1 / 27

Media Gateway Control Protocol

Media Gateway Control Protocol. Introduction Media gateway Control Interface Entity Naming (Endpoint, Call, Connection, CA) Digit Maps Events Commands Protocol Description Call Flow for RGW to TGW Usage of Commands. Introduction. Components. SS7 Network. Internet. Signaling (SS7)

arista
Download Presentation

Media Gateway Control Protocol

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Media Gateway Control Protocol • Introduction • Media gateway Control Interface • Entity Naming (Endpoint, Call, Connection, CA) • Digit Maps • Events • Commands • Protocol Description • Call Flow for RGW to TGW • Usage of Commands

  2. Introduction • Components SS7 Network Internet Signaling (SS7) Gateway SCP Call Agent SIGTRAN STP MGCP MGCP Residential Gateway Trunking Gateway Residential Gateway Trunking Gateway CO Switch Residential Gateway Trunking Gateway RTP

  3. Introduction • Types of Media Gateway • Trunking Gateway to CO/Switches • Residential Gateway to PSTN Phones • Access Gateway • Business Gateway • Concept of Call Agent • call control intelligent outside gateways • master/slave • undefined CA to CA: maybe H.323, SIP+

  4. Introduction • Relation with H.323 Standards Internet Signaling (SS7) Gateway SS7/ISUP SIGTRAN Gatekeeper Call Agent CO Switch H.225/RAS H.225/Q.931 H.245 Terminal or Gateway MGCP Trunking Gateway RTP

  5. H323, SIP & MGCP • H.323 , SIP • peer-to-peer • internet oriented • intelligent endpoint • optional GK • decentralized • Problems • maintenance • cost & scalability of large systems • signaling & media control are coupled • interoperability with SS7 • MGCP • client-server • traditional telephony • intelligent server • “dumb” terminal • centralized • Concept • gateway decomposed • separate call control from media ports • CA, MG, SG • interoperability with PSTN

  6. Media gateway Control Interface • Endpoints • Types • Digital Channel • Analog line • IVR endpoint • Naming: GW’s Domain Name + Local Name • Local Name • physical interface name / circuit number • e.g., galant.ccl.itri.org.tw/X35V3+A4/15 • Wild-carded • e.g., galant.ccl.itri.org.tw/X35V3+A4/* • e.g., galant.ccl.itri.org.tw/X35V3+A4/$ DS0 endpoint (Channel) Analog endpoint (Connections) (Line) IVR endpoint

  7. Media gateway Control Interface • Calls & Connections & Call Agents • Call Identifier (Call ID) • Created by CA • Unique in the Whole System • Connection ID • Created by GW • Unique under Its GW • Usage of a Connection ID on the same EP • Waiting Period at least 3 minutes • CA Identifier (its domain name) • Redundant CAs : reliability • CA & GW keep “time-to-live” record they read from DNS

  8. Media gateway Control Interface • Digit Map • CA ask GW to collect user dialed digits • Created by CA • Sent to Gateways • Usage • Gateways detect digits, letters, or timer • e.g., (11x|080xxxxxx|03xxxxxxx|002x.T) • Match accumulated digits • under-qualified, do nothing further • matched, send the collected digits to CA • over-qualified, send the digits to CA Inter-digit Timer

  9. Media gateway Control Interface • Events • package name(o) / event name • package: • Generic Media (G) • DTMF (D) • MF (M) • Trunk (T) • Line (L) • Handset (H) • RTP (R) • Network Access Server (N) • Announcement Server (A) • Script Gateway Supported packages Trunk GW (ISUP) Trunk GW (MF) Network Access Server Combined NAS/VOIP GW Access GW (VOIP) Access GW (VOIP + NAS) Residential GW Announcement GW G, D, T, R G, M, D, T, R G, M, T, N G, M, D, T, N, R G, M, D, R G, M, D, N, R G, D, L, R A, R

  10. Media Gateway Control Interface • Commands • 9 commands to handle Connection/Endpoints • EndpointConfiguration (coding charateristics) • NotificationRequest (requested events) • Notify (GW : detected events) • CreateConnection • ModifyConnection • DeleteConnection (GW also) • AuditEndpoint (query status) • AuditConnection (query status) • RestartInProgress (GW : taken in/out of service) • All commands are acknowledged. EPCF RQNT NTFY CRCX MDCX DLCX AUEP AUCX RSIP

  11. Protocol Description • Transactions (simple text format) • command • header • a command line (case insensitive) • Action + TransId + Endpoint + Version • RQNT 1201 endpoint/1@rgw.net MGCP 1.0 • a set of parameter lines • parameter name (upper case): value • X: 0123456789B1 (RequestIdentifier) • R: hd (requestedEvent: hang down) • S: rg (signalRequest: ring tone) • session description

  12. Protocol Description • Transactions • response • header • a response line • Response code + TransId + Commentary • 200 1201 OK • a set of parameter lines (optional) • after CreateCX(/MDCX/DLCX/Audit/Restart) • I: A3C47F21456789F0 (ConnectionId) • session description • Session Description Protocol • separated from header by an empty line

  13. Call Flow for RGW to TGW

  14. Call Flow for RGW to TGW

  15. Call Flow for RGW to TGW • RQNT(1) : NotificationRequest • RQNT 1201 hrd3/15@rgw.whatever.net MGCP 1.0 • N: CA@ca.whatever.net:5678 • X: 0123456789AC • R: hd(E(R(hu(N)),S(dl),D/(D))) • D: (11x|080xxxxxx|57xxxxx|002x.T) • ACK to RQNT(1) • 200 1201 OK N: NotifyEntity X: RequestIdentifier R: RequestEvents D: DigitMap E: Embedded(enable) Request R: Notification Request N: Notify immediately S: Signal Request D: Digit Map

  16. Call Flow for RGW to TGW • NTFY(2) : Notify from RGW • NTFY 2002 hrd3/15@rgw.whatever.net MGCP 1.0 • N: CA@ca.whatever.net:5678 • X: 0123456789AC • O: 5721043 • ACK to NTFY(2) • 200 2002 OK N: NotifyEntity X: RequestIdentifier O: ObservedEvent

  17. Call Flow for RGW to TGW • CRCX(3) : CreateConnection • CRCX 1204 hrd3/15@rgw.whatever.net MGCP 1.0 • C: A3C47F21456789F0 • L: p:10, a: G.711; G.726-32 • M: recvonly • X: 0123456789AD • R: hu • ACK to CRCX(3) • 200 1204 OK • I: FDE234C8 • Session Description • C: CallId • L: LocalCXOptions • p: packetize period(ms) • a: Compression Algo. • M: Mode • X: RequestIdentifier • R: RequestEvents • I: ConnectionId

  18. Call Flow for RGW to TGW • CRCX(4) : CreateConnection • CRCX 1205 card6/5@tgw.whatever.net MGCP 1.0 • C: A3C47F21456789F0 • L: p:10, a: G.711; G.726-32 • M: sendrecv • Session Description from ACK(3) • ACK to CRCX(4) • 200 1205 OK • I: 32F345E2 • Session Description C: CallId M: Mode I: ConnectionId

  19. Call Flow for RGW to TGW • MDCX(5) : ModifyConnection • MDCX 1206 hrd3/15@rgw.whatever.net MGCP 1.0 • C: A3C47F21456789F0 • I: FDE234C8 • M: recvonly • Session Description from ACK(4) • ACK to MDCX(5) • 200 1206 OK C: CallId I: ConnectionId M: Mode

  20. Call Flow for RGW to TGW • RQNT(6) : NotificationRequest • RQNT 1207 hrd3/15@rgw.whatever.net MGCP 1.0 • N: CA@ca.whatever.net:5678 • X: 012345789AE • R: hu • S: v (alerting) • ACK to RQNT(6) • 200 1207 OK N: NotifyEntity X: RequestIdentifier R: RequestEvents S: SignalRequests

  21. Call Flow for RGW to TGW • MDCX(7) : ModifyConnection • MDCX 1209 hrd3/15@rgw.whatever.net MGCP 1.0 • C: A3C47F21456789F0 • I: FDE234C8 • M: sendrecv • X: 012345789AF • R: hu • ACK to MDCX(7) • 200 1209 OK C: CallId I: ConnectionId M: Mode

  22. Call Flow for RGW to TGW • DLCX(8) : DeleteConnection • DLCX 1210 hrd3/15@rgw.whatever.net MGCP 1.0 • C: A3C47F21456789F0 • I: FDE234C8 • ACK to DLCX(8) • 200 1210 OK • P: PS=1245, OS=62345, PR=780, OR=45123, PL=10, JI=27, LA=48 C: CallId I: ConnectionId PS: Packets sent OS: Octets sent PR: Packets received OR: Octets received PL: Packets lost JI: Average Jitter (ms) LA: Average Latency (ms)

  23. Usage of Commands • NotificationRequest() • EndpointId, • [NotifiedEntity,] • [RequestedEvents,] • RequestIdentifier, • [DigitMap,] • [SignalRequests,] • [QuarantineHandling,] • [DetectEvents,] • [encapsulated EndpointConfiguration] Request Notify Request Time Quarantine Period Q T Q: process/discard step/loop (notify) T: events to detect during quarantine

  24. Usage of Commands • CreateConnection() • CallId, • EndpointId, • [NotifiedEntity,] • [LocalConnectionOptiona,] • Mode, • [{RemoteConnectDescptr|SecondEndpointId}] • [EncapsulatedNotificationRequest,] • [encapsulated EndpointConfiguration] Hairpin Connection

  25. Usage of Commands • DeleteConnection() • Delete one connection from Call Agent • ConnectionId in the parameter line • GW : Connection parameters • Multiple connection from Call agent • only EndpontId (and CallId) in the parameter line • GW: No connection parameter • From gateway • Reason-Code & Connection-Parameters in Command

  26. TGW TGW SGW SGW SS7 SS7 PSTN Switch IP Switch IP PBX PSTN Switch MGCP Applications (1) • IP Switch IP Networks Call Agent

  27. TGW TGW SGW SS7 PSTN PBX PSTN PBX IP PBX MGCP Applications (2) • IP PBX IP Networks Call Agent

More Related