D-Link DGS-3630 User Manual 1 - Page 560

DGS-3630 Series Layer 3 Stackable Managed Switch Web UI Reference Guide Click the Clear by Protocol button to the clear the information based on the protocol selected. Click the Clear All button to clear all the information in this table. Click the Find button to locate a specific entry based on the information entered. Click the Show All button to locate and display all the entries. Safeguard Engine Periodically, malicious hosts on the network will attack the Switch by utilizing packet flooding (ARP Storm) or other methods. These attacks may increase the Switch's CPU load beyond its capability. To alleviate this problem, the Safeguard Engine function was added to the Switch's software. The Safeguard Engine can help the overall operability of the Switch by minimizing the workload of the Switch while the attack is ongoing, thus making it capable to forward essential packets over its network in a limited bandwidth. If the CPU load rises above the rising threshold value, the Safeguard Engine function will be activated and the Switch will enter the exhausted mode. In the exhausted mode, the Switch will limit the bandwidth available for ARP and broadcast IP packets. If the CPU load falls below the falling threshold value, the Safeguard Engine will be deactivated and the Switch will exit the exhausted mode and enter the normal mode. Packets that are destined to the CPU can be classified into three groups. These groups, otherwise known as subinterfaces, are logical interfaces that the CPU will use to identify certain types of traffic. The three groups are Protocol, Manage, and Route. Generally, the Protocol group should receive the highest priority when the Switch's CPU processes received packets and the Route group should receive the lowest priority as the Switch's CPU usually does get involved in the processing of routing packets. In the Protocol group, packets are protocol control packets identified by the router. In the Manage group, packets are destined to any router or system network management interface by means of interactive access protocols, like Telnet and SSH. In the Route group, packets are identified as traversing routing packets that is generally processed by the router CPU. In the following table a list of supported protocols are displayed with their respective sub-interfaces (groups): Protocol Name 802.1X ARP BGP DHCP DNS DVMRP GVRP ICMPv4 ICMPv6Neighbor ICMPv6-Other Sub-interface (Group) Protocol Protocol Protocol Protocol Protocol Protocol Protocol Protocol Protocol Protocol IGMP LACP NTP OSPF PIM PPPoE RIP Protocol Protocol Protocol Protocol Protocol Protocol Protocol Description Port-based Network Access Control Address resolution Protocol Border Gateway Protocol Dynamic Host Configuration Protocol Domain Name System Distance Vector Multicast Routing Protocol GARP VLAN Registration Protocol Internet Control Message Protocol IPv6 Internet Control Message Protocol Neighbor Discovery Protocol (NS/NA/RS/RA) IPv6 Internet Control Message Protocol except Neighbor Discovery Protocol (NS/NA/RS/RA) Internet Group Management Protocol Link Aggregation Control Protocol Network Time Protocol Open Shortest Path First Protocol Independent Multicast Point-to-point protocol over Ethernet Routing Information Protocol 548