SIP FAQs

Here are some frequently asked questions about an SIP (Session Initiation Protocol).

Why chose SIP?

What is a SIP Service Provider?

What is a SIP account and where can I get one?

Does SIP communication work with any Internet Service Provider (ISP)?

What is a SIP capable firewall?

Why do I need a SIP capable firewall?

What is a SIP server?

What is a SIP Gateway?

What is a SIP Phone?

Why chose SIP?

SIP or session initiation protocol is a generic standard that allows for compatibility with other SIP based products offering flexibility and options to create a solutions that caters for your own needs.

What is a SIP Service Provider?

A SIP Service Provider is a company that provides IP communication through the SIP standard, also known as an ISP or an ITSP. Internet Service Providers and IT Service Providers often offer SIP termination and origination services including IP minutes and SIP accounts.

What is a SIP account and where can I get one?

SIP protocol depends on a user name, password and a domain name, very similar to an email address. Each SIP address is generic and allows users worldwide to communicate through voice, data and video, or even instant messaging. SIP address can be purchased from a SIP Service Provider or you can set up your own SIP server.

Does SIP communication work with any Internet Service Provider (ISP)?

Yes, SIP communication is dependent on bandwidth not the provider.

Some ISP's may chose to block SIP traffic, in this instance you will need to contact the provider and ask them to unblock this restriction.

What is a SIP capable firewall?

A SIP capable firewall allows for SIP communication to pass through specific ports whilst still providing security for your network. pbxnsip communicates on SIP port 5060 and SIPS port 5061.

Why do I need a SIP capable firewall?

It is not needed in all cases, it all depends if the provider is using a Session Border Controller. Pure SIP based applications are dependent on full data packets being sent and received, interruptions such as port closures, firewall blocking and NAT can mean that the user experiences poor audio quality and packet loss that can result in call dropping.

What is a SIP server?

pbxnsip is a SIP server. It is the main component of an IP PBX. The SIP server acts as an intermediary between the network and the calls. A SIP server can also be a SIP proxy and/or a Registrar.

What is a SIP Gateway?

A SIP gateway is a term used for a Media gateway used to convert SIP protocol invites and requests to a communication language compatible with legacy phone systems or to deliver traffic to the PSTN.

What is a SIP Phone?

A SIP Phone is a term used for an IP Telephone capable of speaking SIP. Examples are Snom IP Range and Polycom IP Range of telephones.