User`s guide

Chapter 11 SIP Account Setup
V500 Series User’s Guide
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Tone. Each of the keys on a DTMF telephone corresponds to a different pair of
frequencies.
Pulse dialing sends a series of clicks to the local phone office in order to dial
numbers.
MWI (Message Waiting Indication)
Enable Message Waiting Indication (MWI) enables your phone to give you a
message–waiting (beeping) dial tone when you have one or more voice messages.
Your VoIP service provider must have a messaging system that sends message-
waiting-status SIP packets as defined in RFC 3842.
Quality of Service (QoS)
Quality of Service (QoS) refers to both a network's ability to deliver data with
minimum delay and the networking methods used to provide bandwidth for real-
time multimedia applications.
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 V500) so a server can decide the best method of
delivery, that is the least cost, fastest route and so on.
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.
DSCP and Per-Hop Behavior
DiffServ defines a new DS (Differentiated Services) field to replace the Type of
Service (TOS) field in the IP header. The DS field contains a 2-bit unused field and