Firewall > QoS Mapping
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SonicOS Enhanced 4.0 Administrator Guide
• Shaping – An attempt by a QoS system to modify the rate of traffic flow, usually by
employing some feedback mechanism to the sender. The most common example of this is
TCP rate manipulation, where acknowledgements (ACKs) sent back to a TCP sender are
queued and delayed so as to increase the calculated round-trip time (RTT), leveraging the
inherent behavior of TCP to force the sender to slow the rate at which it sends data.
• Type of Service (ToS) – A field within the IP header wherein CoS information can be
specified. Historically used, albeit somewhat rarely, in conjunction with IP precedence bits
to define CoS. The ToS field is now rather commonly used by DiffServ’s code point values.