This signifies the networking tier used for configuring this
address and can only take the following values: PREMIUM or
STANDARD. Internal IP addresses are always Premium Tier; global
external IP addresses are always Premium Tier; regional external
IP addresses can be either Standard or Premium Tier. If this
field is not specified, it is assumed to be PREMIUM.
Values:
UNDEFINED_NETWORK_TIER (0):
A value indicating that the enum field is not
set.
FIXED_STANDARD (310464328):
Public internet quality with fixed bandwidth.
PREMIUM (399530551):
High quality, Google-grade network tier,
support for all networking products.
STANDARD (484642493):
Public internet quality, only limited support
for other networking products.
STANDARD_OVERRIDES_FIXED_STANDARD (465847234):
(Output only) Temporary tier for FIXED_STANDARD when fixed
standard tier is expired or not configured.
