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Chapter 11 Voice
P-2602HWLNI User’s Guide
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11.3.1 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 ZyXEL Device) so a server can decide the best method of delivery, that is
the least cost, fastest route and so on.
11.3.2 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.
5
11.3.2.1 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 a 6-bit DSCP field which
can define up to 64 service levels. The following figure illustrates the DS field.
DSCP is backward compatible with the three precedence bits in the ToS octet so that non-
DiffServ compliant, ToS-enabled network device will not conflict with the DSCP mapping.
Figure 101
DiffServ: Differentiated Service Field
The DSCP value determines the forwarding behavior, the PHB (Per-Hop Behavior), that each
packet gets across the DiffServ network. Based on the marking rule, different kinds of traffic
can be marked for different priorities of forwarding. Resources can then be allocated
according to the DSCP values and the configured policies.
11.3.3 VLAN
Virtual Local Area Network (VLAN) allows a physical network to be partitioned into multiple
logical networks. Only stations within the same group can communicate with each other.
Your ZyXEL Device can add IEEE 802.1Q VLAN ID tags to voice frames that it sends to the
network. This allows the ZyXEL Device to communicate with a SIP server that is a member of
the same VLAN group. Some ISPs use the VLAN tag to identify voice traffic and give it
priority over other traffic.
5.
The ZyXEL Device does not support DiffServ at the time of writing.
DSCP
(6-bit)
Unused
(2-bit)
Содержание P-2602HWLNI
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Страница 7: ...Safety Warnings P 2602HWLNI User s Guide 7...
Страница 8: ...Safety Warnings P 2602HWLNI User s Guide 8...
Страница 24: ...Table of Contents P 2602HWLNI User s Guide 24...
Страница 32: ...List of Figures P 2602HWLNI User s Guide 32...
Страница 38: ...List of Tables P 2602HWLNI User s Guide 38...
Страница 39: ...39 PART I Introduction Introducing the ZyXEL Device 41 Introducing the Web Configurator 49...
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Страница 60: ...Chapter 2 Introducing the Web Configurator P 2602HWLNI User s Guide 60...
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Страница 86: ...Chapter 5 Bandwidth Management Wizard P 2602HWLNI User s Guide 86...
Страница 98: ...Chapter 6 Status Screens P 2602HWLNI User s Guide 98...
Страница 99: ...99 PART III Network WAN Setup 101 LAN Setup 117 Wireless LAN 129 Network Address Translation NAT Screens 155...
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Страница 154: ...Chapter 9 Wireless LAN P 2602HWLNI User s Guide 154...
Страница 166: ...Chapter 10 Network Address Translation NAT Screens P 2602HWLNI User s Guide 166...
Страница 167: ...167 PART IV VoIP Voice 169 VoIP Trunking 211 Phone Usage 227...
Страница 168: ...168...
Страница 226: ...Chapter 12 VoIP Trunking P 2602HWLNI User s Guide 226...
Страница 230: ...Chapter 13 Phone Usage P 2602HWLNI User s Guide 230...
Страница 232: ...232...
Страница 264: ...Chapter 15 Firewall Configuration P 2602HWLNI User s Guide 264...
Страница 268: ...Chapter 16 Content Filtering P 2602HWLNI User s Guide 268...
Страница 274: ...Chapter 17 Introduction to IPSec P 2602HWLNI User s Guide 274...
Страница 309: ...Chapter 19 Certificates P 2602HWLNI User s Guide 309 Figure 173 My Certificate Details...
Страница 320: ...Chapter 19 Certificates P 2602HWLNI User s Guide 320 Figure 181 Trusted Remote Host Details...
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Страница 330: ...Chapter 20 Static Route P 2602HWLNI User s Guide 330...
Страница 338: ...Chapter 21 Bandwidth Management P 2602HWLNI User s Guide 338...
Страница 342: ...Chapter 22 Dynamic DNS Setup P 2602HWLNI User s Guide 342...
Страница 360: ...Chapter 23 Remote Management Configuration P 2602HWLNI User s Guide 360...
Страница 372: ...Chapter 24 Universal Plug and Play UPnP P 2602HWLNI User s Guide 372...
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Страница 380: ...Chapter 25 System P 2602HWLNI User s Guide 380...
Страница 406: ...Chapter 28 Troubleshooting P 2602HWLNI User s Guide 406...
Страница 422: ...Chapter 30 Diagnostic P 2602HWLNI User s Guide 422...
Страница 432: ...Chapter 31 Product Specifications P 2602HWLNI User s Guide 432...
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Страница 446: ...Appendix A Setting up Your Computer s IP Address P 2602HWLNI User s Guide 446...
Страница 482: ...Appendix F Legal Information P 2602HWLNI User s Guide 482...
Страница 488: ...Appendix G Customer Support P 2602HWLNI User s Guide 488...