Applications for an Independent

Transcription

1 APPLICATION NOTE Applications for an Independent Control Plane Juniper Networks Control System Application Note Copyright 2009, Juniper Networks, Inc.

2 Table of Contents Introduction Scope Description and Deployment Scenario Shared Versus Independent Control Plane Overview of Key Applications for Network Consolidation Carrier of Carrier Applications Route Reflection and Dedicated GP Processing Rapid Service Rollout Potential Future Applications Summary Appendix A: References arketing Collateral Documentation Appendix : Frequently Asked Questions How Does Affect Day to Day Operations? Describe the Transition Process from Current Architecture to Architecture How Does Change Power and Space Usage in the POP? About Juniper Table of Figures Figure 1: Shared Versus Independent Control Plane Figure 2: Creation of a Protected System Domain: Routing Engines on and Line Cards on T Figure 3: Router Connectivity with Figure 4: Consolidate Networks (Vertical) or Functions (Horizontal) Figure 5: Consolidating Separate Networks Figure 6: Carrier of Carrier Deployment with Figure 7: Partitioned Route Reflectors Supporting ultiple Sets of s Figure 8: Applications ade Possible y Juniper Products on the Three Planes ii Copyright 2009, Juniper Networks, Inc.

3 Introduction In the networking industry, the forwarding capacity of routers continues to increase at a pace that rivals oore s Law with single chassis routers now in the terabit range. However, with most of the attention going to the forwarding capacity when comparing products, the importance of the control plane is often overlooked. The control plane capacity of a router is equally critical, as it must scale to accommodate routing and forwarding tables, service tunnels, virtual networks, and other information related to network construction and its optimal usage. The importance of control plane scale magnifies in a modern converged infrastructure. Service providers are called upon to deliver innovative capabilities to multiple customer segments. Delivering varied services concurrently across a converged IP/PLS infrastructure means that any individual service may contend for a fixed amount of control plane capacity on any individual router. Enabling an infrastructure s control plane to scale independent of its forwarding capacity eliminates this restriction, and it provides a control plane multiplicity (separate control plane per service) that enables services, virtualized networks, and forwarding capacity to all grow separately. This greatly increases flexibility and sharply reduces risk for service providers, and thus represents the next logical step in the evolution of routing technology. In essence, this concept of virtual service networks delivers on the promise of network convergence by decoupling services from the infrastructure on which they are provisioned. Scope After explaining the key concepts of an independent control plane, this application note discusses key applications for the Juniper Networks Control System, along with additional opportunities for this high-capacity computing platform with the Juniper Networks JUNOS Software development toolkit made available through the Partner Solution Development Program (PSDP). Description and Deployment Scenario There are key differences between a shared and an independent control plane. They are described below. Shared Versus Independent Control Plane y removing the tight coupling between control and forwarding planes of a router, we allow each to have new degrees of freedom to scale and innovate. This provides ultimate flexibility in a network buildout. You can scale customers, sessions and services on the one hand, traffic on the other, and neither control nor traffic scaling will be dependent on the other. With a shared control plane, as new services are added, the processing requirements increase and the likelihood of one service affecting another also increases; therefore, the overall stability of the system may be affected. For instance, if you have an IP service, a virtual private LAN service (VPLS), and an service running on the same router, the routing tables, service tunnels and other logical circuits are scaled together, and at some point will combine to exceed limits that each would not reach alone. When introducing new services in this environment, you need to perform compound scaling and regression testing in both the lab and in the field and determine how these services are affecting each other. With an independent control plane, such as the, assigned to each service (or at least to services with high control plane scale), your risk in rolling out a service is greatly reduced. The scaling and stability constraints of any individual service do not affect the others, and the processing requirements remain stable. Copyright 2009, Juniper Networks, Inc. 1

4 Figure 1 illustrates the contrast between the use of a shared and an independent control plane. SHARE CONTROL PLANE INDEPENDENT CONTROL PLANE SVC 1 SVC 2 SVC 3 SVC n SVC 1 SVC 2 SVC 3 SVC n CONTROL PLANE CP1 CP2 CP3 CPn FORWARDING PLANE FORWARDING PLANE Router Router Stability Processing Requirements Scale Stability Scale Processing Requirements SVC 1 SVC 2 SVC 3 SVC n SVC 1 SVC 2 SVC 3 SVC n Figure 1: Shared Versus Independent Control Plane Figure 2: Creation of a Protected System Domain- Routing Engines on and Line Cards on T1600 Overview of is a chassis accommodating up to twelve Routing Engines (REs) and connecting to one or more Juniper routers, enabling the creation of up to six dual-re control plane domains (essentially, hardware-virtualized routers), twelve single-re control plane domains, or any combination of the two. ecause the system provides purpose-built slots for the REs, all of the high-throughput slots on routers can be used for forwarding. High-bandwidth uplinks can be shared, and interconnections between the hardware-based logical routers called Protected System Domains (PSDs) can be created on the backplane with no need for physical interfaces. Figure 2 illustrates how a creates PSDs when combined with a Juniper Networks router. Routing engines on the are assigned to forwarding cards on the Juniper router (in this case, a Juniper Networks T1600 Core Router), forming the protected system domain (PSD). Each PSD can have its own administration/management domain in order to support scenarios where multiple teams are managing the network. These PSDs have full JUNOS Software capability with the same look and feel of a physical router. They provide isolation and availability and have the ability to run different software versions. You can also connect multiple routers to a. With the routing engines on the router, you create a Root System Domain (RSD), which provides a global view of the physical assets on the router and the, and allows you to create, modify and delete PSDs. For more information, see the Protected System Domain Configuration Guide (link in References section below). 2 Copyright 2009, Juniper Networks, Inc.

5 It is instructive to look at the physical connections as well. The, as shown below, has an internal switching system for communication between the routing engines and the forwarding planes of the client routers. The connections from the to the Juniper router are Gigabit Ethernet (GbE) connections to the control board. The router s control board controls the communication between the control and forwarding planes of the router. Key Applications for When you are able to create multiple control and forwarding planes that are unrestricted by hardware constraints, you can essentially create separate virtual service networks that decouple the services from the infrastructure. This allows true network convergence, and lowers both CAPEX and OPEX with a single physical network supporting multiple services. The simplified architecture yields reduced risk, which means that you can be much more confident in your service level agreements. Sample applications include network consolidation and collapsed point of presence (POP) architectures, carrier of carrier networks, accelerated service rollout, and high capacity route reflectors. Network Consolidation One of the key applications for is the ability to virtualize the architecture and consolidate either networks (for instance, a voice and a network), or network functions (such as core and aggregation routing). Network consolidation provides a number of financial advantages. The most obvious advantage is the reduction of capital investment (CAPEX). Rather than building a number of separate infrastructures to support separate services, you are investing in a single infrastructure. And just as importantly, you are investing in a single type of equipment. CAPEX is further reduced because expensive WAN links and their supporting interfaces are shared; service-specific networks require separate, dedicated links within each network. RE m RE b RE m ROUTER Router Internal LAN Routing Engine Routing Engine Control oard External LAN Switch RE b RE m RE b Control oard Switch RE m RE b SI ackup Plane A SI RE m SI SI Plane Plane C Plane D Fabric ASIC SI SI Internal LAN RE b RE m RE b SI Switch Fabric for Data SI Figure 3: Router Connectivity with Copyright 2009, Juniper Networks, Inc. 3

6 While CAPEX reduction is the most apparent benefit, reduction in operational expenses (OPEX) is a large financial benefit of network consolidation as well. While separate areas of specialization are still required to operate multiple services, the diversity of specialization is much less: the common technologies of the consolidated infrastructure means your operations staff can also be consolidated, reducing personnel, training and management costs. Consolidation further reduces OPEX by reducing the amount of rack space and power consumed. For many operators, the reduced real estate and power budget requirements have proven to be a very compelling benefit of network consolidation. Finally, network consolidation enables the quick development and rollout of new services (discussed below). The elimination of the need to fund and build a service-specific infrastructure means a new service can go from conception to rollout in 9 to 18 months. As Figure 4 shows, there are different ways to consolidate with an independent control plane. VoIP Video Core Edge Vertical Consolidation VoIP VoIP Video Video Core Edge Horizontal Consolidation Integrated Core and Edge Router Figure 4: Consolidate Networks (Vertical) or Functions (Horizontal) In vertical consolidation, you consolidate networks: in this case, VoIP, video, and access. In horizontal consolidation, you consolidate network functions: in this case, edge and core functions. 4 Copyright 2009, Juniper Networks, Inc.

7 Figure 5 shows another example of both vertical and horizontal consolidation. Separate and networks are being consolidated into a single physical network, with a separate control plane for each service. Furthermore, the aggregation and core network functions are also collapsed into single physical routers. AGG Core AGG Core Figure 5: Consolidating Separate Networks Collapsing a POP in this way greatly reduces the total number of interconnects in the topology, and also results in savings on chassis, blades and power. The total CAPEX savings in a typical medium-sized POP is on the order of 30 percent, and consolidating resources in this way results in even greater operational savings over time. Note: There is a configuration example for consolidating Layer 2 networks in the Protected System Domain Configuration Guide. See the References appendix at the end of this application note for the link to that manual. Copyright 2009, Juniper Networks, Inc. 5

8 Carrier of Carrier Applications Consolidation principles are also being used by carriers needing to provide access or sell bandwidth to local service providers. Instead of dedicating a peering router for one customer, you can use the same infrastructure to peer with multiple customers, or to sell bandwidth to multiple carriers. y dedicating separate control plane and forwarding plane resources for each customer, you can safely do this and maintain the necessary isolation that each peering entity will require. GP Control Plane Independent, Redundant Routing Engines CONTROL Peers, ISP s A C A C A C PEs PEs Forwarding Plane - Separate Line Cards - Separate Ports CONTROL Figure 6: Carrier of Carrier Deployment with In Figure 6, three separate peers (A, and C) are being supported with peering routers, and instead of devoting a separate peering router for each, they can be handled together in separate PSDs. The s are each controlling the redundant peering routers. There is complete isolation on the forwarding plane: separate line cards, interfaces and connections. Interfaces can be separated or shared. Route Reflection and Dedicated GP Processing GP route reflectors are essential for the management of large scale GP networks, as they maintain an internal GP mesh between routers in an autonomous system. And when a service provider s customer base grows, the distribution of tables to multiple route reflectors is critical to the practical scaling of the supporting network. Route reflectors do not need to be on the forwarding paths of a network, and therefore do not require highperformance forwarding; they require only a control plane and enough forwarding plane connectivity to send and receive GP messages from their peers. allows you to create a multiple instance route reflector. Within a single network area served by a POP, you can subdivide your edge services or customers, and for each of these subdivisions assign a control plane master/ backup pair (an instance). In this way, you can partition the route reflector function so that each instance supports a range of customers. Note: any route reflector deployments use geographical redundancy rather than local master/backup redundancy. 6 Copyright 2009, Juniper Networks, Inc.

9 In Figure 7, each route reflector instance supports a range of customer s. As you add more s, you can add more control plane instances. Platform Platform RR1 RR1 RR2 RR2 RR3 RR3 RR4 RR4 POP1 RR1 POP2 RR1 RR2 RR2 RR3 RR3 RR4 RR4 PE PE Figure 7: Partitioned Route Reflectors Supporting ultiple Sets of s In this example, there is both local and geographic redundancy. You have two route reflectors, each serving a specific area in the network. As compared to assigning separate edge routers for each of these customers, the CAPEX and OPEX savings can be over 50 percent, due to the lack of an unnecessary forwarding function and the administrative ease of controlling route reflection from a dedicated control plane device. Rapid Service Rollout When introducing a new service into an existing consolidated network, independent control planes provide a huge reduction in the processes required to qualify the service. This is due to the elimination of compound service scaling tests, both in the lab and in the field. Separate control planes simplify debugging and problem resolution, and reduce impact to existing services during field trials. For example, consider the rollout of a business edge service such as VPLS being added to a network that is already running IP s and perhaps connections. When you have to test the scaling of routing tables, customer connections and other service parameters together, it quickly becomes hard to determine why scaling limits are being exceeded. With, this problem goes away. Copyright 2009, Juniper Networks, Inc. 7

10 Taking sample network parameters of 50 POPs and 50 GbE connections at each POP, and working with customers who support services such as these, we determined that a rollout with to separate the services results in the service going live in 7 as opposed to 11 months a four month improvement (35 percent). If you consider a cost of $12,000 per GbE port, this time-to-market advantage quickly translates into faster time-to-revenue, as shown in Table 1. Table 1: Time to arket Advantages of a Rapid Service Rollout Accelerated Revenue OPEX CAPEX Four month improvement in service velocity 25% Take rate $30 50% Take rate $60 75% Take rate $90 100% Take rate $120 5 percent reduction for two initial services. OPEX savings will grow as new services are added. Up to 30 percent reduction for two initial services (reduction in common equipment). Long-term CAPEX savings will accelerate as new The potential revenue at this number of ports, POPs and GbE connections can be quite high, and as such, the CAPEX savings can be quite significant. Potential Future Applications With the advent of content, application and handset providers all providing services and traffic that traverse backbones service providers need to negotiate on technical and business levels to capture value from the tidal wave of traffic that is washing over the core from the edge. A scalable, independent control plane is a key part of the solution to this emerging environment, because it enables individualized tracking of customers and services without affecting other traffic. Service providers have long established, through the research efforts of IPsphere and IS (among other forums), that a three-layer model including (1) applications and services, (2) policy and control, and (3) packet forwarding is the optimal way to tackle these challenges. In addition to a high-performance, independent control plane, Juniper believes that allowing partners to augment the operating system with a software developer kit (SDK) is the ideal way to provide the toolset that providers need on the services plane. The following table lists some of the tools at each layer of the model that will provide the basis for exciting next-generation applications. Table 2: usiness Evolution Tools on the Application, Control and Forwarding Planes Application/Service Plane Path Computation Content Insertion Content Optimization Control and Policy Plane IP/PLS Customer Profiles Policy Enforcement Forwarding Plane Dynamic Filters Routing and Switching Active Services Engines Sampling Engines 8 Copyright 2009, Juniper Networks, Inc.

11 The following figure shows a sampling of the applications that are made possible by Juniper products on the three planes. Applications PLS Core HD Video multicast at scale Network consolidation (collapsed POP architectures) Control: Service: PSDP Service separation (equal access) Accelerated service rollout High capacity route reflectors Service-aware SLA monitoring Forwarding: T1600 Real-time ad insertion Access control Path computation Summary Figure 8: Applications ade Possible y Juniper Products on the Three Planes Needless to say, there are many more applications possible with this sophisticated toolset. These include applications such as dynamic path computation, real-time engineering of service tunnels, and content insertion/ optimization, as well as proprietary control plane applications such as load-based and audience-based routing protocols or content-driven routing schemes at terabit speeds. In many cases, the possibilities will be dictated by the requirements and expertise of the individual service provider. Key applications benefitting from control plane independence include network virtualization and consolidation, carrier of carrier services, route reflection, and rapid service prototyping and rollout. Consolidated networks can save up to 30 percent on CAPEX, and independent route reflectors can save on the order of 50 percent. The time-tomarket advantages of the service acceleration with an independent control plane are substantial, and can result in huge amounts of accelerated revenue. Furthermore,, used in conjunction with openness in the network operating system via an SDK, provides a complete three-layer network stack in the service, control and forwarding dimensions. This combination, realized with Juniper routers, and the PSDP, provides the complete toolset for creating exciting new applications in service networking s emerging business models. Appendix A: References The following sections provide additional reference material on. arketing Collateral Control Plane Scaling and Router Virtualization: Data Sheet: Secure Router Virtualization Critical Solutions for Optimizing IP/PLS Network Convergence: Synergy Research Group Case Study on the : Copyright 2009, Juniper Networks, Inc. 9

12 Documentation The documentation is available at: It includes the following manuals: Release Notes Hardware Guide Quick Start Protected System Domain Configuration Guide Appendix : Frequently Asked Questions About Juniper The following are frequently asked questions about. How Does Affect Day to Day Operations? In general, this depends on the way that is used. If it is being used as a control plane scaling system, it does not change operations at all. If you are dividing the control plane into multiple instances, then of course each instance might be managed by a different group. You might have, for example, an edge group managing edge instances and a core group managing core instances. Describe the Transition Process from Current Architecture to Architecture You move the configuration from the RE on the router to the RE on. When you add to a network, you are adding control plane resources to what you already have in place. You can use existing control plane resources as well. How Does Change Power and Space Usage in the POP? You use the for the added control plane capacity the alternative would be just to add more routers. In general, the use of should result in more efficient use of power and space in the POP. Juniper Networks, Inc. is the leader in high-performance networking. Juniper offers a high-performance network infrastructure that creates a responsive and trusted environment for accelerating the deployment of services and applications over a single network. This fuels high-performance businesses. Additional information can be found at Corporate and Sales Headquarters Juniper Networks, Inc North athilda Avenue Sunnyvale, CA USA Phone: 888.JUNIPER ( ) or Fax: APAC Headquarters Juniper Networks (Hong Kong) 26/F, Cityplaza One 1111 King s Road Taikoo Shing, Hong Kong Phone: Fax: To purchase Juniper Networks solutions, please contact your Juniper Networks representative at or authorized reseller. EEA Headquarters Juniper Networks Ireland Airside usiness Park Swords, County Dublin, Ireland Phone: Fax: Copyright 2009 Juniper Networks, Inc. All rights reserved. Juniper Networks, the Juniper Networks logo, JUNOS, NetScreen, and ScreenOS are registered trademarks of Juniper Networks, Inc. in the United States and other countries. JUNOSe is a trademark of Juniper Networks, Inc. All other trademarks, service marks, registered marks, or registered service marks are the property of their respective owners. Juniper Networks assumes no responsibility for any inaccuracies in this document. Juniper Networks reserves the right to change, modify, transfer, or otherwise revise this publication without notice EN ar 2009 Printed on recycled paper. 10