Alcatel-Lucent 7750 Configuration Manual page 171

Table 28: MTU Configuration Example Values (Continued)
Port (slot/MDA/port)
Mode type
MTU
Since ALA-A uses Dot1q encapsulation, the SAP MTU must be set to 1518 to be able to accept a
1514 byte service frame (see
least 1514 as well. If ALA-A's network port (2/1/1) is configured as an Ethernet port with a GRE
SDP encapsulation type, then the MTU value of network ports 2/1/1 and 3/1/1 must each be at
least 1556 bytes (1514 MTU + 28 GRE/Martini + 14 Ethernet). Finally, the MTU of ALA-B's
SAP (access port 4/1/1) must be at least 1514, as it uses null encapsulation.
7750 SR Interface Configuration Guide
1/1/1 2/1/1
dot1q network
1518 1556
Table 27 for MTU default values). Each SDP MTU must be set to at
Interface Configuration
3/1/1 4/1/1
network null
1556 1514
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