S6E4: "Sliding Down a Series of Tubes"

Posted 2021-04-11 23:59
Modified 2021-04-11 13:36
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In this episode, we walk you through the basic procedure for sending a packet (or datagram) from its source to the destination!

• Just the Tip
• Notes
• 15 Clams
• Errata
• Music

Just the Tip

• Paden talks about LaZagne, which searches for passwords/credentials stored on your local system.
• He also mentions Ubiquiti’s major compromise and the drama ensuing.
  • We released a short public statement of our stance on this.

Notes

Starts at 25m15s.

I was drinking water. Paden was drinking Murphy’s Stout. Jthan was drinking Busch.

• A tour of packet/datagram’s path
  • First, imagine you’re a computer.
  • This process is a bit difficult to explain in text. So here are the basic steps:
    • If your target address is a DNS record, you need to first resolve the DNS record.
      • This has its own subset of the following processes (routing, etc.).
    • You now have an IP address of your destination. You can then route to it.
      • There are a couple different routing protocols, like OSPF and BGP.
    • Once you have a route, communication then occurs with your target. Further processes depend on the protocol and software involved:
      • For example, if it’s TCP, there’s a handshaking/session. If you’re using TLS over TCP, there’s an additional handshaking/session on top of that, etc.
  • The most important part is that first step – getting DNS resolvers and default gateway. Without having DNS resolvers (typically handled by DHCP for IPv4 and RA and/or DHCPv6 for IPv6), you cannot use domain names/other DNS records. Without a default gateway (again, typically handled by DHCP/RA/DHCPv6), you cannot send (or respond to!) packets from hosts outside of your own subnet (unless you had static routes for every single other network out there).

15 Clams

In this segment, Jthan shares with you a little slice of life. The title is a reference to this video. (2m16s in)

Starts at 52m01s.

Jthan wonders why/how AWS became the default for hosting.

Errata

• Technically a cube has to be the same on all six sides, Paden. ;)
• The IPv4 ranges reseverved for documentation can be found in RFC 5737. For IPv6, it can be found in RFC 3849.
• Passive-mode FTP is the one with the random port.

Music

Author r00t^2
Categories Season Six