Log in to ask questions, share your expertise, or stay connected to content you value. Don’t have a login? Learn how to become a member.
Question What is the queuing buffer size on MX Series DPCs? Answer On port queuing DPCs, the delay buffer is 100 ms per port on egress. This delay calculation is based on a 64 byte average packet size. On Enhanced Queuing DPCs, the delay buffer is 500 ms per port on egress and ingress
Answer Use traffic-manager mode with the following options to configure CoS traffic manager mode of operation: egress-only—Enables CoS queuing and scheduling on the egress side for the PIC that houses the interface. This is the default mode for an Enhanced Queuing (EQ) DPC on MX Series routers. ingress-and-egress—Enables CoS queuing and scheduling on both the egress and ingress sides for the PIC. This is the default mode for IQ2 and IQ2E PICs on M Series and T Series routers. For EQ DPCs, you must configure the traffic-manager statement with ingress-and-egress mode to enable ingress CoS on the EQ DPC. By default, ingress CoS features are disabled on EQ DPCs. EQ DPCs support ingress queuing
Question Which classification methods are supported for ingress queuing on an Enhanced Queuing Dense Port Concentrator (EQ-DPC) on MX Series routers? Answer Support for ingress queuing on EQ-DPC includes the following methods, as defined in Institute of Electrical and Electronics Engineers (IEEE) 802.1p: IP Differentiated Services code point (DSCP) precedence for IPv4 interfaces MPLS EXP for MPLS interfaces Tagged VPLS, bridge, and circuit cross-connect (CCC) interfaces There is no support for ingress queuing for untagged VPLS and CCC interfaces. DSCP is not supported as a classification option for ingress queuing on VPLS interfaces
Question How is the shaping rate calculated on the Enhanced Queuing DPCs (DPCE-R-Qs)? Answer The shaping rate calculation on the Enhanced Queuing DPC is similar to the shaping rate and WRR calculations performed on the Gigabit Ethernet IQ2 PICs: For ingress and egress: Layer 3 header + Layer 2 header + frame check sequence (FCS) For more information, see MX Series Interface Module Reference #FAQ #JuniperMXSeries #enhancedqueuingDPCs
Question What are the QoS properties of the Enhanced Queuing DPCs (DPCE-R-Q)? Answer Support ingress queuing, scheduling, and shaping Classification using EXP for VPLS without tunnel ACL-based classification for ingress QoS Layer 2 policers: per-VLAN ingress policers and per-VLAN egress policers Match 802.1p and PLP in a firewall filter Rewrite inner packets 802.1p Rate limit per queue Includes DEI7 bit in 802.1p-based classification Double the number of subscribers, schedulers, shapers, and queues per DPC Multiple VLAN bundling (interface sets within interface sets) Class-aware hierarchical policers For more information, see MX Series Interface Module Reference #enhancedqueuingDPC #FAQ #JuniperMXSeries