3Com OfficeConnect 3CRWDR200A-75, User Manual

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C
HAPTER
4: R
UNNING THE
S
ETUP
W
IZARD
communications applications. The UBR service may be considered as
"best effort service". Peak cell rate specifies the maximum cell rate at
which the user will transmit.
CBR (constant bit rate): the CBR service class is intended for
real-time applications, for example, those requiring tightly constrained
delay and delay variation, such as voice and video applications. The
consistent availability of a fixed quantity of bandwidth is considered
appropriate for CBR service.
VBR (Variable Bit Rate) is subdivided into a real time (RT) class and
non-real time (NRT) class. VBR (RT) is used for connections in which
there is a fixed timing relationship between samples. VBR (NRT) is
used for connections in which there is no fixed timing relationship
between samples, but that still need a guaranteed QoS. Typical VBR
sources are compressed voice and video. These applications require
small delay variations.
Figure 16
The ATM Configuration screen
IGMP
IGMP stands for Internet Group Management Protocol which is defined
in RFC 1112 as the standard for IP Multicast.
Select to enable IGMP multicast.
Select to enable WAN service and enter the service name to identify
your internet service.
Connection Mode
Select an Internet Addressing mode from the following: