Netgear GS728TXS GS728TXS/GS752TXS Software Administration Manual - Page 303

GS752TXS and GS728TXS Smart Switches There are two basic types of QoS: • Integrated Services. Network resources are apportioned based on request and are reserved (resource reservation) according to network management policy (RSVP, for example). • Differentiated Services. Network resources are apportioned based on traffic classification and priority, giving preferential treatment to data with strict timing requirements. The GS752TXS and GS728TXS Smart Switches supports DiffServ. The DiffServ feature contains a number of conceptual QoS building blocks you can use to construct a differentiated service network. Use these same blocks in different ways to build other types of QoS architectures. There are 3 key QoS building blocks needed to configure DiffServ: • Class • Policy • Service (i.e., the assignment of a policy to a directional interface) Class You can classify incoming packets at layers 2, 3, and 4 by inspecting the following information for a packet: • Source/destination MAC address • EtherType • Class of Service (802.1p priority) value (first/only VLAN tag) • VLAN ID range (first/only VLAN tag) • IP Service Type octet (also known as: ToS bits, Precedence value, DSCP value) • Layer 4 protocol (such as TCP or UDP) • Layer 4 source/destination ports • Source/destination IP address From a DiffServ point of view, there are two types of classes: • DiffServ traffic classes • DiffServ service levels/forwarding classes 303