Enterasys Matrix 7G4270-12, Руководство по настройке

Страница: 23 / 29

QoS Configuration Example
February 22, 2008 Page 23 of 29
QoS Configuration Example
In our example, an organization’s network administrator needs to assure that VoIP traffic, both
originating in and transiting the network of N ‐ Series edge switches and a DFE core router, is
configured for QoS with appropriate priority, ToS, and queue treatment. We will also rate limit the
VoIP traffic to at the edge to 1024 Kbps to guard against DOS attacks, VoIP traffic into the core at
25 Mbps, and H.323 call setup at 5 pps. Data traffic retains the default configuration.
This example places QoS configuration within a policy context. Policy is not required to configure
QoS.
This example assumes CEP authentication using H.323 for VoIP. If you are not authenticating your
VoIP end point with CEP H.323 authentication, you will need to adjust the VoIP policy
accordingly. For instance, SIP uses UDP port 5060, not the TCP port 1720.
For purposes of avoiding complexity that would get in the way of understanding the
configuration process, this example limits the discussion to the VoIP configuration context. Table 1
provides a set of sample values for priority, IRL, and transmit queue across a number of real world
traffic types. This table can be used as an aid in thinking about how you might want to apply CoS
across your network. Note that scavenger class is traffic that should be treated as less than best
effort: external web traffic, for instance.
Figure 7 displays the network setup for this example configuration, with the desired Profile/QoS
summary for each network node. Each node is configured with VoIP and Data VLANs. Each VoIP
VLAN contains four 1 ‐ gigabit interfaces for each node.
Notes: Enterasys highly recommends that you use the NetSight Policy Manager to
configure QoS on your network, whether you are applying policy or not. This example
discusses the QoS configuration using Policy Manager followed by CLI input summaries.
Table 1 CoS Sample Values By Traffic Type
Name Priority
IRL
Transmit Queue
Queue # Shaping WFQ
Edge Core Edge Core Edge Core Edge Core
Loop Detect 0 10 PPS 10 PPS
0 0 10% 5% 5%
Scavenger 0 15 Mbps
Best Effort 1
1 1 80% 45% 45% Bulk Data 2
Critical Data 3
Network Control 4 40 PPS 1 Mbps
2 2 1Mbps 25% 25%
Network
Management
5 2 Mbps
RTP 6
1 Mbps 25 Mbps 3 3 25% 25%
Voice/Video 7