Redes

1 a) Interfaces existentes:
Eth0 e lo;

b)Endereço MAC: Endereço de HW 00:27:13:ae:18:17
IP: inet end.: 200.17.210.249
Broadcast:200.17.210.255
Masc:255.255.255.0
MTU:1500

2)ARP
ARP antes
? (200.17.210.80) em 00:04:96:40:ac:60 [ether] em eth0

B) IP 200.17.210.248
MAC 00:27:13:ae:0c:db

ARP depois:
? (200.17.210.80) em 00:04:96:40:ac:60 [ether] em eth0
? (200.17.210.248) em 00:27:13:ae:0c:db [ether] em eth0

A tabela arp mudou porque nela são armazenados os endereços IP recentemente usados. As máquinas agora se “conhecem”.

3) TCPDUMP arp antes -200.17.210.249

listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
08:31:23.651177 00:27:13:ae:18:17 > ff:ff:ff:ff:ff:ff, ethertype ARP (0x0806), length 42: Request who-has 200.17.210.248 tell 200.17.210.249, length 28

08:31:23.651480 00:27:13:ae:0c:db > 00:27:13:ae:18:17, ethertype ARP (0x0806), length 60: Reply 200.17.210.248 is-at 00:27:13:ae:0c:db, length 46

08:31:28.666266 00:27:13:ae:0c:db > 00:27:13:ae:18:17, ethertype ARP (0x0806), length 60: Request who-has 200.17.210.249 tell 200.17.210.248, length 46

08:31:28.666277 00:27:13:ae:18:17 > 00:27:13:ae:0c:db, ethertype ARP (0x0806), length 42: Reply 200.17.210.249 is-at 00:27:13:ae:18:17, length 28
^C
4 packets captured
4 packets received by filter
0 packets dropped by kernel

Resposta Arp root@camyla-DSI:/home/camyla# arp -an
? (200.17.210.80) em 00:04:96:40:ac:60 [ether] em eth0
? (200.17.210.248) em 00:27:13:ae:0c:db [ether] em eth0

4)PING root@camyla-DSI:/home/camyla# ping -c 1 200.17.210.248
PING 200.17.210.248 (200.17.210.248) 56(84) bytes of data.
64 bytes from 200.17.210.248: icmp_req=1 ttl=64 time=0.678 ms

--- 200.17.210.248 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.678/0.678/0.678/0.000 ms

Com a resposta, é possível saber que o pacote foi transmitido com sucesso.

TCPDUMP