FAQ Maxwell - Network - LAN

A local network can be divided into logical sub-networks, so-called VLANs (Virtual Local
Area Network, standard IEEE 802.1Q). Multiple VLANs share a physical network and its
components, e.g., switches. Data packets of a VLAN are not forwarded to another VLAN.
VLANs are often used to separate the data traffic of different services (Internet telephony,
Internet TV, ...) and to define different priorities for the data traffic.
If you are operating your phone in a VLAN, enter the identifier of your VLAN (VLAN tag)
here. You get this from your network administrator.

Data packets from VLANs can be prioritised. The priority determines whether the data
traffic from a VLAN is given preferential treatment by the network components. You can
define the priority for voice and data separately. In the case of a local network with a lot
of data traffic, you can achieve better-quality phone connections by giving a high priority
to voice data.

On the menus Voice VLAN Priority and Data VLAN Priority, select the priorities you
want for the transfer of voice and data.
Range of values and their Class of Service assignments (according to IEEE 802.1p):

0 No priority (Best Effort)
1 Background services, e.g., News Ticker (Background)
2 Not defined
3 General data services (Excellent Effort)
4 Control services, e.g., routing (Controlled Load)
5 Video
6 Voice data (Voice)
7 Top priority for network control software (Network Control)

The voice quality depends on the priority of the voice data in the IP network. Prioritising
the VoIP data packets is done using the QoS protocol DiffServ (Differentiated Services).
DiffServ defines a number of classes for the quality of service and, within these classes,
various priority levels for which specific prioritisation procedures are defined.
You can specify different QoS values for SIP and RTP packets. SIP packets (Session Initiation
Protocol) contain the signalling data, while RTP (Real-time Transport Protocol) is used
for the voice transfer.

Enter your chosen QoS values in the SIP ToS/Diffserv (0..63) and RTP ToS/Diffserv
(0..63) fields. Value range: 0 - 63.
Common values for VoIP (default setting):

• SIP 40 Highest service class for fast switching of the data flow (Expedited Flow)
• RTP 46 Highest service class for fast forwarding of data packets (Expedited Forwarding)