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Abstract In recent years research in full swing on the conduct of ASON, ASON for the next generation optical transport network, providing high capacity bandwidth, and because the introduction of control plane to have a high intelligence, the bandwidth can be achieved by be automatically assigned, optical VPN services. At the same time, real-time streaming technology on the network business is rapidly rising. How to combine the two organic has become the industry has a research focus, ASON signaling P2MP research is an important aspect. 1 Introduction ASON (Automatically Switched Optical Network) is a signaling network can intelligently under the control automatically switched optical network connectivity and configuration capabilities of next-generation optical transport network. The intelligence comes from its ASON control plane (CP), with a separate control plane is its transmission network with the traditional important difference, it can be said ASON control plane technology is a dynamic and intelligent key. ASON its optical switching characteristics and good survival of delay and packet loss can reduce the impact of quality of service (QoS). At the same time, in recent years based on multipoint (P2MP) video conference, live broadcast, VoD, IPTV, live real-time services such as streaming media has been growing rapidly. They require a high QoS guarantee (including the packet loss rate, delay jitter, bandwidth etc.). ASON network characteristics very consistent with these requirements, it takes to be a good streaming media service bearer network platform. 2, ASON control plane key technologies MPLS (Multi Protocol Label Switching) is essentially a special kind of packet classification forwarding technology, introduced in the MPLS forwarding equivalence class (FEC) and labels (Label) concept. MPLS network from the core part of the label switching routers (LSR) and the edge of the label edge router (LER) composition, which is responsible for tagging the data packets and to label operations. The old label is a new label routing table substitute, packets are forwarded to the next hop, the label is removed export LER Department, again using the IP routing mechanism. From the source and purpose of LSR LSR LSR series between the link between them constitute the path known as Label Switched Path (LSP). GMPLS (Generalized Multi-protocol Label Switching) as a key technology ASON control plane is based on the MPLS applicable to the expansion of optical networks, it can provide the complete separation of routing and signaling. The label on the MPLS GMPLS was extended to TDM time slot, optical wavelength and fiber were also marked with a unified label. MPLS network to use more resource reservation protocol with traffic engineering extensions (RSVP-TE) signaling protocol, as one can achieve good traffic engineering (TE), to support restrictions on routing (including Call Admission Control CAC and explicit routing LSP ER-LSP establishment), can provide efficient use of resources, rapid recovery and strict QoS guarantees. GMPLSRSVP-TE in MPLSRSVP-TE based on the extension accordingly, to meet the optical network point to point (P2P) connections create, delete and modify functions. 3, ASON multicast signaling Existing ASON control plane technology, the basic research are based on P2P, and can be used to achieve point to point label switched path ASON multicast, as long as the label switching router Department at the entrance to a simple packet replication can be achieved. But this would introduce a problem: the network are filled with a large number of useless duplicate packets, wasting network bandwidth and reduce network load. Must therefore introduce a new mechanism or on the existing GMPLSRSVP-TE signaling protocol multicast extensions. Generally prefer the latter, because although IP network can be introduced in order to achieve the ASON IGMP multicast, but since IP and ASON are two completely different networks, this workload will be immense; and if the existing P2P agreement P2MP extensions to the various branches of ASON network nodes can be effectively replicated packets can effectively save network resources. The so-called branch nodes can access the data is copied to two or more out interface, and different interfaces can be used different labels. ASON control plane based on the GMPLSP2MP extend RSVP-TE and conversation related to business signs, explicit routing, grafting and pruning and RSVP message processing, and several other key issues to be discussed. 3.1 Identification of business and conversation Label switching tunnel (LSPTunnel) formed by one or more P2MPLSP can introduce multipoint session object (P2MPSES-SION) to mark. P2MPSESSION object is P2PRSVP-TE extensions in the SESSION object obtained by the combination <P2MPID,TunnelID,ExtendedTunnelID> logo, which identifies a business TunnelID tunnel, P2MPID identify the business, a collection of multiple client connections, and RSVP- TE in the SESSION object is different in its tunnel end point address (TunnelEndpointAddress) field is P2MPSESSION object P2MPID field instead. P2MPLSP is a more than one entrance and exit LSR LSR of the LSP, this path is one-way. Identified by <P2MPID,TunnelID,ExtendedTunnelID,TunnelSenderAddress,LSPID> combination, which TunnelSenderAddress the sender address on behalf of business, P2MPLSP included in the multipoint sender template (P2MPSENDER_TEMPLATE) object. A P2MPLSP another by a number of sub-label switched path (sub-LSP) component, which is the import and export of LSR LSR connection between. A sub-LSP is identified by <P2MPID,TunnelID,ExtendedTunnelID,TunnelSenderAddress,LSPID,sub-LSPdestinationaddress> portfolio, including sub-LSPdestinationaddress (sub label switched path destination address) in the S2L_SUB_LSP object. In P2PRSVP-TE LSP through the state of RSVP messages on the management and maintenance, as can the status of RSVP messages on P2MPLSP maintained, however, there is a difference between the two, as in a P2MPLSP contains many sub- LSP, so if an RSVP message with the status of the maintenance of a P2MPLSP may not result in the message length is difficult to express all the sub-LSP state problem, this time should be supported by multiple RSVP messages; In addition, because a P2MPLSP with multiple destination node, sometimes the situation appears grafting and pruning The e-commerce company in China offers quality products such as Self Adhesive Sticker Manufacturer , China Recycled Paper Notebook, and more. For more , please visit Spiral Bound Notepad today!
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