Snom 4S manual Table of Contents

Table of Contents

1	Overview	5
1.1	Applications	6
1.2	Features	6
2	Architecture	9
2.1	The NAT Filter and SIP	9
2.2	NAT	10
2.2.1	How does NAT work?..............................................................................................................................................11
2.2.2	Symmetrical RTP............................................................................................................................................................11
2.2.3	Signalling SIP.......................................................................................................................................................................11
2.2.4	Media RTP...................................................................................................................................................................................12
2.2.5	Classification of User Agents....................................................................................................................12
2.2.6	Probing Media Paths.................................................................................................................................................13
2.2.7	The Role of the NAT Filter..............................................................................................................................13
2.2.8	Optimizing the Media Path for Symmetrical NAT..................................................14
2.3	SBC Behaviour	15
2.3.1	Registering................................................................................................................................................................................15
2.3.3	RTP Relay....................................................................................................................................................................................16
2.4	Scaling and Redundancy	18
2.5	Detecting the right NAT Filter	19
2.6	Requirements on User Agents	20
2.6.1	Non NAT-Aware User Agents.....................................................................................................................20
2.6.2	STUN/ICE-Aware User Agents................................................................................................................20
2.7	Defining the Maximum Session Time	21
3	Installation	23
3.1	Windows	23
3.2	Linux	28
4	Configuration	31
4.1	Logging In	31
4.2	Port Binding	31
4.3	System Settings	33
4.3.1	Logging...........................................................................................................................................................................................33
4.3.2	Preparing Recovery ...................................................................................................................................................34
4.3.3	General Outound Proxy......................................................................................................................................34

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