Toshiba Strata CTX28 Programming Manual page 458

Applications, Tips and Tricks
IP Telephone Quality of Service (QoS) Programming
Priority Control Adjustments
This VoIP feature provides a framework in which voice traffic flowing on the network is prioritized over
other types of traffic. CTX supports two industry standard types of Priority control: IEEE802.1p and
Diffserv (Differentiated Services). These options should be enabled simultaneously so the voice packets
remain prioritized through the whole network path. IEEE802.1p prioritizes voice packets on the Ethernet
(LAN) level and DiffServ prioritizes voice packets that pass through the internet, intranet, etc.
Important!
To setup priority control from WinAdmin
1. Select IP Telephone > System IP Data
2. For Ethernet level (LAN) voice packet priority control.
Enable 07 IEEE802.1p
Set 08 IEEE802.1p. Configuration and set "voice" or "best effort", voice provides a higher level of
priority.
3. For IP level (Internet) voice packet priority control. Enable 03 DiffServ
Set 04 TOS Field Type (TOS -Type Of Service or DSCP - Differentiated Service code point)
Note The most common type used is TOS
If set to "TOS"
Set 05 "TOS Precedence type" (CRITIC/ECP ~ Routine) where CRITIC has the highest priority.
Set "TOS Delay type" (Normal or Low) – Low is the best service setting
Set "TOS Throughput" (Normal or High) – High is the best service setting
Set "TOS Reliability" (Normal or High) – High is the best service setting
IF set to "DSCP"
Set "06 DSCP" from 1~64, Basic setting should be one of the following:
0 = Best effort, The default setting for most IP traffic.
24 = Assured flow (AF) or Controlled Load, intended to classify streaming traffic.
40 = Expedited Flow (EF) or Guaranteed, intended to classify high priority traffic. Used by VoIP
gateways to mark VoIP traffic.
A-12
Priority Control processing has two requirements for it to work accurately. All network
Ethernet equipment connected to the BIPU LAN (routers, switches, etc.) must be in compli-
ance with IEEE802.1p voice packet prioritization. When going through a network provider
(ISP, etc.), the provider must support the DiffServ feature - contact your ISP for this service.
Strata CTX Programming - Part 4: Appendices 6/04