0
votes
1answer
68 views

How can I connect to a router through a switched ethernet network?

I have a computer and a router connected at different positions to a switched ethernet network. I want to connect them as if I had plugged my computer directly into the router. As I understand it, ...
87
votes
13answers
10k views

What is the exact use of a MAC address?

I understand that IP addresses are hierarchical, so that routers throughout the internet know which direction to forward a packet. With MAC addresses, there is no hierarchy, and thus packet forwarding ...
3
votes
1answer
221 views

Relation between a packet and a frame over the network

I am learning how networks work and I have a question. What is actually sent over the network? A packet/datagram or a frame? I believe it is a packet. If so, let's say Computer A wants to communicate ...
1
vote
1answer
1k views

Planetlab and scapy: MAC address to reach destination not found

Using the minimal Fedora 14 distribution provided in PlanetLab, I'm forging packets through Scapy and sending them with tcpreplay. I thought I had installed all the necessary packages to run scapy ...
3
votes
4answers
3k views

Why do we need IP addresses to communicate within the local network segment?

Because MAC addresses are only usable across the local network segment, we use IP addresses to communicate with other segments via routers. Meanwhile, for local targets, ARP is used to translate IPs ...
0
votes
2answers
697 views

Discover the public ip of a network without being connected

Let say, I'm next to a network and can see the traffic (with airodump or similar tool) but can not decipher it (because I am not connected on the network). Is it possible to discover the public ip ...
1
vote
1answer
9k views

What does `Type: IP (0x0800)` in the Ethernet II part of a ping packet mean?

If I ping to another pc in my network I send a packet that consists out of an ICMP part, a IPv4 part and a Ethernet II part. I can see this using the packet analyser 'wireshark'. Now the Ethernet II ...
1
vote
2answers
395 views

Blocking or Disabling Rogue Routers

We have a medium sized network and from time to time something bad happens. Once it was a router configured to assign IPs via DHCP that did not match our network mask, thus making all clients unable ...
-2
votes
2answers
319 views

Is modifying our MAC Address a perfectly reversible operation?

Ok guys I've just read this page: http://www.irongeek.com/i.php?page=security/changemac But before I want to attempt anything, I want to ask: Is modifying our MAC Address (in the way provided at that ...
0
votes
1answer
1k views

How can I block a computer from my linksys router by IP or MAC address?

How can I block a computer (not on Wireless) from my linksys router by IP or MAC Address? I am using a linksys WAG200G.