Configuring QoS settings
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Audio
Six bit binary field for prioritizing audio data
packets on the network. Do not alter these settings unless
you need to.
Video
Six bit binary field for prioritizing video data
packets on the network.
ToS configuration ToS configuration represents a tradeoff between the abstr act parameters of precedence, delay,
throughput, and reliability.
ToS uses six out of a possible eight bits. The ISDN Gateway allo ws you to set bits 0 to 5, and will place
zeros for bits 6 and 7.
Bits 0-2 set IP precedence (the priority of the packet).
Bit 3 sets delay: 0 = normal delay, 1 = low delay.
Bit 4 sets throughput: 0 = normal throughput, 1 = high throughput.
Bit 5 sets reliability: 0 = norm al reliability, 1 = high reliability.
Bits 6-7 are reserved for future use and cannot be set using the ISDN Gateway interface.
You need to create a balance by assigning priority to audi o and video packets whilst not causing undue
delay to other packets on the network. For example, do not set every value to 1.
DiffServ configuration DiffServ uses six out of a possible eight bits to set a codepoi nt. (There are 64 possible codepoints.) The
ISDN Gateway allows you to set bits 0 to 5, and will place zeros for bits 6 and 7. The codepoint is
interpreted by DiffServ nodes to determine how the packet is treated.
Default settings The default settings for QoS are:
Audio 101110:
o For ToS, this means IP precedence is set to 5 giving relat ively high priority. Delay is set
to low, throughput is set to high, and reliability is set to normal.
o For Diff Serv, this means expedited forwarding.
Video 100010:
o For ToS, this means IP precedence is set to 4 giving quite high prior i t y (but not quite as
high as the audio precedence). Delay is set to normal, throug hput is set to high, and
reliability is set to normal.
o For DiffServ, this means assured forwarding (codepoint 41) .
To return the settings to the default settings, click Reset to default.