Alcatel-Lucent 7705 - MTU Settings; Figure 34: MTU Points on the 7705 SAR

VLL Service Considerations
Page 186 7705 SAR OS Services Guide
MTU Settings
There are several MTU values that must be set properly for a VLL service (Apipe, Cpipe,
Epipe, or Ipipe) to work from end to end. Figure 34 locates the MTU point for each value.
Table 28 describes the MTU points. The MTU points are:
• access port MTU
•SAP MTU
•service MTU
•path MTU
• network port MTU
In order for a VLL service to be declared “up” without any MTU-related error messages, the
following rule must be true:
SAP MTU ≥ Service MTU ≤ Path MTU
Figure 34: MTU Points on the 7705 SAR
19688
NP
SAP
NP
SDP
Access Port MTU
SAP MTU
Service MTU
3
Network Port MTU
5
Path MTU
4
1
2
Ingress Line
Card
Network Egress
Line Card
Fabric
Access Network