Session Intiation Protocol (SIP)
- It supports voice calls, video conferencing, instant messaging, and media distribution.
- Transport over TCP and UDP, Port 5060 and 5061
- TCP/IP Model - Application Layer Protocol
- Predominantly used for Voice Over IP(VoIP) Networks
- When a user places a call from their device, SIP initiates the call with a server. The communication data is sent through the trunk through the organization’s communication network or a PSTN, routing the communication data to its destination. When either user ends the call, SIP terminates the connection on the network.
Example) basic call flow
Advantages of SIP
- Cost Effective
- Increased Flexibility
- Supports Multimedia
- Easy Setup
- Low Maintenance
Challenges and Limitations of SIP
- Requires sufficient bandwidth - For Real-Time media communication such as VoIP calls, video meetings, data flow between all users, no of sip channels(concurrent calls)
- SIP trunking and onsite PBX require maintenance
- Security vulnerabilities