QoS

QUALITY OF SERVICE · PART 1 packetlife. net Quality of Service Models Best Effort · No QoS policies are implemented Integrated Services (IntServ) · Resource Reservation Protocol (RSVP) is used to reserve bandwidth per flow across all nodes in a path... More

QUALITY OF SERVICE · PART 1 packetlife. net Quality of Service Models Best Effort · No QoS policies are implemented Integrated Services (IntServ) · Resource Reservation Protocol (RSVP) is used to reserve bandwidth per flow across all nodes in a path Differentiated Services (DiffServ) · Packets are individually classified and marked; policy decisions are made independently at each node in a path Layer 2 QoS Markings Medium Name Type Ethernet Class of Service (CoS) 3-bit 802. 1p field in 802. 1Q header Frame Relay Discard Eligibility (DE) 1-bit drop eligibility flag ATM Cell Loss Priority (CLP) 1-bit drop eligibility flag MPLS Experimental Field (EXP) 3-bit field compatible with 802. 1p IP QoS Markings Precedence · The first three bits of the IP TOS field are evaluated; compatible with Ethernet CoS and MPLS EXP values DSCP · The first six bits of the IP TOS are evaluated to provide more granular classification; backward-compatible with IP Precedence QoS Flowchart Terminology Per-Hop Beha Less