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Cisco 10000 Series Router Software Configuration Guide
OL-2226-23
Chapter 22 Configuring Multilink Point-to-Point Protocol Connections
Single-VC MLP over ATM Virtual Circuits
•
You cannot apply a virtual template with MLP configured to an MLP bundle.
•
We strongly recommend that you use only strict priority queues when configuring MLP over
Serial-based LFI. For more information, see the “Prioritizing Services” chapter in the
Cisco 10000
Series Router Quality of Service Configuration Guide
.
Single-VC MLP over ATM Virtual Circuits
The Single-VC MLP over ATM virtual circuits (VCs) feature enhances the MLP over Serial interfaces
feature by enabling you to configure multilink Point-to-Point Protocol (MLP) on an ATM VC. By doing
so, you can aggregate multiple data paths (for example, PPP over ATM encapsulated ATM VCs) into a
single logical connection called an MLP bundle (see the
“MLP Bundles” section on page 22-3
). The
MLP bundle can have only one member link.
MLP supports link fragmentation and interleaving (LFI). When enabled, the MLP fragmentation
mechanism multilink encapsulates large nonreal-time packets and fragments them into a small enough
size to satisfy the delay requirements of real-time traffic. The smaller real-time packets remain intact and
MLP sends the packets to a special transmit queue, allowing the packets to be sent earlier than other
packet flows. The MLP interleaving mechanism sends the real-time packets between the fragments of
the nonreal-time packets. For more information about link fragmentation and interleaving, see the
“Fragmenting and Interleaving Real-Time and Nonreal-Time Packets” chapter in the
Cisco 10000 Series
Router Quality of Service Configuration Guide
.
Performance and Scalability for Single-VC MLP over ATM
•
Configure the
hold-queue
command in interface configuration mode for all physical interfaces,
except when configuring the OC-12 ATM line card. The 1-Port OC-12 ATM line card does not
require the
hold-queue
command. For example:
Router(config-if)#
hold-queue 4096
in
•
Configure the following commands and recommended values on the virtual template interface:
–
ppp max-configure
110
–
ppp max-failure
100
–
ppp timeout retry
5
–
keepalive
30
For example:
Router(config-if)#
ppp max-configure
110
Router(config-if)#
ppp max-failure
100
Router(config-if)#
ppp timeout retry
5
Router(config-if)#
keepalive
30
For more information, see the “Scalability and Performance” chapter in this guide.
Restrictions and Limitations for Single-VC MLP over ATM
•
Only one member link is supported per bundle.
•
Single-VC MLP over ATM member links are restricted to nonaggregated PVCs (for example,
variable bit rate-nonreal-time [VBR-nrt] and constant bit rate [CBR] ATM traffic classes only).
