Is there a way to monitor packets on a LAN network?

[Soukuw]

Without installing Wireshark on all of the computers?

I need to be able to see the destination of them.

[Ad Bot]

[Doomonkey]

Use some trickery to make one computer the default gateway. Then rout all traffic from that computer to the real gateway. Only install Wireshark on the fake gateway.

[KoopaScooper]

I think DD-WRT has a feature like this but it only monitors lan packets coming from and to the computer apart from internet packets.

Use some trickery to make one computer the default gateway. Then rout all traffic from that computer to the real gateway. Only install Wireshark on the fake gateway.

You need to NICs to do this

[Doomonkey]

You need to NICs to do this

I'm pretty sure almost every computer has an integrated NIC.

The goal is essentially to perform a man-in-the-middle attack, but without being malicious.

[mp7964]

Wireshark.

[dorkdotdan]

Wireshark.

Someone obviously read the op.

[mp7964]

Someone obviously read the op.

You don't need to install it on all of the computers.

[Soukuw]

You don't need to install it on all of the computers.

Everything I can think of I searched in Google and all the links are purple you could do something really helpful for me by just explaining it beyond telling me I can.

[Trinick]

You would need to install it on all the computers. Sorry, but your router is the only computer that can do that. Unless you're up for rewriting your router's firmware, it's not really possible.

[KoopaScooper]

Unless you're up for rewriting your router's firmware

DD-WRT

[Trinick]

Also, I'm no router firmware expert but I doubt one type of firmware will work for every router.

[KoopaScooper]

Also, I'm no router firmware expert but I doubt one type of firmware will work for every router.

It doesn't work with every router, that's why it has a compatibility database to look up your router model for installation instructions.

[Wedge]

Forget modifying your router and use a passive network tap. Either buy one or build one. You install it in between your modem and switch/router.

Putting custom firmware on your router is fine and all, but unless you really lucked out you'll spend a lot of time digging through compatibility databases. If you plan on putting custom firmware on your router it's easier to just figure out what firmware you want, then buy that exact compatible model and version of router off ebay.