Local Broadcast and Directed Broadcasts - Demo and Packet Captures

In this video we'll pick apart Broadcasts -- specifically the difference between a Local Broadcast and a Directed Broadcast (which is sometimes referred to as a Targeted Broadcast).

We'll run through a few demonstrations of either type of broadcast. Then fire up Wireshark and take a look at the packets as they appear on the wire. This will illustrate clearly the difference between Layer 2 Broadcasts and Layer 3 Broadcasts.

This is the "long version" of this video. In the shorter version we simply talk through the concepts and do a couple ping tests.

00:00 - Start / Topology Introduction
00:22 - Definition of a Broadcast
00:47 - L2 Broadcast vs L3 Broadcast
01:35 - Local Broadcast
02:12 - Pinging the Local Broadcast
03:21 - Wireshark - Looking at a Unicast Ping
04:10 - Wireshark - Pinging the Local Broadcast IP address
05:18 - Directed Broadcast (Targeted Broadcast)
05:49 - Wireshark - Pinging the Directed Broadcast IP of the Local Subnet
08:34 - Directed Broadcasts for Foreign Networks
10:29 - Wireshark - Studying a Unicast ping to a foreign network
12:00 - Wireshark - Pinging the Directed Broadcast IP of a Foreign Subnet
13:57 - Directed Broadcast starts as Unicast, then becomes Broadcast
15:59 - Summary
16:34 - Security Implication of Directed Broadcasts
17:18 - Enabling Directed Broadcast on Cisco Routers and Linux Hosts
18:31 - Outro

Link to correlating article which includes PCAP files you can download:

https://www.practicalnetworking.net/s...