Netgear GS752TXS - Stackable Smart Gigabit Ethernet Switch 사용자 설명서
Chapter 5: Configuring Routing
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GS752TXS Smart Switch Software Administration Manual
Configuring ARP
The address resolution protocol (ARP) associates a layer 2 MAC address with a layer 3 IPv4
address. GS752TXS Smart Switch software features both dynamic and manual ARP
configuration. With manual ARP configuration, you can statically add entries into the ARP
table.
address. GS752TXS Smart Switch software features both dynamic and manual ARP
configuration. With manual ARP configuration, you can statically add entries into the ARP
table.
ARP is a necessary part of the internet protocol (IP) and is used to translate an IP address to
a media (MAC) address, defined by a local area network (LAN) such as Ethernet. A station
needing to send an IP packet must learn the MAC address of the IP destination, or of the next
hop router, if the destination is not on the same subnet. This is achieved by broadcasting an
ARP request packet, to which the intended recipient responds by unicasting an ARP reply
containing its MAC address. Once learned, the MAC address is used in the destination
address field of the layer 2 header prepended to the IP packet.
a media (MAC) address, defined by a local area network (LAN) such as Ethernet. A station
needing to send an IP packet must learn the MAC address of the IP destination, or of the next
hop router, if the destination is not on the same subnet. This is achieved by broadcasting an
ARP request packet, to which the intended recipient responds by unicasting an ARP reply
containing its MAC address. Once learned, the MAC address is used in the destination
address field of the layer 2 header prepended to the IP packet.
The ARP cache is a table maintained locally in each station on a network. ARP cache entries
are learned by examining the source information in the ARP packet payload fields,
regardless of whether it is an ARP request or response. Thus, when an ARP request is
broadcast to all stations on a LAN segment or virtual LAN (VLAN), every recipient has the
opportunity to store the sender’s IP and MAC address in their respective ARP cache. The
ARP response, being unicast, is normally seen only by the requestor, who stores the sender
information in its ARP cache. Newer information always replaces existing content in the ARP
cache.
are learned by examining the source information in the ARP packet payload fields,
regardless of whether it is an ARP request or response. Thus, when an ARP request is
broadcast to all stations on a LAN segment or virtual LAN (VLAN), every recipient has the
opportunity to store the sender’s IP and MAC address in their respective ARP cache. The
ARP response, being unicast, is normally seen only by the requestor, who stores the sender
information in its ARP cache. Newer information always replaces existing content in the ARP
cache.
The GS752TXS switches support 1024 ARP entries, which includes dynamic and static ARP
entries.
entries.
Devices can be moved in a network, which means the IP address that was at one time
associated with a certain MAC address is now found using a different MAC, or may have
disappeared from the network altogether (i.e., it has been reconfigured, disconnected, or
powered off). This leads to stale information in the ARP cache unless entries are updated in
reaction to new information seen on the network, periodically refreshed to determine if an
address still exists, or removed from the cache if the entry has not been identified as a
sender of an ARP packet during the course of an ageout interval, usually specified via
configuration.
associated with a certain MAC address is now found using a different MAC, or may have
disappeared from the network altogether (i.e., it has been reconfigured, disconnected, or
powered off). This leads to stale information in the ARP cache unless entries are updated in
reaction to new information seen on the network, periodically refreshed to determine if an
address still exists, or removed from the cache if the entry has not been identified as a
sender of an ARP packet during the course of an ageout interval, usually specified via
configuration.
Use the following web pages to configure and display ARP detail:
ARP Cache
Use the ARP Cache page to view entries in the ARP table, a table of the remote connections
most recently seen by this switch.
most recently seen by this switch.
To display the page: