Cisco 10000 Series

16-21
Cisco 10000 Series Router Quality of Service Configuration Guide
OL-7433-09
Chapter 16 Fragmenting and Interleaving Real-Time and Nonreal-Time Packets
Multilink PPP-Based Link Fragmentation and Interleaving
Line Card Support for MLP Over ATM-Based LFI
The following line cards support MLP over ATM-based LFI for the Cisco 10000 series router:
• 8-Port E3/DS3 ATM
• 4-Port OC-3/STM-1 ATM
• 1-Port OC-12 ATM
MLP Over Frame Relay-Based LFI
MLP over Frame Relay-based LFI uses the fragmentation and interleaving capability of MLP to
transport real-time traffic (for example, voice) and nonreal-time traffic (for example, data transfers)
together on low-speed Frame Relay permanent virtual circuits (PVCs) without causing excessive delay
to the real-time traffic. MLP over Frame Relay-based LFI supports RFC 1990, The PPP Multilink
Protocol.
MLP over Frame Relay-based LFI makes it possible for delay-sensitive packets and delay-insensitive
packets to share the same link by fragmenting the long data packets into a sequence of smaller data
packets referred to as fragments. The fragments are interleaved with the real-time packets. On the
receiving side of the link, the fragments are reassembled and the packet is reconstructed. This method
of fragmenting and interleaving helps guarantee the appropriate QoS for the real-time traffic.
When configuring MLP over Frame Relay-based LFI, you must configure a virtual template interface
for the MLP bundle. The virtual template must be unique to only that bundle—multiple MLP bundles
cannot share the same virtual template.
For more information about MLP, see the “Multilink PPP-Based Link Fragmentation and Interleaving”
section on page 16-11 and the Cisco 10000 Series Router Broadband Aggregation, Leased-Line, and
MPLS Configuration Guide.
Feature History for MLP Over Frame Relay-Based LFI
Multilink Group Interfaces and Virtual Template Interfaces
You can configure MLP by assigning a multilink group to a virtual template interface configuration.
Virtual templates allow a virtual access interface (VAI) to dynamically clone interface parameters from
the specified virtual template. If you assign a multilink group to a virtual template and you assign the
virtual template to a physical interface, all of the links that pass through the physical interface belong to
the same multilink bundle.
Cisco IOS Release Description Required PRE
Release 12.2(27)SBB The MLP over Frame Relay-based LFI feature was
introduced on the router for the PRE2.
PRE2
Release 12.2(31)SB2 This feature was introduced on the PRE3. PRE3