Web Management Guide-R04
Table Of Contents
- How to Use This Guide
- Contents
- Figures
- Tables
- Getting Started
- Web Configuration
- Using the Web Interface
- Basic Management Tasks
- Displaying System Information
- Displaying Hardware/Software Versions
- Configuring Support for Jumbo Frames
- Displaying Bridge Extension Capabilities
- Managing System Files
- Setting the System Clock
- Configuring the Console Port
- Configuring Telnet Settings
- Displaying CPU Utilization
- Configuring CPU Guard
- Displaying Memory Utilization
- Resetting the System
- Interface Configuration
- VLAN Configuration
- Address Table Settings
- Spanning Tree Algorithm
- Congestion Control
- Class of Service
- Layer 2 Queue Settings
- Layer 3/4 Priority Settings
- Setting Priority Processing to IP Precedence/DSCP or CoS
- Mapping Ingress DSCP Values to Internal DSCP Values
- Mapping CoS Priorities to Internal DSCP Values
- Mapping Internal DSCP Values to Egress CoS Values
- Mapping IP Precedence Values to Internal DSCP Values
- Mapping IP Port Priority to Internal DSCP Values
- Quality of Service
- VoIP Traffic Configuration
- Security Measures
- AAA Authentication, Authorization and Accounting
- Configuring User Accounts
- Web Authentication
- Network Access (MAC Address Authentication)
- Configuring HTTPS
- Configuring the Secure Shell
- Access Control Lists
- Filtering IP Addresses for Management Access
- Configuring Port Security
- Configuring 802.1X Port Authentication
- DoS Protection
- DHCPv4 Snooping
- DHCPv6 Snooping
- IPv4 Source Guard
- IPv6 Source Guard
- ARP Inspection
- Application Filter
- Basic Administration Protocols
- Configuring Event Logging
- Link Layer Discovery Protocol
- Simple Network Management Protocol
- Configuring Global Settings for SNMP
- Setting Community Access Strings
- Setting the Local Engine ID
- Specifying a Remote Engine ID
- Setting SNMPv3 Views
- Configuring SNMPv3 Groups
- Configuring Local SNMPv3 Users
- Configuring Remote SNMPv3 Users
- Specifying Trap Managers
- Creating SNMP Notification Logs
- Showing SNMP Statistics
- Remote Monitoring
- Switch Clustering
- Setting a Time Range
- Ethernet Ring Protection Switching
- OAM Configuration
- Connectivity Fault Management
- Configuring Global Settings for CFM
- Configuring Interfaces for CFM
- Configuring CFM Maintenance Domains
- Configuring CFM Maintenance Associations
- Configuring Maintenance End Points
- Configuring Remote Maintenance End Points
- Transmitting Link Trace Messages
- Transmitting Loop Back Messages
- Transmitting Delay-Measure Requests
- Displaying Local MEPs
- Displaying Details for Local MEPs
- Displaying Local MIPs
- Displaying Remote MEPs
- Displaying Details for Remote MEPs
- Displaying the Link Trace Cache
- Displaying Fault Notification Settings
- Displaying Continuity Check Errors
- OAM Configuration
- UDLD Configuration
- LBD Configuration
- Smart Pair Configuration
- Multicast Filtering
- Overview
- Layer 2 IGMP (Snooping and Query for IPv4)
- Configuring IGMP Snooping and Query Parameters
- Specifying Static Interfaces for a Multicast Router
- Assigning Interfaces to Multicast Services
- Setting IGMP Snooping Status per Interface
- Filtering IGMP Query Packets and Multicast Data
- Displaying Multicast Groups Discovered by IGMP Snooping
- Displaying IGMP Snooping Statistics
- Filtering and Throttling IGMP Groups
- MLD Snooping (Snooping and Query for IPv6)
- Multicast VLAN Registration for IPv4
- Multicast VLAN Registration for IPv6
- Basic IP Functions
- IP Configuration
- General IP Routing
- IP Services
- Appendices
- Glossary
Chapter 12
| Security Measures
DHCPv4 Snooping
– 368 –
◆ TCP-SYN/FIN Scan – A TCP SYN/FIN scan message is used to identify listening
TCP ports. The scan uses a series of strangely configured TCP packets which
contain SYN (synchronize) and FIN (finish) flags. If the target's TCP port is
closed, the target replies with a TCP RST (reset) packet. If the target TCP port is
open, it simply discards the TCP SYN FIN scan. (Default:
Disabled)
◆ TCP Xmas Scan – A so-called TCP XMAS scan message is used to identify
listening TCP ports. This scan uses a series of strangely configured TCP packets
which contain a sequence number of 0 and the URG, PSH and FIN flags. If the
target's TCP port is closed, the target replies with a TCP RST packet. If the target
TCP port is open, it simply discards the TCP XMAS scan. (Default:
Disabled)
Web Interface
To protect against DoS attacks:
1. Click Security, DoS Protection.
2. Enable protection for specific DoS attacks.
3. Click Apply
Figure 229: Protecting Against DoS Attacks
DHCPv4 Snooping
The addresses assigned to DHCPv4 clients on insecure ports can be carefully
controlled using the dynamic bindings registered with DHCPv4 Snooping (or using
the static bindings configured with IPv4 Source Guard). DHCPv4 snooping allows a
switch to protect a network from rogue DHCPv4 servers or other devices which
send port-related information to a DHCPv4 server. This information can be useful in
tracking an IPv4 address back to a physical port.
Command Usage
DHCP Snooping Process
◆ Network traffic may be disrupted when malicious DHCP messages are received
from an outside source. DHCP snooping is used to filter DHCP messages
received on a non-secure interface from outside the network or fire wall. When
DHCP snooping is enabled globally and enabled on a VLAN interface, DHCP