Before You Begin - ZyXEL Communications MAX208M User Manual

Chapter 9 The VoIP General Screens
Type Of Service (ToS)
Network traffic can be classified by setting the ToS (Type Of Service) values at the data source (for
example, at the WiMAX Device) so a server can decide the best method of delivery, that is the least
cost, fastest route and so on. The ToS field is consist of 8 bits. The first 3 bits indicate the priority of
the packet.
DiffServ
DiffServ is a class of service (CoS) model that marks packets so that they receive specific per-hop
treatment at DiffServ-compliant network devices along the route based on the application types
and traffic flow. Packets are marked with DiffServ Code Points (DSCPs) indicating the level of
service desired. This allows the intermediary DiffServ-compliant network devices to handle the
packets differently depending on the code points without the need to negotiate paths or remember
state information for every flow. In addition, applications do not have to request a particular service
or give advanced notice of where the traffic is going.
DiffServ uses the first 6 bits of the 8-bit ToS value so that it can be backward compatible with non-
DiffServ compliant but ToS-enabled network device. See
information.
SIP
The Session Initiation Protocol (SIP) is an application-layer control (signaling) protocol that handles
the setting up, altering and tearing down of voice and multimedia sessions over the Internet. SIP
signaling is separate from the media for which it handles sessions. The media that is exchanged
during the session can use a different path from that of the signaling. SIP handles telephone calls
and can interface with traditional circuit-switched telephone networks.
RTP
When you make a VoIP call using SIP, the RTP (Real time Transport Protocol) is used to handle voice
data transfer. See RFC 1889 for details on RTP.
Speed Dial
Speed dial provides shortcuts for dialing frequently used phone numbers. You can map a phone
number to a self-defined key(s) and then use that key(s) to call the phone number. For example,
you can map 123456 to #01. When you press #01 it means that you press 123456.

9.1.2 Before you Begin

• Ensure that you have all of your voice account information on hand. If not, contact your voice
account service provider to find out which settings in this chapter you should configure in order
to use your telephone with the WiMAX Device.
• Connect your WiMAX Device to the Internet, as described in the Quick Start Guide. If you have
not already done so, then you will not be able to test your VoIP settings.
152
Section 9.6.1 on page 156
WiMAX Device Configuration User's Guide
for more