receives the DHCP Request packets from DHCP Clients.

¾DHCP Cheating Attack

During the working process of DHCP, generally there is no authentication mechanism between Server and Client. If there are several DHCP servers in the network, network confusion and security problem will happen. The common cases incurring the illegal DHCP servers are the following two:

（1） It’s common that the illegal DHCP server is manually configured by the user by mistake.

（2） Hacker exhausted the IP addresses of the normal DHCP server and then pretended to be a legal DHCP server to assign the IP addresses and the other parameters to Clients. For example, hacker used the pretended DHCP server to assign a modified DNS server address to users so as to induce the users to the evil financial website or electronic trading website and cheat the users of their accounts and passwords. The following figure illustrates the DHCP Cheating Attack implementation procedure.

Figure 11-7 DHCP Cheating Attack Implementation Procedure

DHCP Snooping feature only allows the port connected to the DHCP Server as the trusted port to forward DHCP packets and thereby ensures that users get proper IP addresses. DHCP Snooping is to monitor the process of the Host obtaining the IP address from DHCP server, and record the IP address, MAC address, VLAN and the connected Port number of the Host for automatic binding. The bound entry can cooperate with the ARP Inspection, IP Source Guard and the other security protection features. DHCP Snooping feature prevents the network from the DHCP Server

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TP-Link TL-SL5428E manual ¾ Dhcp Cheating Attack, Dhcp Cheating Attack Implementation Procedure

Contents

Rev 1910010529 Copyright & Trademarks Contents Gvrp TC Protect 101 11.4.1 11.4.2 Ntdp VII Package Contents Conventions About this GuideIntended Readers Overview of This Guide Path Switch, which facilitates you to monitor the Igmp messages Return to Contents Introduction Overview of the SwitchMain Features ¾ LEDs Name Status Indication Appearance DescriptionFront Panel Rear Panel Configuration Login to the SwitchLogin Return to Contents System Summary SystemSystem Info ¾ Port Status Type ¾ Port InfoPort Rate ¾ Device Description Device Description¾ Bandwidth Utilization ¾ Time Info ¾ Time ConfigSystem Time System IP User Manage User Table User Config ¾ User Info Confirm Password Retype the password Config RestorePassword User ID, Name, Access Level and status Operation ¾ Config Backup Config BackupFirmware Upgrade System Reboot System Reset Access Security Access Control IP Address&Mask ¾ Access Control Config¾ Session Config MAC Address SSL Config ¾ Access User Number ¾ Certificate Download SSH Config¾ Global Config ¾ Key Download Max Connect Idle TimeoutProtocol Download ¾ Configuration ProcedureKey Type ¾ Network Requirements Application Example 2 for SSH Page Return to Contents Port SwitchingPort Config Port Select Speed and Duplex Port MirrorDescription Flow Control Ingress ¾ Mirroring Port¾ Mirrored Port Egress Port Security ¾ Port Security Learned Num Port IsolationMax Learned MAC ¾ Port Isolation List ¾ Port Isolation ConfigForward Portlist Select the port that to be forwarded to Forward Portlist Display the forwardlist LAG LAG Table Group Number Aggregate Arithmetic¾ LAG Table Member ¾ LAG Config Static LAG Lacp Config LAG will delete this LAG System Priority ¾ Lacp ConfigAdmin Key Port Priority ¾ Auto Refresh Traffic MonitorTraffic Summary Traffic Statistics MAC Address Bound Type Configuration Way Aging outRelationship Address and the port ¾ Search Option ¾ Address Table Displays the corresponding Vlan ID of the MAC address MAC Address Displays the MAC address learned by the switchStatic Address ¾ Create Static Address Dynamic Address ¾ Static Address Table ¾ Aging Config ¾ Dynamic Address Table Filtering Address Bind ¾ Create Filtering Address ¾ Filtering Address Table Vlan Vlan implementation 802.1Q Vlan ¾ Link Types of ports Vlan Config ¾ Pvid Description ： ¾ Vlan TableVlan ID Select Members Operation ： Is valid or not ¾ Vlan ConfigEnter the ID number of Vlan ¾ Vlan Members ¾ Vlan Port Config Port Displays the port number ¾ Vlan of Port Required. On the VLAN→802.1Q VLAN→Port Config page, setRequired. On the VLAN→802.1Q VLAN→VLAN Config Vlan Description Optional. On the VLAN→802.1Q VLAN→VLAN Config MAC Vlan MAC Select Port Enable¾ MAC Vlan Table Required. On the VLAN→MAC VLAN→Port Enable Protocol Vlan ¾ Create Protocol Vlan Protocol VlanProtocol Template ¾ Protocol Vlan Table ¾ Create Protocol Template ¾ Protocol Template Table Application Example for 802.1Q Vlan Application Example for MAC Vlan Required. On VLAN→802.1Q VLAN→Port Config page, configureRequired. On VLAN→802.1Q VLAN→VLAN Config page, create a Operation Description ¾ Network Diagram ¾ Configuration Procedure Application Example for Protocol Vlan Required. On VLAN→Protocol VLAN→Protocol Template On VLAN→Protocol VLAN→Protocol Vlan page, create protocol Protocol type Value ¾ VPN Up-link Ports VPN ConfigVlan Mapping ¾ Vlan Mapping Config ¾ Vlan Mapping Table Required. On the VLAN→VLAN VPN→Port Enable Required. On the VLAN→VLAN VPN→VPN ConfigOptional. On the VLAN→VLAN VPN→VPN Config Required. On the VLAN→VLAN VPN→VLAN Mapping Gvrp ¾ Garp ¾ Gvrp ¾ Port Config Select Port Status Registration Mode Configuration Procedure Private Vlan ¾ Private Vlan Implementation ¾ Features of Private Vlan¾ The Elements of a Private Vlan Pvid ¾ Packet forwarding in Private Vlan Pvlan Primary Vlan ¾ Create Private Vlan¾ Private Vlan Table Secondary Vlan ¾ Private Vlan Port Table Port Select the desired port for configuration Port TypeRequired. On the VLAN→Private VLAN→Port Configure Required. On the VLAN→Private VLAN→PVLAN Application Example for Private Vlan Required. On the VLAN→802.1Q VLAN→VLAN Config page, click Spanning Tree ¾ STP Elements ¾ STP Timers ¾ Bpdu Comparing Principle in STP mode ¾ STP Generation Step Operation ¾ Mstp Elements Tips：¾ Rstp Elements ¾ Port States ¾ Port Roles STP Config STP Config Hello Time Forward DelayVersion Max Age STP Summary Port Config STP Summary IntPath PriorityExtPath Edge Port Port Role Region ConfigMstp Instance Port Status Instance Config ¾ Region Config Instance Instance Port Config¾ Instance Table Clear Instance ID Path Cost STP Security Port Protect ¾ Bpdu Filter ¾ TC Protect¾ Bpdu Protect TC Protect Loop ProtectRoot Protect Bpdu Protect TC Protect 11 TC Protect Application Example for STP Function On Spanning Tree→STP Config→STP ConfigOn Spanning Tree→STP Config→Port Config On Spanning Tree→MSTP Instance→Instance Bridge of Instance Configure Switch D ¾ Suggestion for Configuration ¾ Multicast Address Multicast¾ Multicast Overview ¾ Multicast Address Table Multicast IP Port ¾ Igmp Snooping Process Igmp Snooping¾ Igmp Snooping ¾ Igmp Messages Snooping Config ¾ Igmp Snooping Fundamentals ¾ Igmp Snooping Status Description Displays Igmp Snooping status Member Igmp Snooping Fast Leave Leave Time Router Port TimeMember Port Time Static Router Port Multicast Vlan Snooping→Snooping Config and Port ConfigMulticast→IGMP Snooping→VLAN Config Router Port ¾ Multicast Vlan Vlan On the Multicast→IGMP Snooping→Snooping ConfigApplication Example for Multicast Vlan Multicast→IGMP Snooping→Multicast Vlan Snooping→Snooping Config ¾ Configuration Procedure Step Operation DescriptionSnooping→Port Config Multicast IP Multicast IP Table Static Multicast IP ¾ Create Static Multicast ¾ Static Multicast IP Table Multicast Filter IP-Range ¾ Port Filter Config Port Filter Multicast→Multicast Filter→Port Filter Packet StatisticsMulticast→Multicast Filter→IP-Range ¾ Igmp Statistics ¾ QoS ¾ Priority ModeQoS ¾ Schedule Mode 802.1Q frame SP-Mode Port Priority ¾ Port Priority ConfigDiffServ Displays the LAG number which the port belongs to Schedule Mode ¾ Schedule Mode Config ¾ Priority Level ¾ 802.1P Priority Config3 802.1P Priority Dscp Priority Priority Level ¾ Dscp Priority ConfigIt ranges from 0 to Priority levels are labeled as TC0, TC1, TC2 and TC3 Rate Limit ¾ Rate Limit ConfigBandwidth Control Egress Ratebps Storm ControlIngress Rate bps Bps ¾ Storm Control ConfigBroadcast Rate Multicast Rate Number OUI Address Vendor ¾ Port Voice Vlan ModeVoice Vlan ¾ Security Mode of Voice Vlan Packet Type Processing Mode Global Config 12 Global Configuration Port Mode 13 Port Config OUI Config Required. On QoS→Voice VLAN→Port Config Required. On VLAN→802.1Q VLAN→Port ConfigOptional. On QoS→Voice VLAN→OUI Config page, you Required. On QoS→Voice VLAN→Global Config Time-Range Summary ACLTime-Range Index Time-Range Create ¾ Create Holiday ACL ConfigHoliday Config ¾ Holiday Table ¾ Rule Table ACL SummaryACL Create ¾ Create ACL Rule ID MAC ACL¾ Create MAC ACL EtherType Fragment Standard-IP ACL¾ Create Standard-IP ACL Mask Extend-IP ACL ¾ Create Extend-IP ACL Policy Config Policy Summary Select Policy Policy CreateAction Create Desired policy, please click the Delete button 11 Action Create ¾ Create Action Port Binding Policy BindingBinding Table ¾ Policy Bind Table Enter the ID of the Vlan you want to bind Vlan BindingDirection Displays the binding direction Application Example for ACL ¾ VLAN-Bind Table On ACL→ACL Config→ACL Create page, create ACL On ACL→ACL Config→Standard-IP ACL page, select ACL Network Security IP-MAC Binding Manual Binding Protect Type Select the Protect Type for the entry ¾ Manual Binding OptionEnter the Vlan ID ¾ Manual Binding Table ARP Scanning End IP Address Dhcp SnoopingStart IP Address Scan Network diagram for DHCP-snooping implementation ¾ Dhcp Working Principle ¾ Option Dhcp Cheating Attack Implementation Procedure ¾ Dhcp Cheating Attack 163 Decline Threshold Decline Flow Control ¾ Option 82 Config¾ Port Config Port Select Customization Circuit ID Remote ID ¾ Cheating Gateway ARP Inspection¾ Imitating Gateway 10 ARP Attack Cheating Gateway ¾ Cheating Terminal Hosts ¾ Man-In-The-Middle Attack ¾ ARP Flooding Attack ¾ Trusted Port ARP Detect¾ ARP Detect Network Security→ARP ARP DefendRequired. On the Network Security→IP-MAC Defend ARP Statistics¾ ARP Defend Speed IP Source Guard ¾ Illegal ARP Packet ¾ IP Source Guard Config DoS Defend DoS Attack Type Description DoS Defend DoS Detect Detect 11.5Detect Time Attack Type ¾ The Mechanism of an 802.1X Authentication System ¾ 802.1X Authentication Procedure 178 179 ¾ 802.1X Timer ¾ Guest Vlan Guest Vlan Authentication Method802.1X Guest Vlan ID Retry Times Supplicant TimeoutServer Timeout Control Type Control ModeRadius Server Authorized Required. On the Network Security→802.1X→Radius On the Network Security→802.1X→Global Config802.1X Client Software Required. On the Network Security→802.1X→Port ¾ Snmp Management Frame Snmp¾ Snmp Overview ¾ Snmp Versions ¾ Snmp Configuration Outline ¾ MIB Introduction ¾ Remote Engine Snmp Config¾ Local Engine View Type Snmp ViewMIB Object ID View Name ¾ Group Config Snmp Group Snmp User ¾ Group Table Privacy Mode Auth ModeAuth Password Privacy Password Snmp Community ¾ Community ConfigAccess MIB View Required. On the SNMP→SNMP Config→GlobalRequired. On the SNMP→SNMP Config→SNMP ¾ Community Table On the SNMP→SNMP Config→SNMP Notification User TimeoutUDP Port Retry Rmon Group Function Rmon¾ Rmon Group ¾ History Control Table Event ConfigHistory Control Alarm Config ¾ Event Table Rising Threshold VariableSample Type Rising Event 200 Cluster ¾ Cluster Role ¾ Introduction to Cluster 13.1 NDPNeighbor Info ¾ Neighbor Info NDP Summary¾ Neighbor ¾ Port Status Displays the port number of the switch NDP Aging Time NDP ConfigDetail ： Device Table Port Displays the port number of the switchNtdp Displays NDP status of the current port Ntdp Summary Ntdp Summary Ntdp Hops Ntdp ConfigNtdp Interval Time Cluster Summary EnableCluster ¾ Global Cluster ¾ Global Config Cluster¾ Cluster Config ¾ Member Info Switch 11 Cluster Summary for Member Switch ¾ Role Change Cluster Config¾ Current Role 14 Cluster Configuration for Commander Switch Member Config 16 Cluster Configuration for Individual Switch Device Name Cluster Topology¾ Create Member Member MAC 18 Collect Topology ¾ Graphic Show Application Example for Cluster Function On Cluster→NDP→NDP Config page, enable NDP On Cluster→NTDP→NTDP Config page, enable 220 CPU Monitor MaintenanceSystem Monitor Memory Monitor 14.2 Log Time ContentLog Table Module Remote Log ¾ Local Log ConfigLocal Log Log Buffer Host IP Backup Log¾ Log Host Cable Test ¾ Backup LogDevice Diagnose ¾ Cable Test Loopback ErrorSwitch is available Length Ping ¾ Ping ConfigNetwork Diagnose Test ¾ Tracert Config Tracert Configure the Hyper Terminal System Maintenance via FTPHardware Installation 232 Download Firmware via bootrom menu 5Port Settings TP-LINK ifconfig ip 172.31.70.22 mask 255.255.255.0 gateway TP-LINK upgrade You can only use the port 1 to upgrade TP-LINK start Start User Access Login Appendix a Specifications Appendix B Configuring the PCs Configure TCP/IP component 238 Now Installation Guide Appendix C 802.1X Client Software 241 242 Uninstall Software Figure C-7 InstallShield Wizard Complete Configuration Figure C-10 Uninstall Complete 245 Figure C-15 Connection Status FAQ Appendix D Glossary Ieee 802.1D Multicast SwitchingGroup Attribute Registration Protocol Garp Ieee 802.1Q Link Aggregation Port AuthenticationRemote Authentication Dial-in User Service Radius Link Aggregation Control Protocol Lacp Spanning Tree Algorithm STA Simple Network Management Protocol SnmpSimple Network Time Protocol Sntp Telnet