Since the publication of the first edition of this book, several new packages have been added. The most notable of these new packages are as follows:

• acme: A package which automates the process of generating Let's Encrypt certificates. The goal of Let's Encrypt is to encrypt the web by making it easier to obtain SSL certificates. acme stands for Automated Certificate Management Environment.
• frr: The FRR routing daemon for BGP, OSPF, and OSPF6. This package is intended to supersede Quagga OSPF, although the latter has not been removed from the package list or deprecated. It is not compatible with OpenBGPD or Quagga OSPF.
• lldpd: Provides support for the Link Layer Discovery Protocol (LLDP), which is specified in IEEE 802.1ab. It also provides support for several proprietary protocols, such as Cisco Discovery Protocol (CDP), Extreme Discovery Protocol (EDP), Foundry Discovery Protocol (FDP), and Nortel Discovery Protocol (NDP/SONMP).
• net-snmp: A GUI for snmpd and snmptrapd which, unlike the built-in bsnmpd daemon, supports Simple Network Management Protocol (SNMP) version 3 as well as IPv6. 
• telegraf: An agent written in Go (a compiled, statically-typed programming language similar to C) for collecting, processing, and writing metrics.
• tftpd: A package that installs and runs a TFTP (Trivial File Transfer Protocol) server. 

To the best of my knowledge, no existing packages have been deleted or deprecated between the release of pfSense 2.3 and 2.4. Of the newer packages, FRR seems to be the most significant, and will be covered in this section.