VoIP review
What is VoIP? Brief review of IP, Brief review of telephones and voice. RTP, payload type, RTP timestamps, RTCP, mixers and translators.
Hands on Softphone configuration, analysing RTP packets.
What is SIP?
Why SIP? SIP history, SIP standards, SIP protocol stack, SIP relationship with other protocols, SIP functions, SIP capabilities, initial SIP phone startup, how SIP works, and a basic SIP call.
Hands on Peer to peer SIP. Video calls.
SIP messages
SIP sessions, SIP flows, Message structure, Core SIP methods: INVITE, ACK, BYE, CANCEL, OPTIONS, REGISTER. Extension methods. Response codes. SIP call flows. INVITE message format, SDP in the SIP INVITE.
Hands on Setting up a PBX, analysing SIP packets.
SIP and Wireshark
Capturing packets, display and capture filters for voice, statistics, telephony menu, SIP statistics, call flows, RTP stream analysis.
Hands on Analysing VoIP calls.
SIP architectures
UA client, UA server, Proxy servers, registration, Redirect servers, registrars. SIP phones, gateways, application servers, and other products. Stateful and stateless servers. Various call scenarios.
Hands on SIP proxies. SIP trunks.
SIP addressing
URLs, SIP addresses, registration, Location and Directory servers. Address tracking.
Hands on SIP and DNS.
Supplementary services
SIP signalling, call hold, call transfer, call forwarding, conferences, call control. SUBSCRIBE, NOTIFY, MESSAGE, PRACK.
Hands on Analysing SIP supplementary services.
SIP security
SIPS, SRTP. UAC authentication, VPN, firewalls, NAT problems and SIP. Solving NAT traversal issues, STUN, TURN, ICE Session Border Controllers.
Hands on SIP authentication.
SIP and the PSTN
Inter working with PSTN, ISUP to SIP mapping, SIP-T, SIP and SIGTRAN.
Hands on SIP gateways and trunks.