Enterprise QoS Solution Reference Network Design Guide

Teleworker V3PN QoS Designs
6-40
Enterprise QoS Solution Reference Network Design Guide
Chapter 6 IPSec VPN QoS Design
pppoe-client dial-pool-number 1
!
...
!
interface Dialer1
description Dialer for PPPoE
ip address negotiated
ip mtu 1492
encapsulation ppp
ip tcp adjust-mss 542 ! TCP MSS value tuned for slow-link
!
...
!
ip access-list extended IKE
permit udp any eq isakmp any eq isakmp ! ISAKMP ACL
!
Verification commands:
show policy
show policy interface
show atm pvc
Integrated Unit + Access Model—DSL/Cable Designs
Hierarchical MQC policies are required for Integrated Unit + Access Models to shape and queue (within
the shaped rate) on the outbound Ethernet interface. For cable, the shaped rate should be 95 percent of
the broadband link’s speed (as detailed in Chapter 3, “WAN Aggregator QoS Design” in the “Frame
Relay” section [“Committed Information Rate” subsection]). For DSL, the shaped rate should be 70
percent of the uplink’s speed (to account for the increased bandwidth overhead required by DSL).
Furthermore, on slow-speed (£ 768 kbps) links, TCP-MSS should be tuned on both the inbound and
outbound Ethernet interfaces. An Integrated Unit + Access Model for a 384-kbps cable teleworker uplink
is shown in Figure 6-29 and detailed in Example 6-10.
Figure 6-29 Integrated Unit + Access V3PN Teleworker Model for 384-kbps Cable Uplink
384 kbps
Cable Uplink Rate
Shaped to 95%
of Uplink Rate
Best-Effort
60%
Voice - 128 kbps
35%
Call-Signaling 5%
Internetwork Control 5%
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