GS-1524/GS-1548 User’s Guide
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Dynamic ARP
This chapter describes how to activate dynamic Address Resolution Protocol (ARP)
learning and how to enter static ARP table entries.
20.1 ARP Table Overview
Address Resolution Protocol (ARP) is a protocol for mapping an Internet Protocol
address (IP address) to a physical machine address, also known as a Media Access
Control or MAC address, on the local area network.
An IP (version 4) address is 32 bits long. In an Ethernet LAN, MAC addresses are
48 bits long. The ARP table maintains an association between each MAC address
and its corresponding IP address.
20.1.1 ARP Table Entries
The ARP table is populated with MAC and corresponding IP address mappings in
two different ways.
• DHCP Snooping - The Switch listens to traffic from a DHCP server on a trusted
port and learns IP-to-MAC address bindings by parsing DHCP ACK packets.
• Static Entries - The Switch administrator can enter static IP-to-MAC address
mappings via the web configurator.
20.1.2 How Dynamic ARP Works
When an incoming ARP packet destined for a host device on a local area network
arrives at the Switch, the Switch's ARP program looks in the ARP table and, if it
finds the address, sends it to the device.
If no entry is found for the IP address, dynamic ARP discards the ARP packet.
Summary of Contents for GS-1524
Page 2: ......
Page 8: ...Safety Warnings GS 1524 GS 1548 User s Guide 8 ...
Page 10: ...Contents Overview GS 1524 GS 1548 User s Guide 10 ...
Page 18: ...18 ...
Page 26: ...Chapter 2 Hardware Installation and Connection GS 1524 GS 1548 User s Guide 26 ...
Page 34: ...34 ...
Page 42: ...Chapter 4 The Web Configurator GS 1524 GS 1548 User s Guide 42 ...
Page 52: ...Chapter 6 Port Settings GS 1524 GS 1548 User s Guide 52 ...
Page 62: ...Chapter 8 VLAN GS 1524 GS 1548 User s Guide 62 ...
Page 82: ...Chapter 12 Port Rate Limit and Storm Control GS 1524 GS 1548 User s Guide 82 ...
Page 86: ...Chapter 13 Layer 2 L2 Management GS 1524 GS 1548 User s Guide 86 ...
Page 92: ...Chapter 15 Auto Denial of Service DoS GS 1524 GS 1548 User s Guide 92 ...
Page 96: ...96 ...
Page 136: ...Chapter 19 RMON Lite GS 1524 GS 1548 User s Guide 136 ...
Page 144: ...Chapter 21 Troubleshooting GS 1524 GS 1548 User s Guide 144 ...
Page 150: ...Chapter 22 Product Specifications GS 1524 GS 1548 User s Guide 150 ...
Page 152: ...152 ...
Page 166: ...Appendix B Legal Information GS 1524 GS 1548 User s Guide 166 ...