Control and understand how your Internet connection is being used. AllegroSurf allows you to use a single internet connection and share it with the rest of the computers on your network. AllegroSurf will also increase browsing speed by prefetching pages then loading them from cache when viewed later. Availability
Establish when a user or server is available.
Inbound / Outbound Transfer Rates
Create a transfer rate limit restricting the transfer rate to a reasonable value.
Inbound / Outbound Transfer Quotas
Restrict how much total data your users can transfer in a given time period. AllegroSurf supports these proxy protocols:

• SOCKS4, SOCKS4A, and SOCKS5
• HTTP
• POP3 & SMTP
• TCP mapping
• TCP port mapping
• TCP mapping and TCP port mapping using SSL
• NNTP (Network News Transfer Protocol)
• FTP
• RTSP (RealPlayer)
• DHCP
• DNS
• UDP mapping
• UDP port mapping
• Telnet
• SSL (Secure Socket Layer)

Free trial for Windows.