The customer has reported a dropped call issue: The call disconnected, becoming inactive, on its own without being prompted by either user, stopping the call timer.  If the call timer kept running, that means the call was not dropped but rather lost audio.  Refer to silence/loss of audio troubleshooting.

Information Gathering

 Troubleshooting

Information to gather from the customer:

1. Circumstances of the call–Think in terms of Who, What, When, Where and How:
   1. Who: The parties involved, usually an Originating Party who called out to a Terminating Party
      1. Originating Party (calling number):
      2. Terminating Party (called number):
      3. Scope of the issue:  How many users are experiencing dropped calls?
         1. Single user
         2. Multiple users
         3. All users
            1. Site-wide
            2. Enterprise-wide
   2. What: The context of the call.  Inbound?  Outbound? Internal? External? Is it only certain kinds of calls, or is it all calls?
      1. Direction (Outbound vs. Inbound): Are calls dropping on only outbound calls, only inbound calls, or both?
      2. Endpoint: Method of placing and receiving call
         1. Deskphone:
            1. Manufacturer: Polycom, Yealink, Cisco or other?
            2. Primary Device or SCA?
            3. Hotel/Open Seating host
         2. Remote Office
         3. Softphone
            1. UC-One
            2. Skype
            3. Teams
      3. Application: Was any call tracking application in use?
         1. Unity
         2. ECS
         3. Call center
         4. Receptionist
      4. Detailed, step-by-step sequence of user's actions and experience on the call
      5. Any additional details pertinent to the call (Was the user transferred or put on hold?)
         • Any error messages on the phone or application?
   3. When: Was this a one-time occurrence, intermittent or persistent with every call?  Try to get a specific call example.
      1. Date:
      2. Time (including time zone): 
      3. When did the issue start?
         1. Today at a specific time
         2. Previous day
         3. Does this happen at a certain time of day?
            • If at certain times, could be due to call volume (connection bandwidth) or network issues (network saturation or QoS issues)
         4. Has never worked since implementation
      4. Does the call drop after a certain period of time, such as after ten minutes?  Does the issue occur only on longer calls?  If so, and the user's remote, this could indicate an issue with Stateful Inspection on the local network's firewall.  Provide firewall guide.
      5. Frequency
         1. Every call?
         2. Intermittent?
         3. Can it be replicated?
   4. Where: Location of each party. 
      1. Remote or in an office behind an Edgewater? (Ask the user, "Are you in the office or remote/at home?")
         • Check phone in OCOM to see what IP address it's registering from.  If the IP can't be found in Nagios, it's probably remote.
      2. Does Evolve own the numbers involved or are they off-platform numbers owned by another carrier? (Some troubleshooting may be necessary to determine this)
   5. How: How was the call initiated?
      1. Direct call: Originating Party dialed Terminating Party directly
      2. Queued call: The call was presented to the Terminating Party through a call center.
      3. Transfer: The Originating Party reached a Terminating Party, then was transferred to a secondary Terminating Party.
2. Obtain a call example - Call Examples must be from within the past 24 hours so that if needed they can be investigated with underlying carriers.
   • Caller:
   • Callee:
   • Time/Date (including Time Zone):

• Call Example Verbiage:

To facilitate troubleshooting the reported issue, a call example is required. 

Please provide us with a specific, recent call example (from within the last 24 hours) of the reported issue, so we can verify its routing and quality.

Please include the following information:

Caller number: 
Callee number: 
Date and time (including time zone): 
Issue description:

**************************Your ticket is now being placed on a HOLD status pending the requested information.

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Troubleshooting

1. Find the call example in OCOM and document the call example and PCAP in the ticket.
   1. For customers with managed T1 circuits (On-Net), we are responsible for ensuring call quality, since we have direct control over their Broadband connection. For customers without a managed circuit from EvolveIP (Bring Your Own Broadband), we are unable to ensure the same level of quality. Also, we tag our VOIP packets for QoS but some ISPs ignore these tags and voice data is treated the same as all other traffic.  Therefore, with call quality tickets, it is a good idea to check Nagios. Especially for customers with managed circuits, we can check for latency or packet loss and open a ticket with the carrier to investigate.
   2. For customers without managed circuits (Off-Net), we can still look at packet loss and latency, but then advise them of our findings so they can take that information to their ISPs.
   3. OCOM
      1. Search by the offnet number.  This is the best way to make sure you get all the legs of a call.  Can search under "User Tracking" or "Calls."
      2. Calls from a softphone like UC-One or ECS will show as inbound.
      3. Identify any SIP errors that could have caused the call to drop (404, 603, etc.)  Common SIP errors:
         • 403: Forbidden
         • 404: Not Found
         • 408: Request Timeout - If preceded by a bunch of invites, it's probably their network timing out
         • 480: Temporarily Unavailable
         • 500: Internal Server Error
         • 503: Service Unavailable
         • 600: Busy Everywhere
         • 603: Decline
      4. Was the user's phone registered at the time of the call?
         1. If not, why did the registration fail?  Are we getting proper SIP messaging from their gateway?  If not, the customer must investigate their gateway.  If they're remote, provide the Home User Guide and ensure SIP inspect/SIP ALG is disabled
      5. Who sent the first BYE?
         1. If it was the carrier, open a ticket with that carrier to investigate
         2. If it was the user's gateway, the customer must investigate their gateway.  If they're remote, provide the Home User Guide and ensure SIP inspect/SIP ALG is disabled
      6. Does the call drop after a certain period of time, such as after ten minutes?  Does the issue occur only on longer calls?  If so, and the user's remote, this could indicate an issue with Stateful Inspection on the local network's firewall.  Provide firewall guide.
   4. For customers that have dedicated call recording servers, we can pull their recordings and listen to locate the disconnect (Note: Don't mention this to the customer, though.  This is just a troubleshooting step on our side) - List of customers that have dedicated servers: Orecx Call Recording Server List
2. When to send to Tier 2:
   1. Chronic, replicatable issues for which the client pushes back that the issue's on us or they don't believe the issue is from off our platform
   2. Issues that can't be resolved with Tier 1 resources (always present issue in the group chat and check with team leads before elevating to Tier 2)
   3. If the customer's listed on Orecx Call Recording Server List, you can mention this to Tier 2, that recordings can be pulled, but again, don't mention this to the customer.

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