1. Overview

The following table provides an overview of the functionality of Nconnect Voice and the supported features.

Feature	Value	Notes
Calling Line Identification (CLIP)	yes	CLIP / CLIR needs to be set as specified on the PBX per call; There is no persistent setting on the trunk side
Calling Line Restriction (CLIR)	yes	CLIP / CLIR needs to be set as specified on the PBX per call; There is no persistent setting on the trunk side
CLIP no screening	yes	Off by default; Needs to be enabled on customer's request; Customer must have a permission to signal the desired phone number according to national law
DTMF	Inband (RTP) & Outband (RFC2833)
Emergency Calls	Based on geographical information of the assigned phone number	Identified by target number and routed based on geographical location of the associated number block
Fax	T.38 & G711
IP Standard	IPv4
Phone number	One geographical number block per trunk	New number blocks or porting of existing numbers are both supported; Verification of location needed according to national law
Registar	trunk.cloud-cfg.com	Please always use the FQDN of the registrar with the proper port configuration (trunk.cloud-cfg.com:5060) for setup of the PBX as used IPs might change over time
Security	TLS / SRTP	TLS / SRTP usage is optional and must be enabled via the PBX configuration; Highly recommended for routing voice traffic through the public internet (WAN)
Supported Codecs	G.711a-law (PCMA), G.711u-law (PCMU)	Offering additional codecs in the SDP may lead to unexpected behavior on codec negotiation and even rejected calls;
TCP Port	5060
UDP Port Range	10000 - 60000

The following settings are strongly recommended to be made on the PBX:

Disable the transmission of the P-Preferred-Identity Header as these may cause problems in call routing through the public switched telephony network
Disable SIP Session Timers as they generate unnecessary traffic and do not provide reliable keep-alive mechanisms