1.
[ S N O M 4 S N A T F I L T E R ]
1.1 Applications
The filter can be used in the following scenarios:
•Corporations. Corporations which operate their infrastructure be- hind NAT and/or firewalls can talk to the public Internet through the filter.
•Operators. Operators offer the NAT traversal feature to their cus- tomers. Using the scalability feature of the filter, the operation of large networks becomes possible.
•Record specific calls for legal purposes. In many countries, opera- tors must provide the possibility to record certain calls on request. The filter can perform this task.
•Recording can be used for legal proofing (brokers, etc). The filter is fully compliant with other SIP equipment and can, for example, put between a PSTN gateway and SIP phones.
1.2 Features
The filter offers powerful features based on modern VoIP technol-
ogy:
•The
•A
•Support for instant messaging, presence and all other
•Rich logging features allow easy maintenance.
•Recording functions based on number lists and expressions offer a flexible way of filtering out information.
•Recordings can be saved in WAV file format (the data rate is 6 MB per hour).
•Almost stateless operation allows the filter to be used in server farms. This offers a tremendous scalability and redundancy making the product suitable for large operators.
6 • Overview