22-25
Cisco 10000 Series Router Software Configuration Guide
OL-2226-23
Chapter 22 Configuring Multilink Point-to-Point Protocol Connections
MLPoE at PTA
•
QoS on interfaces towards the CPE and the tunnel is not supported.
•
Only single-member MLPoE bundles are supported (with LFI support). The maximum number of
single-member MLPoE bundles that can be supported is 10240.
MLPoE at PTA
In Cisco IOS Release 12.2(33)SB, MLPoE supports LFI on single-link MLP bundles. This support
enables high priority and low-latency packets to be interleaved between fragments of lower-priority and
higher-latency packets.
Figure 22-6
shows a MLPoE DSL network using LFI.
Figure 22-6
MLPoE DSL Network with LFI
In the upstream direction, the CPE fragments non-priority packets and interleaves high priority packets
between the fragments. In the downstream direction, the Cisco 10000 series router reassembles the
fragmented non-priority packets. However, from Cisco IOS Release 12.2(33)XNE onwards, to reduce
any delay in sending high-priority packets, the router processes high priority packets as soon as they
arrive.
Point-to-Point Protocol over Ethernet (PPPoE) sessions in the MLPoE at PTA feature are handled as
follows:
•
All variations of PPPoE, such as PPPoEoE, PPPoEoA, PPPoEo802.1Q, and PPPoEoQinQ, are
usable as member links for MLPoE bundles.
•
Termination of a MLPoE bundle in a Virtual Routing and Forwarding (VRF) block is similar to
terminating a PPPoE session in a VRF.
•
MLPoE bundles are distinguished by the username that was used to authenticate the PPPoE session.
•
MLPoE reassembles received fragmented MLP packets, but fragmentation is not performed in the
transmit direction.
•
PPPoE sessions are dynamically created and cannot be pre-configured similar to MLPoA for
bundling with a multilink interface. MLPoE bundles are also dynamically created when a PPPoE
session, with the multilink option enabled, is configured for a user for the first time.
CPE
C10000
BRAS
277390
I
nterleaved
MPLoE
I
nterleaved
MPLoE
DSLAM
Vo
I
P
Data
Vo
I
P
Data
Ethernet
Backhaul