Open source software offers an economical and flexible option for deploying basic home, SMB or even enterprise networking. These open source products deliver simple routing and networking features, like DHCP and DNS. Plus, they are combined with security functionality, starting with a basic firewall and possibly including antivirus, antispam and Web filtering.
These products can be downloaded and deployed on your own hardware, on a virtual platform, or in the cloud. Many of them sell pre-configured appliances as well if you like their feature-set or support, but don’t want to build your own machine.