3com S7906E 설치 설명서

 

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An MPLS LSR ID is in the format of an IP address and must be unique within an MPLS domain. 
You are recommended to use the IP address of a loopback interface on an LSR as the MPLS LSR 
ID. 

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At present, the S7900E series switches support enabling MPLS on only VLAN interfaces. 

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As MPLS will encapsulate original packets with single layer or multiple layers of labels, after 
enabling MPLS on the VLAN interface of a VLAN, you are recommended to enable the jumboframe 
function on the ports of the VLAN and configure a proper jumbo frame length to prevent packets 
from being dropped due to size limit. For example, if two layers of MPLS labels are required for 
encapsulating FTP packets, you need to configure the jumbo frame length on related ports to 1544 
bytes: 1518 bytes for the FTP packet + 4 bytes × 2 for the MPLS labels + 4 bytes for the VLAN tag 
+ 14 bytes for the Ethernet frame header. For descriptions of the jumboframe function, refer to 

 in the Access Volume. 

 

Configure PHP on an egress and select the type of labels for the egress to distribute based on whether 
the penultimate hop supports PHP. 

Before configuring PHP, be sure to complete the following task: 

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Configuring MPLS basic capability on all LSRs. 

According to RFC 3032 “MPLS Label Stack Encoding”: 

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A label value of 0 represents an IPv4 explicit null label and is valid only when it appears at the 
bottom of a label stack. 

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A label value of 3 represents an implicit null label and never appears in the label stack. When an 
LSR finds that it is assigned an implicit null label, it directly performs a pop operation, rather than 
substitutes the implicit null label for the original label at the stack top. 

Follow these steps to configure PHP: 

Enter system view 

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Enter MPLS view 

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