Transcript compare ss7 and sip based signaling

MULOT Florence
STEMMER Séverine
SUJET 1
COMPARE SS7 AND SIP
BASED SIGNALING
THE SUBJECT
COMPARE SS7 AND SIP BASED SIGNALING :
Make a presentation (Power Point) which will compare SS7 and DSS1 with SIP
or H.232 signaling. Use Internet, earlier presentation on www.comtel.cz, other
relevant materials. Focus on using SIP or H.232 to provide telco services (voice
calling with other supplementary services like CLIP, CLIR, CW, CFU, CFNR,
CFBU, HOLD,...). Discuss differences and and mature of IP based signaling.
SUMMARY
 Research
 What is Signaling
 SS7 : Signaling System
 SIP : Session Initiation Protocol
 H.323
 DSS1
 Difficulties
 What we have learnt
RESEARCH
First, we used Internet to define the different words of the subject
English websites
We found different sources that we mixed together
WHAT IS SIGNALING ?
As users of the PSTN (Public Switched Telephone Network), we exchange
signaling with network elements all the time.
Examples of signaling between a telephone user and the telephone network
include : dialing digits, providing dial tone, accessing a voice mailbox, sending a
call-waiting tone, dialing *66 (to retry a busy number), …
SS7 : SIGNALING SYTEM
DEFINITION
Signaling System #7 (SS7) is a set of telephony signaling protocols which are
used to set up the vast majority of the world's PSTN (Public Switched Telephone
Network) telephone calls.
It is usually abbreviated to SS7 while in North America it is often referred to as
CCS7, acronym for "Common Channel Signaling System 7". In some European
countries, specifically the United Kingdom, it is sometimes called C7 (CCITT
number 7) and is also known as number 7 and CCIS7.
USES OF SS7
SS7 provides a universal structure for telephony network signaling, messaging,
interfacing and network maintenance. It deals with establishment of a call,
exchanging user information, call routing, different billing structures, and supports
Intelligent network (IN) services.
SS7 is also important in linking VoIP traffic to the PSTN network.
SS7 is also used in the mobile cellular telephony networks like GSM and UMTS
for voice (Circuit Switched) and data (Packet Switched) applications.
SIP : SESSION INITIATION PROTOCOL
DEFINITION
Session Initiation Protocol is a network communications protocol commonly
employed for Voice over IP (VoIP) signaling. In VoIP networking, SIP is an
alternative approach to signaling using the H.323 protocol standards.
SIP is designed to support the calling features of traditional telephone systems.
SIP is a peer-to-peer protocol. SIP is also a general-purpose protocol for
multimedia communications not limited to voice applications.
COMMERCIAL APPLICATION
The Real-Time Transport Protocol (RTP) used to carry the media stream does not
traverse NAT routers. Most SIP clients can use STUN to traverse full cone,
restricted cone, and port restricted cone NAT but not symmetrical NAT. Also some
newer routers now recognize and pass SIP traffic. RTP Proxies, special purpose
SIP line speed processors analogous to HTTP proxies commonly used in the
early 1990s, enable CALEA and traversal of older, SIP-unaware NAT devices.
H.323
DEFINITION
H.323 is a protocol standard for multimedia communications. H.323 was designed
to support real-time transfer of audio and video data over packet networks like IP.
The standard involves several different protocols covering specific aspects of
Internet telephony. The International Telecommunication Union (ITU-T) maintains
H.323 and these related standards.
Most voice over IP (VoIP) applications utilize H.323. H.323 supports call setup,
teardown and forwarding/transfer. Architectural elements of a H.323 based
system are Terminals, Multipoint Control Units (MCUs), Gateways, an optional
Gatekeeper and Border Elements. Different functions of H.323 run over either
TCP or UDP.
DSS1
DEFINITION
Digital Subscriber Signalling System No. 1 (DSS1), also known as Euro-ISDN or
E-DSS1 (European DSS1), is a digital signaling protocol (D channel protocol)
used for the ISDN. The interface is also called NET3 for BRI and NET5 for PRI
lines. Can also be called CTR4.
DSS1 is a pan-European standard developed by ETSI. In 1989, 26 network
operators from 20 European countries decided to develop this standard to replace
earlier national protocols (such as FTZ 1 TR 6 or VN3). DSS1 has been one of
the keys to the success of the ISDN within European countries (as compared to,
for example, the U.S.).
Non-European countries using DSS1 include Australia, Brazil, India, Israël, New
Zealand, Pakistan, Peru, Singapore, Taïwan and the United Arab Emirates.
DIFICULTIES
 All documents were in English, so it was difficult to understand some words
 The subject was really vague and a little unclear for us
 We don’t know if we had to study H232 ou H323
WHAT WE HAVE LEARNT
 General ideas about Telecom
 Notion about networks
 We have learnt different protocol