Digi TransPort WR11 User Manual page 774

Configuring security
[tos]
The [tos] firewall script field specifies the Type of Service (TOS) to match. If included, the [tos] field
consists of the keyword tos followed by a decimal or hexadecimal code, identifying the type of service
to match.
For IPv6 packets, the traffic class field in the IPv6 header is checked.
For example, to block any inbound packet on PPP 0 with a TOS of 0, the rule is:
bl ock i n on ppp 0 t os 0
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Firewall
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