
Chapter 9 Voice
P-2812HNU-51c User’s Guide
198
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 P-2812HNU-51c) so a server can decide the best
method of delivery, that is the least cost, fastest route and so on.
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 (DSCP) 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.
3
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 89
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.
3.
The P-2812HNU-51c does not support DiffServ at the time of writing.
DSCP
(6-bit)
Unused
(2-bit)
Summary of Contents for P-2812HNU-51c
Page 2: ......
Page 8: ...Safety Warnings P 2812HNU 51c User s Guide 8 ...
Page 10: ...Contents Overview P 2812HNU 51c User s Guide 10 ...
Page 19: ...19 PART I User s Guide ...
Page 20: ...20 ...
Page 73: ...73 PART II Technical Reference ...
Page 74: ...74 ...
Page 88: ...Chapter 4 Status Screens P 2812HNU 51c User s Guide 88 ...
Page 118: ...Chapter 5 WAN Setup P 2812HNU 51c User s Guide 118 ...
Page 204: ...Chapter 9 Voice P 2812HNU 51c User s Guide 204 ...
Page 210: ...Chapter 10 File Sharing P 2812HNU 51c User s Guide 210 ...
Page 216: ...Chapter 11 Firewall P 2812HNU 51c User s Guide 216 ...
Page 223: ...Chapter 12 Certificate P 2812HNU 51c User s Guide 223 Figure 99 Certificate Details ...
Page 232: ...Chapter 13 Static Route P 2812HNU 51c User s Guide 232 ...
Page 236: ...Chapter 14 Policy Forwarding P 2812HNU 51c User s Guide 236 ...
Page 252: ...Chapter 16 Quality of Service QoS P 2812HNU 51c User s Guide 252 ...
Page 274: ...Chapter 19 Universal Plug and Play UPnP P 2812HNU 51c User s Guide 274 ...
Page 284: ...Chapter 21 Interface Group P 2812HNU 51c User s Guide 284 ...
Page 288: ...Chapter 22 System Settings P 2812HNU 51c User s Guide 288 ...
Page 292: ...Chapter 23 Logs P 2812HNU 51c User s Guide 292 ...
Page 300: ...Chapter 24 Tools P 2812HNU 51c User s Guide 300 ...
Page 320: ...Chapter 27 Product Specifications P 2812HNU 51c User s Guide 320 ...
Page 336: ...Appendix A Network Troubleshooting P 2812HNU 51c User s Guide 336 ...
Page 376: ...Appendix C Pop up Windows JavaScripts and Java Permissions P 2812HNU 51c User s Guide 376 ...
Page 388: ...Appendix D IP Addresses and Subnetting P 2812HNU 51c User s Guide 388 ...