re outside of the mesh. For external services, Istio provides two
options, first to block all external service access (enabled by setting
<code>global.outboundTrafficPolicy.mode</code> to <code>REGISTRY_ONLY</code>) and
second to allow all access to external service (enabled by setting
<code>global.outboundTrafficPolicy.mode</code> to <code>ALLOW_ANY</code>). The default option for this
setting (as of Istio 1.3) is to allow all external service access. This
option can be configured via <a href=/v1.8/docs/re