Packets

Almost all network traffic is in the form of radio signals, more commonly referred to as packets. With the right tools, it is possible to intercept, craft, and forge your own signals for various purposes.

Packet Tools

Software

SigCatcher

The best way to find signals to decipher is with the program SigCatcher, available on the Network Tools disk. SigCatcher will snag any packet that the computer can detect-- either wired packets sent directly to that computer, or wireless packets when the wireless card is in mode free. The program only has a buffer for one signal at a time though, so you may need to check it frequently. It can run as a program in the background while you mess with other things. SigCatcher has two modes:

• on will display the last packet received.
• auto will grab the first packet it receives, then stops monitoring traffic, ensuring the packet is not overwritten by subsequent network activity.
• save will save the current signal as a file to your computer.
• quit will get you out of the program, but keep it running in the background.
• fquit will end the program entirely.

SigPal

Once you've started deciphering packets, you can begin to make your own using SigPal.

• Add [Key] [Data] is the core to setting up your packets. You need to have the right keys for other machines to understand what you're sending them.
• File lets you add a file to send.
• Remove If you make a mistake, you can't simply overwrite a line, you need to delete it, then add it back.
• New to clear the entire packet.
• View to view your current packet in its entirety.
• Save to save as a signal file.
• Load to load a signal file.
• Send to transmit the packet through the computer's network card.

FROG

Allows you to ping and connect to other terminals in a manner similar to DWAINE. Bear in mind that the Research Mainframe is on a physically separate network from the rest of the station. FROG will not recognize a wireless card.

Ping

Pings and records ping data. Also does not recognize a wireless card.

Hardware

Data Terminal

File:DataTerminal.png

This is the physical link to the wired network. A computer must be built on top of it to access that network. The most obvious and accessible data terminal is in Tech Storage, but many more can be found around the station, and they are under all of the existing ThinkDOS computers. The mechanics can make more, but must be able to properly wire them to the network.

Packet Sniffer

Found in Tech Storage. Capable of detecting all packets sent on the wired network it is attached to. Looks and functions like a powersink-- just screw it onto a data terminal and it will begin scanning. There is not much data on the main network of the station besides that which comes from the communications dish, but other interesting data may be found by setting up the sniffer on the Engineer or Research networks.

Network Diagnostics Cart

This cart can accomplish many of the same tasks as the network tools disk, but from your PDA. It features a ping tool, a packet sniffing tool, a packet sender, and a packet crafting tool. The range on the packet sniffer can be adjusted from close to far. The packet crafting tool does not have the 26 character string limit that SigPal does, allowing more complicated messaging.

Packet Formatting

A typical signal might look like this:

[command] [text_message]
[message] [What is your favorite pony]
[sender_name] [Weedgoku420]
[address_1] [02001921]
[sender] [02002276]

Each line of the signal consists of two items, the first item identifying the type of data, the second item identifying the actual data. This packet can be broken down as such:

[command] [text_message]
This tells the PDA that this command is a text message. This is just one of many commands available.

[message] [What is your favorite pony]
This is the text of the message. Note that a computer can handle a maximum of 26 characters.

[sender_name] [Weedgoku420]
This is what the sender's name will appear as in the message. No verification of this is done whatsoever, so the PDA will happily display whatever is written in the signal file. The limitation is again 26 characters.

[address_1] [02001841]
This is the network ID of the PDA the message will be going to.

[sender] [02002872]
This is the network ID of the PDA sending the message.

Any packet you send must have both a sender ID and an address. In mode net and on wired networks, the sender ID must correspond to your network module's number-- you can check that using the periph view command. Other data can be spoofed-- for instance, in sending a text message, you could change the sender name to whatever you want and make security think a Blob is somehow messaging them.