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Sustained Cell Rate (SCR) is the mean cell rate of each bursty traffic source. It
specifies the maximum average rate at which cells can be sent over the virtual
connection. SCR may not be greater than the PCR.
Maximum Burst Size (MBS) is the maximum number of cells that can be sent at
the PCR. After MBS is reached, cell rates fall below SCR until cell rate averages to
the SCR again. At this time, more cells (up to the MBS) can be sent at the PCR
again.
If the PCR, SCR or MBS is set to the default of "0", the system will assign a
maximum value that correlates to your upstream line rate.
The following figure illustrates the relationship between PCR, SCR and MBS.
Figure 35
Example of Traffic Shaping
6.5.1 ATM Traffic Classes
These are the basic ATM traffic classes defined by the ATM Forum Traffic
Management 4.0 Specification.
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.
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 can be grouped into
real time (VBR-RT) or non-real time (VBR-nRT) connections.
Summary of Contents for P-660N-T1A
Page 2: ......
Page 8: ...Safety Warnings P 660N T1A User s Guide 8...
Page 10: ...Contents Overview P 660N T1A User s Guide 10...
Page 18: ...Table of Contents P 660N T1A User s Guide 18...
Page 19: ...19 PART I User s Guide...
Page 20: ...20...
Page 50: ...Chapter 4 Tutorials P 660N T1A User s Guide 50...
Page 51: ...51 PART II Technical Reference...
Page 52: ...52...
Page 84: ...Chapter 6 WAN Setup P 660N T1A User s Guide 84...
Page 98: ...Chapter 7 LAN Setup P 660N T1A User s Guide 98...
Page 146: ...Chapter 9 Network Address Translation NAT P 660N T1A User s Guide 146...
Page 150: ...Chapter 10 Firewall P 660N T1A User s Guide 150...
Page 160: ...Chapter 12 Static Route P 660N T1A User s Guide 160...
Page 200: ...Chapter 18 CWMP P 660HN T1A User s Guide 200...
Page 222: ...Chapter 21 Tools P 660N T1A User s Guide 222...
Page 232: ...Chapter 23 Troubleshooting P 660N T1A User s Guide 232...
Page 240: ...Chapter 24 Product Specifications P 660N T1A User s Guide 240...
Page 278: ...Appendix B IP Addresses and Subnetting P 660N T1A User s Guide 278...
Page 288: ...Appendix C Pop up Windows JavaScripts and Java Permissions P 660N T1A User s Guide 288...
Page 320: ...Index P 660N T1A User s Guide 320...
Page 321: ...Index P 660N T1A User s Guide 321...
Page 322: ...Index P 660N T1A User s Guide 322...