The SIP Trunking Platform and SIP Inbound Platform provide a lot of information about the state of calls, both successful and failed. Below is a simple guide to understanding what the status and response codes mean, both to you, and the end-user.

Successful Calls

Status CodeStatus ReasonDescription
200OKIndicates the request was successfully connected

Failed Calls

Status CodeStatus ReasonDescription
404Not Found / No Route FoundThe number requested was not found. If this is an inbound call, suggest checking our PBX or CPE is configured to allow this number, and in the correct format (e164). For outbound calls, ensure the number is valid. If it is, please contact support.
486Busy HereCallee is Busy. There are a number of reasons for this to happen. Examples include: -
1. Handset the number is pointing to is in-use
2. Number of channels licensed on the CPE isn't enough 
487Request TerminatedRequest has terminated by bye or cancel.
This generally happens when the Caller hangs up before the Callee has answered the call.
500Internal Server ErrorThe server could not fulfil the request due to some unexpected condition.
This can happen for many reason, however the most common one is numbers are not configured on customer PBX/CPE.
603MaxPeak Cost ExceededThis will be generated by the Zapappi Outbound Platform. This specifically related to the maximum cost any call can incur, per minute (based on your most recent rate card). If you wish to have this limit increased, please contact support.

Terms Used

Callee: The person who receives the call

Caller: The person who makes the call

PBX: Customers phone system

CPE: Equipment connected to the SIP trunk (SBC etc)

SBC: Session Border Controller