Network Configuration Concepts
211
Bandwidth management and call admission control can be used to ensure that voice quality is
maintained in parts of the network where there may be bandwidth constraints. For details, refer
to “Bandwidth, Bandwidth Management, Codecs and Compression” on page 171.
Refer to the
3300 ICP
Resiliency
guide for detailed calculations and breakdown of signalling
messages for different connections.
SERIALIZATION DELAY
Serialization delay happens because data is queued in a particular device, but cannot be sent
because another packet is currently being sent. In a fast link, such as in the LAN, the delay is
fairly small (a few milliseconds) and is easily resolved with the end-device jitter buffer.
However, in a WAN access connection, the data rate is not as high as within the LAN. In this
case, the waiting delay increases as the data rate reduces. If a particularly large packet (for
example, 1500 bytes) is being sent, then other devices must wait until it has gone before they
can gain access.
The IP phone and gateway devices are capable of handling delay variations (jitter) up to high
limits. However, in order to maintain the best voice quality performance, this variation should
be kept below 30 ms, with an ideal limit of 20 ms. The following figure shows waiting delay
against link speed, as well as against maximum transmission units (MTU). The value for MTU
can be programmed in routers so that packets with a payload greater than this number can be
reduced in size. The graph shows that when a packet of 1500 bytes is sent, a data-rate of about
700 kbps is needed on the WAN link in order to meet the ideal 20 ms limit.
Figure 29: Serialization delay Frame Relay
Summary of Contents for MiVOICE BUSINESS
Page 1: ...Mitel MiVoice Business RELEASE 7 2 ENGINEERING GUIDELINES ...
Page 15: ...Chapter 1 ABOUT THIS DOCUMENT ...
Page 16: ......
Page 22: ...Engineering Guidelines 8 ...
Page 23: ...Chapter 2 SYSTEM OVERVIEW ...
Page 24: ......
Page 28: ...Engineering Guidelines 14 ...
Page 29: ...Chapter 3 TYPICAL CONFIGURATIONS ...
Page 30: ......
Page 73: ...Chapter 4 PHONES AND VOICE APPLICATIONS ...
Page 74: ......
Page 95: ...Phones and Voice Applications 81 Figure 9 ICP Connection Paths and Limitations ...
Page 100: ...Engineering Guidelines 86 ...
Page 101: ...Chapter 5 POWER ...
Page 102: ......
Page 128: ...Engineering Guidelines 114 ...
Page 129: ...Chapter 6 PERFORMANCE ...
Page 130: ......
Page 135: ...Chapter 7 APPLICATIONS ...
Page 136: ......
Page 142: ...Engineering Guidelines 128 ...
Page 143: ...Chapter 8 EMERGENCY SERVICES ...
Page 144: ......
Page 151: ...Chapter 9 IP NETWORKING ...
Page 152: ......
Page 167: ...Chapter 10 LICENSING ...
Page 168: ......
Page 183: ...Chapter 11 BANDWIDTH CODECS AND COMPRESSION ...
Page 184: ......
Page 209: ...Chapter 12 NETWORK CONFIGURATION CONCEPTS ...
Page 210: ......
Page 244: ...Engineering Guidelines 230 ...
Page 245: ...Chapter 13 NETWORK CONFIGURATION SPECIFICS ...
Page 246: ......
Page 309: ...Appendix A CAT 3 WIRING ...
Page 310: ......
Page 315: ...CAT 3 Wiring 301 Figure 55 CX MX MXe AX and LX Minimum Cable Standard ...
Page 316: ...Engineering Guidelines 302 ...
Page 317: ...Appendix B INSTALLATION EXAMPLES ...
Page 318: ......
Page 335: ...Appendix C LLDP AND LLDP MED CONFIGURATION EXAMPLES ...
Page 336: ......
Page 347: ...Appendix D VOIP AND VLANS ...
Page 348: ......
Page 353: ...Appendix E VOIP SECURITY ...
Page 354: ......
Page 381: ... ...