ConnectivityProblems

Version 6 (Adrian Georgescu, 07/21/2013 10:20 pm)

1 1 Adrian Georgescu
h1. Connectivity Problems
2 1 Adrian Georgescu
3 6 Adrian Georgescu
Sometimes real-time communication between end-points fails. What can be the reasons? Here is a short checklist to eliminate possible causes:
4 1 Adrian Georgescu
5 1 Adrian Georgescu
h2. Local Computer
6 1 Adrian Georgescu
7 5 Adrian Georgescu
 * Firewall software installed. Check if no software blocks access to the ports used by your application or enable the use of the proper ports in the firewall configuration.
8 1 Adrian Georgescu
9 2 Adrian Georgescu
h2. Internet Router
10 1 Adrian Georgescu
11 1 Adrian Georgescu
 * SIP ALG enabled. Check of the router has any so called SIP support and disabled it.
12 5 Adrian Georgescu
 * Firewall enabled. Check if no software blocks access to the ports used by your application or enable the use of the proper ports in the firewall configuration.
13 1 Adrian Georgescu
14 3 Adrian Georgescu
h2. Internet Provider
15 1 Adrian Georgescu
16 2 Adrian Georgescu
 * Policy that blocks either SIP signalling or RTP media. You can try use another SIP service provider that provides access over TCP or TLS instead of UDP or is using custom ports.
17 1 Adrian Georgescu
18 3 Adrian Georgescu
h2. SIP Service Provider
19 1 Adrian Georgescu
20 4 Adrian Georgescu
 * Eequires use of STUN protocol so that the SIP devices uses a public IP address in the Contact header. This is wrong and unreliable, such behaviour is explicitly discouraged by the "standards":http://projects.ag-projects.com/projects/blinkc/wiki/MostEncounteredProblems#SIP-Provider-requires-STUN
21 4 Adrian Georgescu
 * Some codecs are not supported. Instead of rejecting such sessions with an appropriate code, they simply won't answer.
22 4 Adrian Georgescu
23 4 Adrian Georgescu
24 4 Adrian Georgescu
25 1 Adrian Georgescu
26 1 Adrian Georgescu
27 1 Adrian Georgescu
28 1 Adrian Georgescu
29 1 Adrian Georgescu