Acceptable Delay
International Telecommunication Union Telecommunication Standardization Sector
(ITU-T) specifies arrangement adjournment for articulation applications in Advocacy G.114. This
recommendation defines three bands of one-way delay, as apparent in Table 2-1.
Acceptable Delay: G.114
Range in Milliseconds Description
0 to 150 Adequate for best user applications.
150 to 400 Acceptable, provided administrators are acquainted of the transmission
time and its appulse on the manual affection of user
applications.
Above 400 Unacceptable for accepted arrangement planning purposes. (However, it
is accustomed that in some aberrant cases, this absolute will be
exceeded.)
Chapter 2: Considering VoIP Design Elements 59
Note This advocacy is for access with answer that are abundantly controlled,
implying that answer cancellers are used. Answer cancellers are appropriate back one-way delay
exceeds 25 ms (G.131).
The G.114 advocacy is aggressive against civic telecommunications administrations
and, therefore, is added acrimonious than recommendations that would commonly be
applied in clandestine articulation networks. Back the area and business needs of end users are
well accepted to a arrangement designer, added adjournment ability prove acceptable. For clandestine networks,
a 200 ms adjournment is a reasonable ambition and a 250 ms adjournment is a limit. This ambition is what
Cisco Systems proposes as reasonable as continued as boundless jitter does not affect voice
quality. However, all networks charge be engineered so the best accepted articulation connection
delay is accepted and minimized.