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Junos CoS on MX Series 5G Universal Routing Platforms Overview


The increased demand for sophisticated, media-rich services, the exponential growth of mobile sessions, and the emerging trend of cloud computing require a networking infrastructure that supports massive numbers of subscribers, service types and instances, and bandwidth. A number of features and methods have been developed to address these advanced network requirements, including Junos class of service (CoS). Junos CoS is a set of mechanisms that helps maintain specified service levels for your network by optimizing and prioritizing network traffic so that demand for resources can meet requirements. Use CoS mechanisms to control the allocation of network attributes such as available bandwidth, latency, jitter, packet drop, and bit rate errors so that resources are managed to levels acceptable to your network customers and applications.

CoS on Juniper Networks MX Series 5G Universal Routing Platforms

MX Series routers are available in a variety of configurations with robust features, including options that provide the level and granularity of the CoS support needed in your network. The MX Series hardware options include several models of Modular Port Concentrators (MPCs), using several different Modular Interface Cards (MICs), and several models of Dense Port Concentrators (DPCs). The MPCs and DPCs provide varying degrees of CoS support.

The MPCs are next-generation line modules for advanced Ethernet services edge and broadband edge networks using high capacity, modular Gigabit Ethernet, 10-Gigabit Ethernet, and 100-Gigabit Ethernet hardware. The MPCs house Packet Forwarding Engines that deliver comprehensive Layer 3 routing (IPv4 and IPv6), Layer 2 switching, inline services, and advanced hierarchical class of service (H-CoS) per MX Series slot. The MPCs can also take advantage of the high performance Junos Trio chipset.

Key CoS features provided by the MPCs include extensive queue management, scheduler hierarchy, shaping, intelligent oversubscription, weighted round robin (WRR), random early detection (RED), and weighted random early detection (WRED).

The DPCs (DPCE-X, DPCE-R, and DPCE-Q) each provide multiple physical interfaces and Packet Forwarding Engines on a single board that performs packet processing and forwarding. Each Packet Forwarding Engine consists of one I-chip for Layer 3 processing and one network processor for Layer 2. DPCE-Qs offer enhanced queuing capabilities and the CoS features of WRR, RED, and WRED.