There are endless free and open source software solutions and services out there for use in the network\u2014for small, medium, and enterprise environments. You aren\u2019t limited to Microsoft, Cisco, and other commercial giants. You can save money by using free, open source, or less expensive solutions. Here I\u2019ll share a couple you might consider.<\/p>\n
Vyatta<\/a> is a network operating system targeted for enterprise-level networks for cloud, virtual, and physical deployments. It offers the core network services: NAT, routing, DHCP, firewall, VPN, QoS, IPS, and more. It can install onto any standard x86 based system, run using VMware, Citrix XenServer, Xen and Redhat KVM hypervisor environments, or on Amazon VPC. They provide their core open source software for free with documentation, but isn\u2019t recommended for critical networks. The paid subscriptions offer additional features, updates, add-ons, and support.<\/p>\n Endian<\/a> is a Unified Threat Management (UTM) operating system, enabling you to turn any PC or server into a full-featured security appliance. In addition to providing the basic LAN services (NAT, Firewall, DHCP, etc.), it also offers VPN, hotspot functionality, anti-virus, anti-spam, web security, and email content filtering. Like Vyatta, their free open source community version of the OS isn\u2019t designed for critical networks.<\/p>\n RouterOS<\/a> is a closed source Linux-based operating system (OS) designed to implement a router. It\u2019s the same OS offered on the Router BOARD hardware from MikroTik. However, the OS is freely downloadable and installable onto regular PCs and servers, turning it into an enterprise-level router. It offers all the network services for a LAN, including routing, firewall, bandwidth management, wireless access point, backhaul link, hotspot gateway, VPN server, and more. However, only basic functionality and limited use of some features is free. After the 24-hour fully functional trial, you can purchase a license starting at $45.<\/p>\n Untangle<\/a> is another network operating system, but is targeted more for small-to-medium sized businesses. It can be installed and ran on a normal dedicated PC. It can provide the router (with NAT, firewall, DHCP, etc.) for your network and\/or provide additional security and control, such as web and spam filtering, virus and spyware protection, captive portal, a VPN server. The paid premium services then offer enhancements to these features and additional user and bandwidth management functionality.<\/p>\n The 389 Directory Server<\/a>, previously known as the Fedora Directory Server, is a free and open Linux-based enterprise-class LDAP server. It can be an alternative solution to or compliment Microsoft\u2019s Active Directory. It supports install on Linux, Solaris, and HP\/UX 11 systems. It\u2019s highly reliable and scalable with multi-master replication. It features a graphical console for managing the server, users, and groups.<\/p>\n Citadel<\/a> is a Linux-based open source groupware solution to manage and offer email, calendar, contact management, and other collaboration features to your users. It\u2019s available as a Debian\/Ubuntu package, or downloaded as a VMware appliance. Users can access the services via a web-based interface or via supported clients, such as Outlook, Mozilla Thunderbird and Sunbird, Evolution, and KOrganizer.<\/p>\n SOGo<\/a> is another Linux-based open source groupware solution, offering email, calendar, and contact management to your users. Binary packages are available for several Linux distributions and it\u2019s available as virtual appliances. Unlike most other open source Groupware solutions, the connectors for Outlook and Thunderbird are available for free. Additionally, it also supports all the major mobile smartphones and devices, either natively or via a free SOGo connector.<\/p>\n OpenDNS<\/a> is a third-party DNS service you can use instead of your ISP\u2019s. It\u2019s a fast and intelligent DNS service that can protect against DNS-based attacks and malware\/botnet activity. Additionally, it can provide DNS-based content filtering to automatically block phishing, malware-infested, proxy, adult, and other dangerous sites. You can also view usage reports on Internet activity. It even features the ability to create shortcuts, or words you can type into a browser that will automatically point to a website or IP address.<\/p>\n FreeNAS<\/a> is one of the most popular open source network-attached storage (NAS) software solutions. It installs onto systems with a Compact Flash, USB flash, hard drive, or booted directly from a LiveCD. It offers sharing attached drives via following native protocols: SMB\/CIFS (Windows), AFP (Apple\/Mac), and NFS (Unix\/Linux). Additional supported protocols include FTP, TFTP, RSYNC, Unison, iSCSI and UPnP.<\/p>\n It supports advanced networking with VLAN tagging, link aggregation, and Wake on Lan (WoL). The monitoring features include S.M.A.R.T (smartmontools), email alerts, SNMP, Syslog, and UPS support. You\u2019ll also find extra services: bittorent client (Transmission), UPnP server (FUPPES), iTunes\/DAAP server (Firefly), webserver (lighttpd), and network bandwidth measure (Iperf).<\/p>\n Nagios<\/a> is a monitoring and alerting system to keep tabs on your servers, switches, applications, and services. It features a web-based interface, email and SMS alerts, escalation capabilities, and event handlers to automatically restart failed services. Reports can provide records of alerts, notifications, outages, and alert responses. The solution is also highly customizable and extendable via add-ons, APIs, or code modifications. You can use free open source version for solid monitoring, but they offer a separate version for enterprise-class environments.<\/p>\nEndian Enterprise-level Firewall\/Router<\/h2>\n
RouterOS Enterprise-level Firewall\/Router<\/h2>\n
Untangle SMB-level Firewall\/Router<\/h2>\n
389 Directory Server<\/h2>\n
Citadel for Email, Calendar, and Collaboration<\/h2>\n
SOGo for Email, Calendar, and Collaboration<\/h2>\n
OpenDNS for Fast and Intelligent DNS and Content Filtering<\/h2>\n
FreeNAS for a Network File Server<\/h2>\n
Nagios for Network Monitoring<\/h2>\n
DD-WRT Wi-Fi Router Firmware Replacement<\/h2>\n