ARP entries

[RTK513]

Hello...new to networking and learning about ARP. I'm trying to figure out whats happening here when I do the following;

C:\>ipconfig


Windows NT IP Configuration


Ethernet adapter El90x1:


IP Address. . . . . . . . . : 10.0.0.98
Subnet Mask . . . . . . . : 255.255.0.0
Default Gateway . . . . : 10.0.255.254






C:\>arp –a


Interface: 10.0.0.98 on Interface 2
Internet Address Physical Address Type
10.0.255.254 00-e0-b0-ac-ac-a8 dynamic






C:\>ping 10.0.255.255


Pinging 10.0.255.255 with 32 bytes of data:


Reply from 10.0.255.255: bytes=32 time<10ms TTL=255
Reply from 10.0.255.255: bytes=32 time<10ms TTL=255
Reply from 10.0.255.255: bytes=32 time<10ms TTL=255
Reply from 10.0.255.255: bytes=32 time<10ms TTL=255






C:\>arp –a


Interface: 10.0.0.98 on Interface 2
Internet Address Physical Address Type
10.0.116.21 00-00-f4-a9-9d-d4 dynamic
10.0.224.34 00-00-1d-0f-4b-71 dynamic
10.0.108.2 00-00-f4-a9-98-21 dynamic
10.0.17.129 00-00-f4-b1-b6-57 dynamic
10.0.7.141 00-10-5a-05-ef-f9 dynamic
10.0.0.153 00-60-b0-79-c3-80 dynamic
10.0.3.3 00-e0-34-8b-2f-ff dynamic
10.0.1.250 00-00-0c-4e-32-90 dynamic
10.0.1.251 00-00-0c-4e-32-90 dynamic
10.0.255.252 00-e0-b0-ac-ac-a8 dynamic
169.254.0.1 00-00-09-6c-4b-58 dynamic

Why are there new entries after I ping 10.0.255.255? Is it because it's dynamic?
Why are 10.0.1.250 and 10.0.1.251 and 169.254.0.1 listed?

 

[office politics]

im guessing new entries are added because you're pinging a broadcast address. this should attempt to ping all nodes on that subnet. dynamic is listed becasue that's how the entriy was added in the arp cache. another type of entry could be static; where you would add it manually.

as you contact more nodes on the network, entries are added dynamically to the cache.

 

[ph4nt0m117]

From what I see.... It looks like you're pinging.... Yourself?

Aside from that bit of confusion it seems that the new entries are as said, being added from a broadcast address (aka - you). Little bit of knowledge that I have about networking in total I can't answer this wholesomely, but more give a question to you. Have you taken note that the gateway ends in 254? That may give a separate result. Also what are you trying to accomplish here?