Lucent Optical Management System (oms) Release
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- Điều hướng trang này:
- Final destination
- Alcatel-Lucent - Proprietary
| Final destination
Next hop Subnetwork Node 130.44.5.0/24 LAN 0 120.23.4.0 / 24 LAN 0 130.44.5.8 150.35.10.0 / 24 DCC 1 - 150.35.20.0 / 24 DCC 2 - 160.22.0.0 / 16 CLNP-Tunnel NSAP (node X) Final destination This column of the routing table is a list of all the final destination nodes. When a packet is received at this node, then the destination address in that packet is checked against the list of destinations in the destination column of the routing table. If there is no entry in the table for the packet destination, then the node won’t know how to route Management communication setup concepts Dual stack with tunneling (DSwT) ................................................................................................................................................................................................................................... 3-16 Alcatel-Lucent - Proprietary See notice on first page 365-312-875R5.2 Issue 1, March 2007 the packet and will execute the error procedure (which involves discarding the packet and trying to send an error message packet back to the source). If a match is found, the next hop towards the destination can be looked up in he “Next hop” column. IP prefixes An IP prefix is a mechanism of identifying a collection of IP addresses with some common root. The general principle is to choose a mask which identifies a suitable first part of the IP address which summarizes a number of addresses. For example, the addresses 120.10.2.1, 120.10.2.5 and 120.10.2.13 can be summarized by the IP prefix: 120.10.2.0 / 24. The 24 identifies the first 24 bits of the address. Summarizing IP addresses is a very powerful way to reduce the number of entries in a routing table. Next hop Two pieces of information are needed in order to identify the next hop node: • On which subnetwork (for example on which exit port) is the next hop node, • Which node on that subnetwork is the next hop To send a packet to the destination “Dest”, the source must identify the node next hop. This is identified by the subnetwork (on port 2 of source) and then the node on that subnetwork (identified by B). In OSI terminology the address B is known as a subnetwork point of attachment (SNPA), which is the point that the node is attached to the subnetwork. The second column in the routing table is the next hop and is divided into 2 parts: • The next hop subnetwork • The next hop node tải về 2.06 Mb. Chia sẻ với bạn bè của bạn:
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