Receive Processing; Mlp Bundle Interface And Service Policies; Transmit Processing - Cisco 10000 Series Configuration Manual

Multilink PPP-Based Link Fragmentation and Interleaving

MLP Bundle Interface and Service Policies

The router applies a service policy, attached to a multilink interface, to only the MLP bundle interface.
The QoS actions defined by the service policy are applied to the outbound nonreal-time packets before
the packets reach the bundle first-in first-out (FIFO) queue. The nonreal-time packets are fragmented in
the FIFO queue and then the real-time packets are interleaved between the fragments as the real-time
packets exit their priority queue.

Transmit Processing

The purpose of MLP over Frame Relay-based LFI transmit processing is to fragment large nonreal-time
delay-insensitive packets and interleave smaller real-time delay-sensitive packets between the
fragments. Each MLP bundle has multiple transmit packet queues. MLP does not interleave packet
fragments from different packet queues associated with a given MLP bundle. Instead, MLP transmits all
of the fragments associated with a nonreal-time packet in order before transmitting fragments from
another nonreal-time packet. MLP posts all of the packets from the various nonreal-time packet queues
to a single bundle first-in first-out (FIFO) queue.
It is from this single bundle queue that MLP does the following:
•
•
•
Real-time traffic, such as voice, are queued intact to a priority (low-latency) queue. It is from this queue
that MLP transmits the real-time packets and interleaves them between the nonreal-time fragments.
Because real-time packets are not MLP encapsulated or fragmented, MLP can safely interleave these
packets as needed. Traffic transmitted from the priority queue takes precedence over the MLP
encapsulated traffic that is transmitted from the related bundle queue.
Figure 16-4
Figure 16-5
Delay Insensitive
Packet Queues
Delay Sensitive
Packet Queues

Receive Processing

The purpose of MLP over Frame Relay-based LFI receive processing is to reassemble MLP over Frame
Relay encapsulated packet fragments into PPP over ATM packets. During receive processing, the
fragments that arrive out of order and the packets with missing fragments are discarded. Valid fragments
are merged in memory until the entire packet is reassembled.
Cisco 10000 Series Router Quality of Service Configuration Guide
16-22
Fragments nonreal-time traffic
Encapsulates the fragments with MLP
Transmits the fragments
shows an example of the packet flow of real-time and nonreal-time packets.
MLP Over Frame Relay-Based LFI Packet Queue Flow
Bundle FIFO
Chapter 16 Fragmenting and Interleaving Real-Time and Nonreal-Time Packets
Queue
Link
OL-7433-09