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.All the server applications are on the mainframe computers and devices only requirehost access.APPN routing is not essential for this company.http://www.cisco.com/cpress/cc/td/cpress/ccie/ndcs798/nd2006.htm (57 of 59) [9/16/2000 5:06:44 PM] Designing APPN InternetworksFigure 6-34: APPN network with FRAS BNN.Implementing FRAS BNN rather than a full APPN network node on the access routers directly reducesthe number of network nodes.This allows the network to scale without the concern of TDU flows.Thisis proven to be a viable solution for this company for the time being because LAN-to-LAN connectivityis not an immediate requirement.The remote routers can be migrated to support APPN border node whenit becomes available.In this environment, CP-CP sessions are supported over the Frame Relay network.The central directoryserver and the concept of Connection Network are fully supported.LU-LU sessions can be set up usingthe direct route without traversing VTAM, as shown in Figure 6-34.The only function that is lost withFRAS BNN is COS for traffic traveling from the remote FRAS BNN router to the data center.SummaryRecall that this chapter discussed developing the network design and planning a successful migration toAPPN.It covered the following topics:Evolution of SNAWhen to Use APPN as Part of a Network DesignWhen to Use APPN Versus Alternative Methods of SNA Transporthttp://www.cisco.com/cpress/cc/td/cpress/ccie/ndcs798/nd2006.htm (58 of 59) [9/16/2000 5:06:44 PM] Designing APPN InternetworksOverview of APPNScalability IssuesBackup Techniques in an APPN NetworkAPPN in a Multiprotocol EnvironmentNetwork ManagementConfiguration ExamplesPosted: Thu Oct 28 16:44:23 PDT 1999Copyright 1989-1999©Cisco Systems Inc.http://www.cisco.com/cpress/cc/td/cpress/ccie/ndcs798/nd2006.htm (59 of 59) [9/16/2000 5:06:44 PM] Designing DLSw+ InternetworksTable of ContentsDesigning DLSw+ InternetworksIntroduction to DLSw+DLSw+ DefinedDLSw StandardEstablish Peer ConnectionsExchange CapabilitiesEstablish CircuitFlow ControlDLSw+ FeaturesDLSw+ Improved ScalabilityPeer Group ConceptExplorer FirewallsDLSw+ Enhanced AvailabilityDLSw+ Transport FlexibilityDLSw+ Modes of OperationHow to ProceedGetting Started with DLSw+Minimum Required ConfigurationToken RingEthernetSDLCQLLCDLSw+ Advanced FeaturesHow DLSw+ Peers Establish ConnectionsLoad Balancing and RedundancyControlling Peer SelectionBackup PeersBackup Peers Compared to Multiple Active PeersEncapsulation OptionsTCP EncapsulationFST EncapsulationDirect EncapsulationLLC2 Encapsulation (DLSw Lite)Encapsulation OverheadPort ListsPeer Groups, Border Peers, and On-Demand Peershttp://www.cisco.com/cpress/cc/td/cpress/ccie/ndcs798/nd2007.htm (1 of 26) [9/16/2000 5:07:19 PM] Designing DLSw+ InternetworksDynamic PeersWhen to Use Dynamic PeersSNA Dial-on-Demand RoutingOther ConsiderationsLocal SwitchingSummaryDesigning DLSw+ InternetworksThis chapter contains the following information:Introduction to DLSw+Getting Started with DLSw+DLSw+ Advanced FeaturesIntroduction to DLSw+This section describes Data Link Switching Plus (DLSw+) and provides configuration examples to enable you toquickly design and configure simple DLSw+ networks.It reviews the key components of the data-link switching(DLSw+) features and describes the extensions to the standard that are included in DLSw+.This section alsodescribes advanced features, tells when to use them, and includes examples of how to use these features.It providestuning, hierarchical design, meshed design, debug, and migration guidance.Finally, it recommends how to proceedwith designing your network.This section can be used as a reference only (for configuration examples), as a tuningguide, or as a guide to design a complete DLSw+ network.DLSw+ DefinedDLSw+ is a means of transporting Systems Network Architecture (SNA) and NetBIOS traffic over a campus orwide-area network (WAN).The end systems can attach to the network over Token Ring, Ethernet, Synchronous DataLink Control (SDLC) protocol, Qualified Logical Link Control (QLLC), or Fiber Distributed Data Interface (FDDI).(FDDI is supported on the Cisco 7000 series only and requires Cisco IOS Release11.2 or later.) DLSw+ switchesbetween diverse media and locally terminates the data links, keeping acknowledgments, keepalives, and polling offthe WAN.Local termination of data links also eliminates data-link control timeouts that can occur during transientnetwork congestion or when rerouting around failed links.Finally, DLSw+ provides a mechanism for dynamicallysearching a network for SNA or NetBIOS resources and includes caching algorithms that minimize broadcast traffic.In this document, DLSw+ routers are referred to as peer routers, peers, or partners.The connection between twoDLSw+ routers is referred to as a peer connection.A DLSw+ circuit compromises the data-link control connectionbetween the originating end system and the originating router, the connection between the two routers (typically aTransport Control Protocol [TCP] connection), and the data-link control connection between the target router and thetarget end system.A single peer connection can carry multiple circuits.DLSw+ supports circuits between SNA physical units (PUs) or between NetBIOS clients and servers.The SNA PUconnectivity supported is PU 2.0/2.1-to-PU 4 (attached via any supported data-link controls), PU 1-to-PU 4 (SDLConly), PU 4-to-PU 4 (Token Ring only), and PU 2.1-to- PU 2.1 (any supported data-link control).See "IBM SerialLink Implementation Notes," for details about DLSw+ connectivity.Note N PU 4-to-PU 4 connectivity supports only a single path between front-end processors (FEPs) because of anidiosyncrasy in how FEPs treat duplicate source-route bridged paths [ Pobierz caÅ‚ość w formacie PDF ]