Networks. Characteristics of IP. Internet overview Service Router Service Aggregation Router Ethernet Service Switch

Transcription

1 1 IP/MPLS Service Networks The Alcatel-Lucent NRS II exam topics covered in this chapter include the following: Characteristics of IP Internet overview Alcatel-Lucent 7750 Service Router product group 7750 Service Router 7705 Service Aggregation Router 7450 Ethernet Service Switch 7210 Service Access Switch

2 In this chapter, we describe the development of the Internet and the characteristics of the Internet protocol (IP). We see how IP networks have evolved and the requirements of networking technology today. Multiprotocol Label Switching (MPLS) addresses some of the limitations of IP networking and provides a foundation for building service networks. The chapter concludes with an overview of the Alcatel-Lucent Service Router product group. 1.1 Internet Protocol Development of the Internet protocol (IP) started in 1974 and was formally defined in RFC 791 ( Request for Comments for Internet Protocol ) published in TCP/IP (Transmission Control Protocol/Internet Protocol) became the standard protocol of the ARPANET (Advanced Research Projects Agency Network) on January 1, 1983 many consider this the birth of the Internet. The NSFNET (National Science Foundation Network) was created in 1986 with backbone links of 56 kb/s; these were soon upgraded to 1.5 Mb/s. Incredibly, today we re deploying links that support 100,000 Mb/s, and we re still using the same version of IP! Characteristics of IP The phenomenal growth of the Internet to date is to some extent a result of the characteristics of IP. Some of the characteristics that lead to IP s global dominance are the following: Simplicity This is the most important characteristic contributing to the success of IP. It means that new hardware and software supporting IP are easily developed, more easily deployed, and more easily managed. Simplicity also leads to lower cost, another characteristic of IP networks. Accessibility This is also a very important contributing factor to the success of IP. Development of the first Internet standards was an open and collaborative process, an approach that has continued to this day. All standards documents are freely available and usually easy to understand. In an age when the only question is whether to use IPv4 or IPv6, it s easy to forget that 20 years ago there were many different communications protocols in use, and most were proprietary. The OSI (Open System Interconnect) protocols were open, but the standards documents were expensive, complex, and difficult to follow, making them much less accessible than IP. 4 Chapter 1 n IP/MPLS Service Networks

3 Resiliency This was one of the original design goals for IP and was achieved through the connectionless nature and simplicity of the protocol. IP routing protocols react quickly to changes in the network topology and simply change the nexthop to which they forward packets for a particular destination. It is understood that IP provides an unreliable, connectionless service, thus the higher-layer protocols provide connection-oriented features as required. The simplicity of IP results in some serious limitations as the Internet reaches a size, complexity, and diversity of applications that was unimaginable to the early developers of the protocol. Some of the major shortcomings of IP include the following: Traffic engineering This is the ability to use a more sophisticated approach to routing traffic across the network. IP uses a simple hop-by-hop approach to forward traffic across the most direct path, but for today s networks and applications, this is often not the most suitable route. Traffic engineering allows for the use of other criteria and knowledge of the complete topology of the network to find an optimal path for a varied mix of traffic types. Quality of service (QoS) This is the ability to prioritize different traffic types and provide a different service level to each. Usually these service levels relate to delivery and delay guarantees. For example, a voice-over-ip application used for a real-time conversation requires a small delay and relatively low packet loss, whereas an e mail application can tolerate much greater delay and can easily retransmit lost packets. A simple IP network provides the same level of service to all applications (best effort). High resiliency High resiliency, or high availability, goes beyond the resiliency of IP to provide connectivity that is nearly always on. We can build redundancy into a network with IP routing protocols so that most equipment failures result in an outage lasting only a few seconds. We hardly notice such an outage when surfing the Web or sending e mails, but we are not nearly as tolerant when using IP-TV (broadcast television over IP) to watch our favorite sporting event. More demanding applications typically strive for failover in less than 50 milliseconds 1/20 of a second. IPv4 address space The IPv4 address space is effectively exhausted. The number of devices connected to the Internet continues to grow exponentially, and every one needs a unique address. There are measures that have been developed to extend the IPv4 address space, but ultimately the increased address space of IPv6 is required. 1.1 Internet Protocol 5

4 QoS is a topic for another book, but this book addresses the other three issues listed above. A key technology in adding these capabilities to an IP network is Multiprotocol Label Switching (MPLS). We will see that MPLS is effectively a tunneling technology that allows us to build a variety of different networks using the base technology of an IP network. Although the global, public Internet is the network that interconnects us all, in reality there is an even larger demand for private networks. These private networks may interconnect corporate enterprises to their different geographical locations or to their partners and customers. Or they may be used to deliver specific services in a controlled manner, such as mobile services or IP-TV delivery. Service providers are increasingly adopting IP/MPLS networks to provide these private network services. IP/MPLS provides a cost-effective, flexible foundation for deploying a wide variety of private network services. The Internet The 1980s were really the experimental years of the Internet as it grew throughout universities and American research institutions. TCP/IP was included in the free UNIX distributions of the time, which definitely helped spread the understanding and use of TCP/IP. The fact that the RFC documents that define all Internet protocols are freely available and generally easy to understand also helped spread its acceptance. Key characteristics of the Internet in the 1980s were the following: Experimental nature of the Internet Development of IP routing software (IS-IS, OSPF, BGP) Routing typically handled by general-purpose mini-computers running routing software During the 1990s, the Internet spread into the commercial world and a much broader public awareness. Major characteristics of this decade included the following: Development of the Hypertext Transfer Protocol (HTTP) and the World Wide Web Availability of high-speed Internet access using ADSL (Asymmetric Digital Subscriber Line) and cable networks Purpose-built routers including specialized hardware designed specifically for IP forwarding 6 Chapter 1 n IP/MPLS Service Networks

5 Exponential growth in size and bandwidth of the Internet Maturation of BGP (Border Gateway Protocol) In the first decade of the new millennium, the Internet spread beyond the relatively simple domain of e mail and web traffic into new domains with more demanding requirements. Characteristics of the first decade of 2000 included the following: Continued massive bandwidth increases The YouTube phenomena ubiquitous video and massive amounts of user-generated content Support of data services in the mobile network The introduction of MPLS to create a more sophisticated service layer over IP Routers capable of providing quality of service differentiation in an IP network What can we expect in the second decade of the new millennium? More of the same and then some: Continued massive bandwidth increases The cloud our data and applications moving to the network Video everywhere Greatly enhanced control plane for network components to improve and simplify management of the network Everything anywhere by the end of the decade, everything we manufacture will connect to the Internet, and we ll have access to it from anywhere. 1.2 Alcatel-Lucent 7750 Service Router Product Group The original Alcatel-Lucent Service Router was the Alcatel-Lucent 7750 SR, introduced in Since that time, other products have been added to the Service Router product family, all built around the SR-OS (SR Operating System) and all managed by the 5620 SAM (Service Aware Manager). Two of the products, the Alcatel-Lucent 7750 SR and the Alcatel-Lucent 7450 ESS, use FP network processors developed in-house to ensure leading-edge performance, density, and advanced services, with no compromise between speed and advanced service delivery. The 7750 SR was conceived and developed specifically for IP/MPLS Virtual Private Network (VPN) services such as Virtual Private Wire Services (VPWS), 1.2 Alcatel-Lucent 7750 Service Router Product Group 7

6 Virtual Private LAN Service (VPLS), and Virtual Private Routed Network (VPRN). The system architecture, hardware, and software fully support the provisioning and configuration of IP/MPLS networks with Layer 2 and Layer 3 VPN services. The SR product group supports a wide range of access interfaces. Broadly, these include the following: Ethernet interfaces from 100 Mb/s to 100 Gb/s Packet over SONET/SDH (POS) from OC-3c/STM-1c to OC-192c/STM-64c Circuit Emulation Service (CES) at OC-3/STM-1 and OC-12/STM-4 Asynchronous Transfer Mode (ATM) at OC-3c/STM-1c and OC-12c/STM-4c The primary focus of the Service Router product group is the IP services market. This covers a broad range of IP routers and switches from small hardened devices in a remote cell site to very large routers in a central office (CO) routing thousands of connections and terabits of data into the service provider core network. Although many edge routers today are simple IP routers, service providers are increasingly recognizing the benefits of deploying IP/MPLS service routers to support the diverse connectivity requirements and applications in today s network. Three key areas where IP/MPLS service routing is finding application today are the following: Residential service delivery This requires the reliable delivery of video, voice, and high-speed Internet services over an IP network. The network must provide differentiated quality of service to different traffic types and efficiently manage the service parameters for thousands of subscribers. Mobile Packet Core and backhaul This is evolving to a fully IP-based packet network. The mobile backhaul must support the increasing demand for data in existing mobile networks in a cost-effective manner while providing a path to support the deployment of fourth-generation LTE (Long Term Evolution) networks. Business service delivery This must provide cost-effective connectivity and bandwidth options while supporting legacy technologies. A reliable and secure service is required with defined and measured service level guarantees. Not all of the routers in the SR product group support all the features and capabilities of the 7750 SR, but all use the same core operating system and the same commandline interface (CLI) commands for configuring and managing the network. All the examples and exercises in this book were created on the 7750 SR but will function the 8 Chapter 1 n IP/MPLS Service Networks

7 same way on any other router in the product group, except in the circumstances in which it does not support the specific feature. In the sections below, we provide a brief introduction and overview of the members of the SR product family at the time of writing (June 2011). The four major product families in the Service Router product group are the following: 7750 Service Router 7705 Service Aggregation Router 7450 Ethernet Service Switch 7210 Service Access Switch 7750 Service Router The Alcatel-Lucent 7750 Service Router (SR) portfolio is a suite of multiservice routers that deliver high-performance, high-availability routing with service-aware operations, administration, management, and provisioning. The 7750 SR integrates the scalability, resiliency, and predictability of MPLS along with the bandwidth and economics of Ethernet and a broad selection of legacy interfaces, to enable a converged network infrastructure for the delivery of next-generation services. The 7750 SR s advanced and comprehensive feature set enables it to be deployed as a Broadband Network Gateway (BNG) for residential services, as a Multiservice Edge (MSE) for Carrier Ethernet and IP VPN business services, as the aggregation router in mobile backhaul applications, or as a mobile packet core for 2G, 3G, and LTE wireless networks. With support for service-enabled, high-density 10GigE, 40 GigE, and 100GigE interfaces, the 7750 SR is well suited for edge and core routing applications. The 7750 SR is available in four chassis variants, as shown in Figure 1.1, and scales gracefully from 90 Gb/s to 2 Tb/s of capacity. From left to right with the 7750 SR-7c in the foreground, the routers are as follows: 7750 SR SR SR-12c 7750 SR-7c 1.2 Alcatel-Lucent 7750 Service Router Product Group 9

8 Figure Service Router product family Service Aggregation Router The Alcatel-Lucent 7705 SAR portfolio is optimized for multiservice adaptation, aggregation, and routing, especially onto a modern Ethernet and IP/MPLS infrastructure. It is available in compact, low-power consumption platforms delivering highly available services over resilient and flexible network topologies. The 7705 SAR is well suited to the aggregation and backhaul of 2G, 3G, and LTE mobile traffic providing cost-effective scaling and the transformation to IP/MPLS networking. Business services modernization is supported in the transition from legacy to consolidated, packet-based operation. Hugely reduced equipment footprints are achievable with reduced energy costs. Industries, enterprises, and government organizations can achieve reliable and resilient support of legacy and advanced services. The 7705 SAR is available in three chassis variants: 7705 SAR SAR SAR-F 10 Chapter 1 n IP/MPLS Service Networks

9 The 7705 SAR family in Figure 1.2 shows the SAR-F, the SAR-8, and the SAR-18, front to back. Figure SAR family Ethernet Service Switch The 7450 ESS is a highly scalable platform designed to support residential service delivery, business VPN services, and mobile backhaul applications at the Carrier Ethernet service edge. The 7450 ESS integrates the scalability, resiliency, and predictability of MPLS, along with the bandwidth and economics of Ethernet, to enable a metro-wide, converged packet aggregation infrastructure using Carrier Ethernet to deliver next-generation services. 1.2 Alcatel-Lucent 7750 Service Router Product Group 11

10 Designed as a service delivery platform, the 7450 ESS enables a broadly scalable service offering based on MPLS-enabled Carrier Ethernet. Comprehensive Carrier Ethernet and IP/MPLS feature and protocol support allows a full complement of residential, business, and mobile service applications across a range of topologies, from point-to-point to any-toany, from fully meshed to ring-based. The 7450 ESS enables providers to flexibly offer any combination of Ethernet or IP-based services in a highly scalable (up to 2 Tb/s) platform that can support hundreds of thousands of end users in a metro area with ease. The 7450 ESS is available in four chassis variants: 7450 ESS ESS ESS ESS-6v The ESS family in Figure 1.3 shows the ESS-7 on the left and the ESS-6 on the right with the ESS-12 behind. Figure ESS family. 12 Chapter 1 n IP/MPLS Service Networks

11 7210 Service Access Switch The Alcatel-Lucent 7210 SAS (Service Access Switch) family of compact, Ethernetedge, and aggregation devices enables the delivery of advanced Carrier Ethernet services to the customer edge and extends the reach of MPLS-enabled Carrier Ethernet aggregation networks into smaller network locations. Available in a wide range of compact form factors, the 7210 SAS enables fixed and wireless service providers, multiservice operators (MSOs), as well as industry and enterprise customers to build out cost-optimized Carrier Ethernet infrastructure for business, residential, and mobile services delivery. The 7210 SAS family is available in a range of platform variants, including two that support extended temperature ranges (ETRs). The current variants are the following: 7210 SAS-X 7210 SAS-M (10GigE and 10GigE ETR) 7210 SAS-M 7210 SAS-E 7210 SAS-D (SAS-D and SAS-D ETR) Figure 1.4 shows the 7210 SAS-E (on top) and the 7210 SAS-M. Figure SAS-E and SAS-M Service Aware Manager (SAM) The Alcatel-Lucent 5620 SAM (Service Aware Manager) provides end-to-end serviceaware management of all-ip networks and the services they deliver, going well beyond 1.2 Alcatel-Lucent 7750 Service Router Product Group 13

12 the traditional boundaries of element- and network-management systems. The 5620 SAM manages all network domains end-to-end as well as the multiple interdependent layers on which service delivery depends. With unified element, network, and serviceaware management, service providers can more effectively manage mobile, business, and residential services. The 5620 SAM consists of four integrated modules: 5620 SAM Element Manager (SAM-E) The 5620 SAM Element Manager (SAM-E) module provides traditional Fault, Configuration, Accounting, Performance, and Security (FCAPS) management functionality for element management and is the base platform for all 5620 SAM modules SAM Provisioning (SAM-P) The 5620 SAM Provisioning (SAM-P) module provides network configuration and service provisioning SAM Assurance (SAM-A) The 5620 SAM Assurance (SAM-A) module provides physical, network, and service topology views; and operations, administration, and maintenance (OAM) service-diagnostics tools SAM OSS Integration (SAM-O) The 5620 SAM OSS Integration (SAM-O) module provides an open interface for integration with external applications and operations support systems (OSSs). The 5620 SAM provides extensive management for all the products in the 7750 Service Router product group as well as many others in the Alcatel-Lucent High Leverage Network. 14 Chapter 1 n IP/MPLS Service Networks

13 Chapter Review Now that you have completed this chapter, you should be able to: List the key strengths and weaknesses of IP. Describe the overall evolution of the Internet. List the product families making up the Alcatel-Lucent Service Router product group. Chapter Review 15

14