Technical data

4. Packages
F8
o
21
3 4 5 6
F1 F2
F3 F4 F5 F6
F7
level 2
level 3
level 1
level 0
Figure 4.9.: Example 3
is for a second client PC divided in 2/3 http and 1/3 for the rest (2/6 and 1/6 of the whole
bandwidth) this would happen: If both clients run at full load both get their half of the
bandwidth. If the second one is not transferring http 2/6 of unused bandwidth are distributed
not only to the second but to both PCs as decribed above. To avoid this subclasses are created.
Traffic of a class is at first distributed to its subclasses. Only if they don’t use the complete
traffic the rest is spread to the other classes. In the picture the areas that belong together are
encircled (red = 1, blue = 2, green = 5 and orange = 6.
Example 4
Configuration for ACK packet priorization in order to keep downstream high if upstream has
heavy load:
OPT_QOS='yes'
QOS_INTERNET_DEV_N='1'
QOS_INTERNET_DEV_1='ppp0'
QOS_INTERNET_BAND_DOWN='768Kibit/s'
QOS_INTERNET_BAND_UP='128Kibit/s'
QOS_INTERNET_DEFAULT_DOWN='0'
QOS_INTERNET_DEFAULT_UP='2'
Configure ppp0 as the Internet device (DSL) and give it the usual up/downstream bandwidth
for TDSL (and some other providers). It may be necessary to lower upstream bandwidth for
some Kibibit for the trying.
No classes for downstream should be defined:
QOS_INTERNET_DEFAULT_DOWN='0'
217