Internet connection requirements - EN

Recommended firewall settings on customer's router

#ProtokolTransportIP:Port(y)Traffic directionNote
1SIPUDPPBX_hostname:5060Outgoing, Incoming*Call signaling

PBX_hostname:5004 - 20000** (Aastra/Grandstream)

Outgoing, Incoming*Media
5HTTPSTCPPBX_hostname:8089Outgoing, Incoming*Communicator App
7STUN/TURNTCP,UDP212.71.175.51,, 3479, 5349Outgoing, Incoming*Support for NAT traversal
8HTTPSTCPPBX_hostname: 443Outgoing, Incoming*Web interface (UI)
9NTPTCP,UDP212.71.128.13:123,, Incoming*Time server

*) Incoming communication within an already established connection, comes from PBX (service) from the specified source port.

**) Depends on end device, described example is for Aastra a Grandstream.

Communicator application (

Google Firebase database serviceThe service establishes a websocket connection
Voice traffic - dataDTLS-SRTPEncrypted voice communicationIP_PBX:dynamic  port  ( Can be limited by Chrome policy )
Voice traffic - signalingWebSocketEncrypted call signalingIP_PBX:8089
WEBCOM APIhttps://webcom.ipex.czWebcom application and API
B2B APIhttps://restapi.ipex.czB2B API
PBX API (,, API for management
Statisticshttps://ipbx-stats.voipex.ioCall center statistics
Meetings APIhttps://meeting.voipex.ioAPI for videoconferencing
Amazon S3
User photos

Web application for pbx management (

NameDomainDescriptionIP addresses
Google Charts for plotting call center statistics
Google Analyticshttps://google-analytics.comStatistics on the use of platform modules
CDNhttps://cdnjs.cloudflare.comCDN pro javascript knihovny (Bootstrap, Angular)
CDN IPEXhttps://cdn.ipex.czCDN for javascript libraries (Bootstrap, Angular)
PBX APIhttps://ipbxapi.voipex.ioPBX API pro management of PBXs
B2B APIhttps://restapi.voipex.ioB2B API

SIP connector (SIP trunk)

Definition on central PBX IPEX:

ProtocolTransportPortsCodecsTraffic direction
SIPUDP5060G.711a, G.729, G.722, H.264IN/OUT
RTPUDP5000-20000G.711a, G.729, G.722, H.264IN/OUT

Wallboard (

NameDomainDescriptionIP addresses
PBX APIhttps://ipbxapi.voipex.ioPBX API for management PBXs

Requirements for calls to the quality of the Internet line

DelayITU-T G.114< 150 msNetwork packet delivery delay
< 30 msVariation in the amount of packet delay when passing through networks
Packet loss
< 1 %Number of packets lost in percent
90KbpsData bandwidth for one speech channel (symmetrical, G711 codec)

Requirements for video conferencing calls - bandwidth

Theoretically, there is no minimum data rate for video calls, as the picture quality is automatically adjusted to the current capacity of the Internet connection (ie it can change during the call), however, the following applies to maintain a certain quality:

  • 1: 1 video calling - 600kbps (up / down) for HQ quality and 1.2Mbps (up / down) for HD quality
  • For group video calling: 600kbps / 1.2Mbps (up / down). For tile display: 1.5Mbps / 1.5Mbps (up / down). 
  • Screen sharing only (no video thumbnails): 50-75kbps
  • To share the screen with video thumbnails: 50-150kbps