Plan a Staged, Prioritized Deployment
Deploying decryption can change the reachability of websites
that users may be used to accessing if those sites are risky or
don’t support your business. A staged rollout prepares the user
population and tech support for changes, and enables you to test
how the rollout affects applications.
Plan to roll out decryption in a controlled manner,
piece by piece. Don’t roll out your entire decryption deployment
at one time. Test and ensure that decryption is working as planned
and that users understand what you are doing and why. Rolling out
decryption in this manner makes it easier to troubleshoot in case anything
doesn’t work as expected and helps users adjust to the changes.
Educating stakeholders, employees, and other users such as contractors
and partners is critical because decryption settings may change
their ability to access some websites. Users should understand how
to respond to situations in which previously reachable websites
become unreachable and what information to give technical support.
Support should understand what is being rolled out when and how to
help users who encounter issues. Before you roll out decryption
to the general population:
- Identify early adopters to help champion decryption and
who will be able to help other employees who have questions during
the full rollout. Enlist the help of department managers and help
them understand the benefits of decrypting traffic.
- Set up proof-of-concept (POC) trials in each department with
early adopters and other employees who understand why decrypting
traffic is important. Educate POC participants about the changes
and how to contact technical support if they run into issues. In
this way, decryption POCs become an opportunity to work with technical
support to POC how to support decryption and to develop the most
painless method for supporting the general rollout. The interaction
between POC users and technical support also allows you to fine-tune
policies and how to communicate with users.
POCs enable you to
experiment with prioritizing what to decrypt first, so that when
you phase in decryption in the general population, your POC experience
helps you understand how to phase in decrypting different URL Categories. Measure
the way decryption affects firewall CPU and memory utilization to
help understand if the firewall sizing is correct or if you need
to upgrade. POCs can also reveal applications that break decryption
technically (decrypting them blocks their traffic) and need to be
added to the Decryption Exclusion list.
When you set up POCs,
also set up a user group that can certify the operational readiness
and procedures prior to the general rollout.
- Educate the user population before the general rollout, and
plan to educate new users as they join the company. This is a critical
phase of deploying decryption because the deployment may affect
websites that users previously visited but are not safe, so those
sites are no longer reachable. The POC experience helps identify
the most important points to communicate.
- Phase in decryption. You can accomplish this several ways. You
can decrypt the highest priority traffic first (for example, the
URL Categories most likely to harbor malicious traffic, such as
gaming) and then decrypt more as you gain experience. Alternatively,
you can take a more conservative approach and decrypt the URL Categories
that don’t affect your business first (so if something goes wrong,
no issues occur that affect business), for example, news feeds.
In all cases, the best way to phase in decryption is to decrypt
a few URL Categories, take user feedback into account, run reports
to ensure that decryption is working as expected, and then gradually
decrypt a few more URL Categories and verify, and so on. Plan to
make Decryption
Exclusions to exclude sites from decryption if you can’t
decrypt them for technical reasons or because you choose not to
decrypt them.
If you
Enable
Users to Opt Out of SSL Decryption (users see a response
page that allows them either to opt out of decryption and end the session
without going to the site or to proceed to the site and agree to
have the traffic decrypted), educate them about what it is, why
they’re seeing it, and what their options are.
- Create realistic deployment schedules that allow time to evaluate
each stage of the rollout.
Place firewalls in positions where they can see all of
the network traffic so that no encrypted traffic inadvertently gains
access to your network because it bypasses the firewall.
