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Understanding and Using DISA

Cannon VoIP3 min read

DISA (Direct Inward System Access), also called company dial-in calling, lets you call into your Cannon VoIP phone system from any outside phone and then dial out as the company. The person you call sees your company's main number, whether you're on a cell phone, in a hotel room, or at any line you happen to be near.

How DISA works

You call in, enter the company dial-in PIN, and then dial the number you want to reach. The call goes out through your phone system, so it shows the company's main number instead of your personal cell. Recent dial-in activity is listed on the Feature Codes page in the portal, so you can always see how DISA is being used.

DISA is protected by a PIN because it lets an outside caller place calls on your account. The company dial-in PIN is 6 to 10 digits and is set by your admin in the portal. Easy PINs like 123456 are refused.

Making an outbound call with DISA

1
Call in
From any outside phone, call your company's dial-in number. Your admin can tell you which number to use.
2
Enter the company dial-in PIN
Type the 6 to 10 digit PIN when prompted.
3
Dial the number you want to call
Enter the destination number, just as you would from your desk.
4
Talk as the company
The person you call sees your company's main number, not your cell phone.

Checking voicemail remotely

DISA is only for calling out. Voicemail has its own way in. From your own desk phone or app, just dial *98 to hear new messages first. From any other phone, follow these steps:

1
Turn on outside access (one time)
Outside voicemail access is off until you turn it on in the portal. It needs its own PIN of 6 to 8 digits, and easy PINs like 123456, repeated digits or your extension number are refused.
2
Call your own number
From any phone, dial your own direct number and let it go to your voicemail greeting.
3
Press * during your greeting
Star only works while your greeting plays, never while a caller is leaving a message.
4
Enter your PIN
Type your outside access PIN. Repeated wrong PINs lock outside access for an hour.
5
Listen to your messages
Press 7 to erase, 9 to save, and # for the next message.

Your regular mailbox PIN is 4 to 8 digits and is set in the portal next to your extension's other settings. Every voicemail is also transcribed with a one-line summary and can be emailed to you, so you can often read a message without dialing in at all.

Security best practices

Treat your DISA PIN like a bank PIN. Because DISA can place outbound calls on your account, an exposed PIN could lead to fraudulent long-distance charges.

  • Use a complex, unique PIN. Easy PINs like 123456 are refused, but avoid anything else guessable too.
  • Never share it, and don't write it somewhere easy to find.
  • Check recent dial-in activity on the Feature Codes page. Unusual dial-in calling is flagged as a possible leaked PIN.
  • If you think it's been compromised, change it in the portal right away, or contact us and we'll help.

Need help with DISA?

We'll help you set it up and choose a strong PIN. Reach out any time.

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