Method and apparatus for forwarding label

Abstract

The invention provides a label retransmission method and a device thereof. The method comprises the following steps: a first layer of label is received as a message of a first label; a following data unit adjacent to the first label is taken as a label or an IP message; and the first label is popped up and message following the first label popped up is transmitted to a loopback port. The method is used for meeting the requirement of processing message of a plurality of labels and a single label at the same time when an exchanger cannot support PHP.

Description

technical field [0001] The invention relates to a label forwarding method and device, belonging to the technical field of data communication. Background technique [0002] MultiProtocol Label Switching (MPLS for short) is a system for fast data packet switching and routing, which provides capabilities such as destination, routing, forwarding and switching for network data traffic. MPLS supports a variety of network layer protocols, such as Internet Protocol (IP for short), Internet Protocol version 6 (IPv6 for short), Internet Packet Exchange protocol (IPX for short), and is compatible with Asynchronous Transfer Mode (ATM for short), Frame Relay, Ethernet, Point to Point Protocol (PPP for short) and other link layer technologies; the so-called label switching is to attach Label, forward according to the label. [0003] The label forwarding table (Incoming Label Map, ILM for short) is used to map each incoming label to a series of next-hop forwarding entities (generally, sw...

AI Technical Summary

Problems solved by technology

[0032] If the requirements of scenario 1 are met, the requirements of scenario 2 cannot be met, because the packet in scenario 2 carries only one public network label. After matching the label forwarding table in scenario 1 according to the public network label, the found behavior is to pop up the label and then search for the label. Forwarding table, after the public network label is popped up, there is no label in the packet, and if you look for the label forwarding table, the packet will be discarded because there is no matching label

[0033] If the requirements of scenario 2 are met, the requirements of scenario 1 cannot be met, because the packet in scenario 1 carries two labels, public network and private network. After matching the label forwarding table in scenario 2 according to the public network label, the queried behavior is to pop up the label Then query the routing table, after popping up the public network label, because the packet still carries the private label, when querying the routing table according to the set behavior, because the packet is still an MPLS packet instead of an IP packet, it cannot be configured according to the destination IP address. Query the correct route and discard the message

[0034] If you want to prevent the above problems, you need to make restrictions when deploying the network: such as figure 1 The two PE devices in the network cannot be used as the egress devices of the Layer 3 VPN network and the ordinary MPLS network at the same time, but this will undoubtedly increase the device resources and increase the difficulty of network deployment.

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