CISCO SYSTEMS SOLUTIONS PRACTICAL JUNIPER NETWORKS AND SOLUTIONSJUNIPER BERRYJUNIPER BONSAI GUIDE PDF EBOOK EPUB MOBI. Interdomain Multicast Solutions Guide is a complete, concise, solutions-based book that shows how to deploy IP multicast services. The book. PDF | The tussle in IP multicast, where different enablers have interests that are our solution changes the traditional open multicast service model into a more IP Multicasting: The Complete Guide to Interactive Corporate Networks. Article.
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and Cisco Systems Solutions Interdomain Multicast Routing: Practical Juniper Guide To PhysicsIl Libro Completo Delle Aperture Apprendere Bene E. CCIE Routing and Switching Exam Certification arersnaperstif.cf 10M [ ] CCNP - Cisco Cisco Press - Interdomain Multicast Solutions arersnaperstif.cf M [ ] Cisco Press. interdomain multicast network implements SSM in its network using URD. scenario described in the “Interdomain Multicast Solutions Using MSDP” Cisco IOS IP and IP Routing Configuration Guide, Release
Since PIM-SM is commonly used in the initial sequence of activities that gets multicast up and running within a single domain, the procedure dominates the scope of this chapter. PIM messages for both version 1 and version 2 of the protocol are covered, as is the use of anycast rendezvous point RP to improve load balancing and redundancy.
Ample diagrams and corresponding examples describe distribution tree construction and teardown for various topologies, and the chapter ends with a discussion of multicast scoping. This chapter contains a number of illustrations of the rules that determine the reverse path forwarding RPF peer, a critical component in MSDP. Recognizing the paucity of clear information about MSDP peer-RPF rules, which are quite complex, the authors have provided detailed rule descriptions, as well as diagrams and realistic examples.
The chapter concludes with sections on mesh groups, susceptibility to operational problems, and a discussion of the prospects for the widely used MSDP vis a vis the upcoming version of Border Gateway Multicast Protocol BGMP. SSM, a recent addition to the ever-changing multicast routing landscape, holds the greatest amount of promise for deployment, considering that many believe the most dominant commercial use of Internet multicast will likely conform to a one-to-many model.
The remaining chapters of Interdomain Multicast Routing cover critical hands-on, real-world examples and tools. Chapter 11, "Case Study: Service Provider Native Deployment," provides a representative case study for native deployment of IMR by an Internet service provider; Juniper Networks and Cisco Systems router configurations for all router roles in this example network are also set forth.
RTP is suited to real-time applications such as video and audio streaming. Finally, because any new world of knowledge comes to be mastered only by intelligent use and definition of its key concepts, we spent a considerable amount of time gathering and refining pertinent terminology; we hope the Glossary clarifies key abbreviations, acronyms, and definitions and even serves to stimulate dialog leading to more exact rendering of terms in future iterations of the book. Acknowledgments The authors have been blessed with many excellent reviewers, ensuring our approach and description were accurate and unbiased.
Further, the authors would like to thank Karen Gettman and Emily Frey of Addison-Wesley for helping to guide us through the intricacies of turning manuscripts into printed works. We would also like to pause and acknowledge the support and assistance of Juniper Networks for allowing us to work on this project and to occasionally use corporate resources.
Finally, the authors, individually, would like to thank the following friends, family, peers, and coworkers for their fortitude and inspiration: Brian Edwards wants to thank the following people because each has provided a tremendous amount of support and guidance throughout his life and professional career: Christine Hatchett, Mabry and Linda Edwards, John Madding, Sr.
Leonard A. Giuliano first thanks his loving wife, Hallie, along with his parents and sisters for their endless support and encouragement. Brian Wright especially salutes his coauthors for their practical contributions to the development of IMR, as well as their idea that a hands-on book on the subject would be worthwhile.
Thanks to the aforementioned first-rate talent at Juniper Networks and Addison-Wesley. Interdomain Multicast Fundamentals This chapter introduces and describes the fundamental concepts of multicast.
Subsequent chapters build upon these concepts, illustrating how they are specifically used in the protocols and technologies that enable the operation of interdomain multicast. This chapter also defines terms and conventions that will be used throughout the book. The three main methods of data delivery are unicast, broadcast, and multicast.
These methods are summarized as follows: Unicast: Data is delivered to one specific recipient, providing one-to-one delivery. Broadcast: Data is delivered to all hosts, providing one-to-all delivery. Multicast: Data is delivered to all hosts that have expressed interest. This method provides oneto-many delivery. The Internet was built primarily on the unicast model for data delivery see Figure However, unicast does not efficiently support certain types of traffic.
Figure Unicast delivery Multicast, originally defined in RFC by Steve Deering, provides an efficient method for delivering traffic that can be characterized as "one-to-many" or "many-to-many. With unicast, a radio station would have to set up a separate session with each interested listener. A duplicate stream of packets would be contained in each session. The processing load and the amount of bandwidth consumed by the transmitting server increase linearly as more people tune in to the station.
This might work fine with a handful of listeners; however, with hundreds or thousands of listeners, this method would be extremely inefficient. With unicast, the source bears the burden of duplication. Using broadcast see Figure , the radio station would transmit only a single stream of packets, whether destined for one listener or for one million listeners. The network would replicate this stream and deliver it to every listener. Unfortunately, people who had not even tuned in to the station would be delivered this traffic.
This method becomes very inefficient when many uninterested listeners exist. Links that connect to uninterested end hosts must carry unwanted traffic, wasting valuable network resources. With broadcast, the network carries the burden of delivering the traffic to every end host. Broadcast delivery Multicast, on the other hand, provides the best of both worlds without introducing the disadvantages of each see Figure Multicast enables the radio station to transmit a single stream that finds its way to every interested listener.
As in the case of broadcast, the processing load and the amount of bandwidth consumed by the transmitting host remain constant, regardless of audience size. The network is responsible for replicating the data and delivering it only to listeners who have tuned in to the station. Links that connect to uninterested listeners do not carry the traffic. This method provides the most efficient use of resources because traffic flows only through links that connect to end hosts that want to receive the data.
Multicast delivery To deliver data only to interested parties, routers in the network build a distribution tree. Each subnetwork that contains at least one interested listener is a leaf on the tree. When a new listener tunes in, a new branch is built, joining the leaf to the tree. When a listener tunes out, its branch is pruned off the tree.
Where the tree branches, routers replicate the data and send a single flow down each branch. Thus no link ever carries a duplicate flow of packets. With multicast, the source is not burdened because it must transmit only a single stream of data, and the network is not burdened because it must deliver traffic only to end hosts that have requested it.
However, in the zero-sum world of networking, where nothing is free, the burden of multicast falls on network engineers who must design and manage the mechanisms that make it work!
Throughout the book we use the slash notation for bit mask when describing IP address ranges. The slash notation indicates how many bits of the address remain constant throughout the range of addresses. For example, The range is from address We also make reference to classful networks. Class B networks: Describe the range of networks from Class C networks: Describe the range of networks from Originally, networks were assigned to organizations along classful boundaries.
Classful allocation was inefficient because organizations that required slightly more than addresses could be assigned an entire class B. Classless interdomain routing CIDR enabled the assignment and routing of addresses outside of classful boundaries. All multicast addresses fall in the class D range of the IPv4 address space.
The class D range is Multicast addresses do not have a mask length associated with them for forwarding purposes. We use shorter mask lengths on multicast addresses in some parts of the book for reasons other than forwarding.
These masks generally are used to describe ranges of multicast addresses. We refer throughout the book to unicast and multicast routing protocols. Unicast routing protocols are used by routers to exchange routing information and build routing tables. IGPs provide routing within an administrative domain known as an autonomous system AS. EGPs provide routing between ASs.
Multicast routing protocols are used by routers to set up multicast forwarding state and to exchange this information with other multicast routers. The terms control packets and data packets are used to differentiate the types of packets being routed through the network.
Control packets include any packets sent for the purpose of exchanging information between routers about how to deliver data packets through the network. Control packets are typically protocol traffic that network devices use to communicate with one another to make such things as routing possible.
Data packets use the network to communicate data between hosts; they do not influence the way the network forwards traffic. Letters delivered via postal mail are analogous to data packets. Information exchanged between post offices to describe what ZIP codes mean is analogous to control packets.
A group member is a host that expresses interest in receiving packets sent to a specific group address. A group member is also sometimes called a receiver or listener. A multicast source is a host that sends packets with the destination IP address set to a multicast group.
A multicast source does not have to be a member of the group; sourcing and listening are mutually exclusive. Because there can be multiple receivers, the path that multicast packets take may have several branches. A multicast data path is known as a distribution tree. Data flow through the multicast distribution trees is sometimes referenced in terms of upstream and downstream. Downstream is in the direction toward the receivers. Upstream is in the direction toward the source.
A downstream interface is also known as an outgoing or outbound interface; likewise, an upstream interface is also known as an incoming or inbound interface. Routers keep track of the incoming and outgoing interfaces for each group, which is known as multicast forwarding state.
The incoming interface for a group is sometimes referred to as the IIF. The outgoing interface list for a group is sometimes referred to as the OIL or olist. The OIL can contain 0 to N interfaces, where N is the total number of logical interfaces on the router. The IP header of the multicast data packet contains S as the packet's source address.
The "G" represents the specific multicast group IP address of concern. The IP header of the multicast data packet contains G as the packet's destination address. So for a host whose IP address is A multicast group can have more than one source.
If two hosts are both acting as sources for the group In general, routers make unicast routing decisions based on the destination address of the packet. When a unicast packet arrives, the router looks up the destination address of the packet in its routing table.
The routing table tells the router out from which interface to forward packets for each destination network. Unicast packets are then routed from source to destination. In multicast, routers set up forwarding state in the opposite direction of unicast, from receiver to the root of the distribution tree. Routers perform a reverse path forwarding RPF check to determine the interface that is topologically closest to the root of the tree see Figure RPF is a central concept in multicast routing.
In an RPF check, the router looks in a routing table to determine its RPF interface, which is the interface topologically closest to the root. The RPF interface is the incoming interface for the group. If a router learns that an interested listener for a group is on one of its directly connected interfaces, it tries to join the tree for that group.
In Figure , this router somehow knows the IP address of the source of this group. The RPF check tells the router which interface is closest to the source.
The router now knows that multicast packets from this source to this group should flow into the router through this RPF interface. Shortest path tree SPT The router sends a Join message out the RPF interface to inform the next router upstream it wants to receive packets for this group from this source. This message is an S,G Join message. This upstream router sends an S,G Join message out its RPF interface for the source informing its upstream router that it wants to join the group.
Each upstream router repeats this process of propagating Joins out the RPF interface until this new branch of the tree either a reaches the router directly connected to the source or b reaches a router that already has multicast forwarding state for this source-group pair.
In this way, a new branch of the tree is created from receiver to source. Once this branch is created and each of the routers has forwarding state for the source-group pair, multicast packets can flow down the tree from source to receiver. In a shared tree, the root of the distribution tree is a router somewhere in the core of a network.
In Figure 16, this router does not know the address of the source of this group. However, it does know that another router in the network is aware of the source. The router that somehow knows the sources for all multicast groups is the RP we will find out just how it knows this in Chapters 2 and 3. It needs to know only a that the RP should know the source and b how to get to the RP.
Each upstream router repeats this process of propagating Joins out of the RPF interface until this new branch of the tree either a reaches the RP or b reaches a router that already has multicast forwarding state for the group along the RPT. In this way, a new branch of the tree is created from receiver to RP. For now, it is most important to understand the concept of reverse path forwarding. In either case, this RPF table contains only unicast routes. It does not contain multicast group addresses because RPF checks are performed only on unicast addresses either the source or the RP.
If a dedicated multicast RPF table is used, it must be populated by some other means. Routes can be tagged as multicast RPF routes and thus distinguished from unicast routes. The advantage of having a dedicated RPF table is that a network administrator can set up separate paths and policies for unicast and multicast traffic. Financial institutions have applications, such as stock tickers, that require sharing the same data across the network.
Using unicast for these applications is inefficient and not cost effective. Likewise, some enterprise networks serve companies with applications ideally suited to multicast deliveryfor example, a central headquarters that must feed hundreds of branch sites with price lists and product information. Transferring these identical files to all sites individually with unicast simply is not efficient. In the past, enterprise networks have frequently looked much different than the networks managed by Internet service providers ISPs.
This difference existed because these networks had to meet a set of radically different requirements. Enterprise networks connect the offices of a single company, which often involves transporting primarily a single type of data for example, file transfer. Transporting only a single type of data enables the network to be built in a way that optimizes delivery of that type of traffic. Also, few, if any, of the routers in an enterprise network connect to routers controlled by another entity.
ISP networks couldn't be more different. ISPs can have up to thousands of different customers, each a separate administrative entity. The data can include an unclassifiable mix of voice, video, e-mail, Web, and so on. Providing ubiquitous support for these various traffic types across the interdomain world of the Internet has always set ISPs apart from enterprises in the way they are designed and operated.
Unicast and multicast routing on enterprise and financial networks has often involved deploying protocols and architectures that best meet the needs of the companies they connect.
These protocols and architectures often do not address the scalability and interdomain requirements of ISPs. However, recent trends have shown that the networking needs of enterprises have evolved to more closely resemble those of ISPs.
Accordingly, many enterprise networks today are beginning to use the same principles and philosophies found in the engineering of ISPs' networks, albeit on a smaller scale.
The focus of this book is to describe the technologies and challenges faced by ISPs when deploying and operating multicast across the Internet. The first reason for this focus is neglect.
Most networking books concentrate on enterprise networks rather than the unique demands of service provider networks. Second, ISP networks generally possess the superset of requirements that are found on other types of networks. For example, financial networks typically need to support many-to-many applications. Other enterprise networks may need to support only one-to-many applications.
Because ISPs may be delivering service to both types of networks, they must be equipped to handle both types of applications.
Additionally, ISP networks have scalability demands that are rarely found on any other types of networks. While ISPs continue to have unique requirements for scalability and interdomain stability, most of the same multicast technologies found in ISP networks can be applied for use on other networks.
By adopting these ISP philosophies, financial and enterprise networks are capable of ubiquitously supporting all types of multicast traffic. However, as this draft specifies an implementation that precedes the standardization multicast cisco [ MVPN ] by several years, it does differ multicast cisco a few respects from a fully standards-compliant implementation.
These differences are pointed out where they occur. This document extends that specification by specifying the necessary protocols and procedures for support of IP multicast.
This specification presupposes that: Familiarity with the terminology and procedures of [ RFC ] is presupposed.
Familiarity with [ PIMv2 ] is also presupposed. This optimal routing multicast cisco provided without requiring the P routers to maintain any routing information that is specific to a VPN; indeed, the P routers do not maintain any per-VPN state at all. Optimal multicast routing would require that one or more multicast distribution trees be created in the backbone for each multicast cisco group that is in use. If a particular multicast group from within a VPN is using source-based distribution trees, optimal routing requires that there be one distribution tree for each transmitter of that group.
If shared trees are being used, one tree for each group is still required. Cisco customers who use IOS documentation have requested more robust and more complete configuration examples to help in their day-to-day implementation of IOS. ISDs provide concise design and application information, explaining multicast cisco to integrate specific feature functionality within an existing network environment.
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He holds multicast cisco B.