General SIP information

SIP addresses

DIDWW originates calls to customers from the following endpoints:

  • - New York PoP

  • - Frankfurt PoP

  • - Los Angeles PoP

  • - Miami PoP

  • - Singapore PoP

These IP addresses correspond to our routing cluster exit nodes. For UDP transport we send signaling from port 5060. For TCP we use port range from 5070 to 5200

RTP addresses

Our system sends RTP packets from the following subnets:


with RTP port-range: 1024-65535


We transmit and receive RTCP packets from port = rtp_port + 1 (as recommended in RFC3550). Additionally, we are able to receive RTCP packets on the same port as RTP, considering utilizing RTCP conflicts avoidance payloads (payload types 72-76).


Our systems supports TLS as a secure transport for SIP signaling and SRTP as a media encryption mechanism. All three SRTP key negotiation mechanisms are supported - SDES, DTLS and ZRTP.


The SRTP media encryption and TLS SIP transport are disabled by default. Please contact our sales team to allow traffic encryption for your account.

Supported codecs

  • G.711 A-law/U-law

  • G.729

  • G.723.1

  • L16

  • G.726-16/G.726-40/G.726-32/G.726-24

  • G.721

  • GSM

  • Speex

DTMF transport methods

DTMF signaling is supported as follows:

By default RFC 2833 enabled