ZyXEL Communications P-793H Benutzerhandbuch

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 Chapter 5 WAN Setup
P-793H User’s Guide
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5.3.1  ATM Traffic Classes
These are the basic ATM traffic classes defined by the ATM Forum Traffic Management 4.0 
Specification. 
5.3.1.1  Constant Bit Rate (CBR)
Constant Bit Rate (CBR) provides fixed bandwidth that is always available even if no data is 
being sent. CBR traffic is generally time-sensitive (doesn't tolerate delay). CBR is used for 
connections that continuously require a specific amount of bandwidth. A PCR is specified and 
if traffic exceeds this rate, cells may be dropped. Examples of connections that need CBR 
would be high-resolution video and voice.
5.3.1.2  Variable Bit Rate (VBR) 
The Variable Bit Rate (VBR) ATM traffic class is used with bursty connections. Connections 
that use the Variable Bit Rate (VBR) traffic class is used with bursty connections.
5.3.1.3  Unspecified Bit Rate (UBR)
The Unspecified Bit Rate (UBR) ATM traffic class is for bursty data transfers. However, UBR 
doesn't guarantee any bandwidth and only delivers traffic when the network has spare 
bandwidth. An example application is background file transfer.
5.4  Internet Connection 
To change your ZyXEL Device’s WAN remote node settings, click Network > WAN > 
Internet Connection
. The screen differs by the encapsulation. 
See 
 for more information.