These keywords in CAKE have been provided to represent a number of common link technologies:

Write the keyword below
***********************
"conservative"     Failsafe     (overhead 48 atm)
"ethernet"         Ethernet     (overhead 38 mpu 84 noatm)
"docsis"           Cable Modem  (overhead 18 mpu 64 noatm)
"pppoe-ptm"        VDSL2        (overhead 30 ptm)
"bridged-ptm"      VDSL2        (overhead 22 ptm)
"pppoa-vcmux"      ADSL         (overhead 10 atm)
"pppoa-llc"        ADSL         (overhead 14 atm)
"pppoe-vcmux"      ADSL         (overhead 32 atm)
"pppoe-llcsnap"    ADSL         (overhead 40 atm)
"bridged-vcmux"    ADSL         (overhead 24 atm)
"bridged-llcsnap"  ADSL         (overhead 32 atm)
"ipoa-vcmux"       ADSL         (overhead 8  atm)
"ipoa-llcsnap"     ADSL         (overhead 16 atm)

# If you are unsure, then write "conservative" as a general safe value.
# "raw" keyword turns off all overhead compensation in CAKE.

"ether-vlan" keyword information:

"ether-vlan" adds '4 bytes' to the overhead.

- This keyword is not for standalone use, but act as a modifier to some previous presets or keywords.
- In addition to those previous presets or keywords it is common to have VLAN tags (4 extra bytes) or PPPoE encapsulation (8 extra bytes).
# This keyword "ether-vlan" may be repeated as necessary.

For true ATM links (ADSL), one often can measure the real per-packet overhead empirically, see for further information how to do that:

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