DiffServ
Issue 3.4.1 June 2005
317
Recommendations for end-to-end QoS
When end-to-end QoS is desired, Avaya recommends using
DiffServ
, a Layer 3 CoS method.
Modern can map DiffServ Code Points (DSCP) to 802.1p priority values, so 802.1p tags can be
recreated on each Ethernet link. This functionality is supported in Avaya Layer 3 switches, and
the X330 WAN module.
IEEE 802.1p states a standard according to which these bits are used for CoS. The precedence
is listed in
Table 73: IEEE 802.1 precedence and service mapping
.
DiffServ
The Differentiated Services (DiffServ) prioritization scheme redefines the existing TOS byte in
the IP header (
Figure 83: Differentiated Services (DiffServ) TOS byte
on page 318) by
combining the first 6 bits into 64 possible combinations. This use of the TOS byte is still
evolving, but can be used now by Communication Manager, IP Telephones, and other network
elements such as routers and switches in the LAN and WAN.
Table 73: IEEE 802.1 precedence and service mapping
User priority
Service mapping
000
Default, assumed to be best effort
001
Reserved, less than best effort
010
Reserved
011
Reserved
100
Delay sensitive, no bound
101
Delay sensitive, 100 ms bound
110
Delay sensitive, 10 ms bound
111
Network control
Summary of Contents for Application Solutions
Page 1: ...Avaya Application Solutions IP Telephony Deployment Guide 555 245 600 Issue 3 4 1 June 2005 ...
Page 20: ...About This Book 20 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 21: ...Issue 3 4 1 June 2005 21 Section 1 Avaya Application Solutions product guide ...
Page 22: ...22 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 106: ...Call processing 106 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 124: ...Avaya LAN switching products 124 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 139: ...Issue 3 4 1 June 2005 139 Section 2 Deploying IP Telephony ...
Page 140: ...140 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 186: ...Traffic engineering 186 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 204: ...Security 204 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 228: ...Avaya Integrated Management 228 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 274: ...Reliability and Recovery 274 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 275: ...Issue 3 4 1 June 2005 275 Section 3 Getting the IP network ready for telephony ...
Page 276: ...276 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 356: ...Network recovery 356 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 366: ...Network assessment offer 366 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 367: ...Issue 3 4 1 June 2005 367 Appendixes ...
Page 368: ...Appendixes 368 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 394: ...Access list 394 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 414: ...DHCP TFTP 414 Avaya Application Solutions IP Telephony Deployment Guide ...