Technical data

242 Meru System Director Configuration Guide © 2012 Meru Networks, Inc.
Optimizing Voice Over IP
In practice, this means that if your VoIP devices are configured correctly, that is, if
they know how to find their SIP or H.323v1 server and the servers understand how to
find them, then the VoIP devices should work when communicating over the Meru
Meru Wireless LAN System without any special configuration.
Using Meru Wireless LAN System QoS Rules for VoIP
As discussed in the previous section, quality voice traffic has different network
requirements than does typical network traffic. The Meru Wireless LAN System is
designed to automatically provision voice traffic with a level of QoS appropriate for
voice calls. The result is that VoIP traffic works much better over a Meru Meru Wire-
less LAN System than it does over most WLANs.
The controller watches the traffic passing through it and when it sees packets from
stations to servers on ports reserved for SIP or H.323v1 service, it tracks subsequent
communication in that sequence and provisions the VoIP call with a level of service
appropriate for a VoIP call.
The port numbers watched are:
 5060 for SIP service (UDP or TCP)
 1720 for H.323v1 service (TCP)
 5200 for Vocera (UDP)
These are the standard port numbers for these services. If your VoIP devices use
these ports to communicate with their servers, you do not need to configure VoIP QoS
rules on your system.
If your VoIP devices and servers are configured to use different ports, you will need
to modify the QoS rules on the controller to match the ports your system uses.
Change QoS rules with either the Web UI or the CLI.
Modifying QoS Rules for Nonstandard Ports
The controller is pre-configured to detect the bandwidth requirements for a SIP or
H.323v1 call and make a bandwidth reservation. Change QoS rules with either the
Web UI or the CLI. The following default QoS rules are configured at the factory:
default(15)# show qosrule
ID Dst IP Dst Mask DPort Src IP Src Mask SPort Prot
Firewall Filter Qos Action Drop
1 0.0.0.0 0.0.0.0 1720 0.0.0.0 0.0.0.0 0 6
h323 capture head
2 0.0.0.0 0.0.0.0 0 0.0.0.0 0.0.0.0 1720 6
h323 capture head
3 0.0.0.0 0.0.0.0 5060 0.0.0.0 0.0.0.0 0 17
sip capture head
5 0.0.0.0 0.0.0.0 5060 0.0.0.0 0.0.0.0 0 6
sip capture head