Codec Tieline ViA User Manual page 161

Advantages and Disadvantages of Using SIP
Advantages of SIP
1. SIP provides interoperability between different brands of codecs due to its standardized
protocols for connecting different devices, e.g. Session Description Protocol (SDP).
2. EBU N/ACIP Tech 3326 provides a minimum set of requirements necessary to ensure
interoperability between equipment intended for the transport of audio over IP networks. It
standardizes the use of ports, encoders, transport protocols and signaling to ensure codecs,
and other SIP-enabled devices like smartphones and VoIP phones, can connect
successfully.
Disadvantages of SIP
1.
SIP requires both codecs to be configured with the same settings before connecting or the
connection will fail. When dialing Tieline to Tieline the dialing codec provides all connection
information to the answering codec.
2.
Not all professional codec manufacturers are fully compliant with all requirements for
interoperability.
3.
SIP connections are more complex to configure.
4.
SIP does not support advanced software enhancements which deliver redundancy and rock
solid reliability over IP, e.g. failover connections, SmartStream PLUS redundant streaming,
Fuse-IP bonding, plus error concealment strategies.
5.
Codecs using SIP cannot use the TieLink Traversal Server for presence and connections. In
addition port forwarding is usually required.
6.
Some ISPs and/or cellular networks may block SIP traffic.
SIP Security
Tools such as Shodan make it easy for anyone to easily locate devices connected to the internet
around the world. Therefore it is critical that security measures are in place for all IP and SIP
connections over the public internet.
Managing Unwanted SIP Calls
Hackers and other nefarious net-bound characters look for networks with easy access in which to
ply their trade. As a starting point they look for networks with open gateways and platforms using
default passwords.
Maintaining Codec Network Security
Adequate security is a major factor in ensuring your codecs and your broadcast network remain
secure. There are several layers of security available in Tieline codecs to maintain secure
connections. These include:
1. Immediately change the default password when you commission and install your codecs
(see instructions which follow). Create a strong password which includes both capital and
lower case letters, symbols and numbers (up to 15 characters can be entered). Password
managers can be useful when managing multiple passwords within organizations.
2. Ensure your codec is behind a firewall and only open the TCP and UDP ports required to
transmit session and audio data between your codecs. Using non-standard ports instead of
Tieline default ports can also ensure the codec is more difficult to discover by external
parties.
3. Ports 80 and 8080 are commonly used to access the Tieline codec web server. You can add
an additional layer of security by translating these ports on the WAN side of your network
© Tieline Research Pty. Ltd. 2020
This is not possible when using SDP in SIP mode.
ViA User Manual v3 161