Phone system (VoIP): what it is and how it is attacked
Runs the organisation's telephone calls over the network.
Also known as
- VoIP
- PBX
- telephony server
Typing any of them into the editor finds this object.
Why it matters on a security diagram
Often managed separately from IT and forgotten in reviews, while sitting on the same network as everything else.
How it gets attacked, and what reduces it
How it gets attacked
- Default administrator credentials
- Call routing abused to place expensive calls at your cost
What reduces it
- Change default credentials on the call platform
- Agree a verification step for any request that arrives by voice, because caller display can be set to anything
- Restrict call routing so it cannot be used to place expensive calls
Where it sits
- Group
- Servers · Machines that run something for other machines.
- Whose side, by default
- Ours · Belongs to the organisation the diagram is about.
- Catalogue identifier
- telephony
Reviewed . CC BY 4.0.
Others in servers
- Serverhost · machineA computer that runs something for other computers.
- Web serverHTTP server · websiteThe computer that sends your website to anybody who visits it.
- Application serverbackend · business logic tierRuns the working parts of an application, behind the website.
- DatabaseDB · SQL server · data storeStores the organised information an application depends on.
- Mail serveremail server · Exchange · SMTPSends, receives and stores the organisation's email.
- Name serverDNS · domain name serverTranslates names like example.com into network addresses.
- File serverSMB server · network shareHolds shared documents everyone can reach over the network.
- Virtual machine hosthypervisor · ESXi · Hyper-VOne physical server pretending to be many.
- Jump hostbastion · jump box · hardened admin hostThe single controlled machine administrators go through to reach sensitive systems.
- Backup serverbackup · Veeam · backup controllerMakes and manages the spare copies of your data that let you recover after something goes wrong.
- Update serverWSUS · patch server · software distributionDistributes software updates to every machine.
- Build pipelineCI/CD · Jenkins · GitHub ActionsThe automated production line that turns written code into the software the business actually runs.
The servers group lists all 13 of them side by side.
Phone system on your own diagram
Open the editor, press N, and type VoIP. The object is placed and connected to whatever was selected, and Tab adds the next one already joined to it. Nothing is uploaded: the page is served with a Content Security Policy that forbids the browser from making any outbound request at all.
Open the diagram maker