OCS 2007 進階系列 – 深入探討 OCS 2007 Mediation Server 及 PSTN Gateways

1. OCS 2007 進階系列–  深入探討OCS 2007 Mediation Server 及PSTN Gateways 馮立偉 台灣微軟特約講師

2. 策略總覽 • The Microsoft® Unified Communications (UC) 目標在於整合豐富, 人員中心導向, 多媒體協同作業以及與交換機 (PSTN) • 需要 SIP-PSTN 介面 • 許多現行 gateway (GW) 解決方案在市面上 • IP Private Branch Exchanges (PBXs) 可與 UC 整合 • UC 架構式設計用來提供 : • 高傳真, 高度安全通訊機制 • 提供一種緊密整合桌上iWorker應用程式, 如 Microsoft® Office Outlook®, Microsoft® SharePoint® 之使用經驗

3. Microsoft 整合通訊架構

4. PSTN 整合要點 • 隨處存取及連接 • UC clients 不管在何位置必須要能存取電話 • 高音訊品質 • 基於 PSTN 及行動網路限制, 此解決方案將提供高傳真音質經驗於所有網路環境中 • 絕佳管理性 • Gateways 將被當成是 UC solution 一部分且管理機制整合於其中. • 音訊品質及可用度分析將被產生以作為除錯, 分析, 及網路最佳化 • 簡單化 • 路由邏輯被內建於 UC 架構中 • 電話機制將會以底下兩種方式呈現給 User s: • A candidate route • Another UC client • Gateways 或PBXs 將提供PSTN protocols 及media 調解工作

5. 現行 PBX 及GWs 問題點 • 缺乏支援 SIP over TCP • Only one GW vendor supports SIP over Transport Layer Security (TLS), which is used in UC to encrypt SIP messages • 沒有支援SRTP • Used in UC to encrypt voice channel • 沒有支援ICE • Used in Microsoft® Office Communicator 2.0 to enable voice to get through firewalls and network address translators (NATs) • 無法與以下互通: • The advanced capabilities of the UC Media Stack • The Windows management scheme

6. Basic GW Appliance Rich GW appliance hosting RTC (compatible) Media Server UC Mediation Server Media GW 配置 • Advanced Media Gateway (MGW) • Rich MGW appliance running media server • UC Mediation Server • UC-compatible media stack • Basic Media GW • Basic MGW appliance with UC Mediation Server

7. Media GWs 種類 • Advanced or basic hybrid GW – 直接與 UC 互通 • Standalone appliance supporting TDM features • Supports SIP over TLS • Supports SRTP • Supports RFC 3261 compliant SIP with Microsoft® Office Live Communication Server protocol extension subset • Including RTC specified call flows • Supports RT Audio and Siren • Supports ICE for FW/NAT traversal • Sends RTCP reports and will respond to reskit troubleshooting probes • Provides remote management capability (Windows® Management Instrumentation?) • Basic GW – SIP/IP telephony GW • Standalone appliance supporting TDM features • Supports SIP over TCP • Supports RFC 3261 compliant SIP • Supports G.711

8. 現行Media GW 合作廠商 Basic hybrid GWs • Dialogic • DMG 4000 • New product to be announced • Based on Windows Server® 2003 • AudioCodes • New product to be announced • Released later in 2007 • Quintum • New product to be announced • Released later in 2007 • Aculabs • New product to be announced • Released later in 2007 Basic GWs • AudioCodes • Mediant 1000 and 2000 • Dialogic • DMG 2000 range • formerly Intel TIMG range • Quintum • TenorDX

9. UC/PBX 種類 • UC enabled • 原生支援與 UC 互通 • UC capable • 軟體升級後變成 UC-Enabled • Non-UC enabled • 無法升級到與 UC 互通性

10. UC/PSTN 整合情境 • Microsoft® Office Communications Server 2007 共存 • UC 使用者仍有 PBX 電話 • 能包含RCC 情境 • Communications Server 2007 standalone • No PBX • 另一種就是 PBX 仍被沒有使用 UCS 的使用者使用

11. Inbound 路由 • 往內電話撥打路由 • 安裝在每一個 FE/SE 伺服器上 • 透過 Communicator 2007 設定 • 提供電話轉接功能 • 即使使用者燈初仍可處理往內呼叫 • 透過 Microsoft® Exchange Server 2007 Unified Messaging and Outlook觸發漏接來電通知

12. 語音郵件路由 • 執行於 Front End 伺服器 • 語音郵件方案是由 unified communications (UC) 與 Exchange Server 2007 Unified Messaging 透過 SIP 整合來提供 • Play on Phone feature from Microsoft® Office Outlook® • Subscriber Access 功能允許透過電話取得語音郵件或 e-mail • 自動總機路由 • 已授權使用者不用再輸入 Pin 碼 Microsoft Confidential - Shared Under NDA

13. Outbound 路由 • 轉換 • 藉由套用區域特定正規劃規則, 轉換撥入號碼為標準格式 • 允許使用者保留現有撥號格式 • 34567 in Cincinatti is actually +1 513 123 4567 • 34567 in Boston is actual +1 617 123 4567 • RNL • Reverse Number Lookup 允許把號碼對應到 URI • Allows users to be called by one name space • E.g. +1 425 123 4567 is actually sip:bob@contoso.com • 路由 • 如果撥打之號碼沒有對應到任何 Microsoft® Office Communications Server 2007 使用者, 則需要往外撥打 • 根據撥打之號碼, 套用撥號授權及選擇合適的 gateway 繞到目的地 Microsoft Confidential - Shared Under NDA

14. Gateway 規劃 Plan A Gateway • Media gateway 用途 • Ubiquitous connectivity • Superior audio quality • Great manageability • Mediation server 功能 • TCP to TLS • Intermediates UC call flows • G.711 to RT Audio and Siren • Apply SRTP to media on UC side • Act as an in-circuit emulation (ICE) client for the MGW • Submit audio quality statistics RTAudio Plan B Gateway G.711 RTAudio Mediation Server Microsoft Confidential - Shared Under NDA

15. demonstration UC 語音呼叫流程

16. Phone Call – You and Me

17. Phone Call – with PBX

18. Phone Call – with Mediation

19. Phone Call – from Anywhere(No Virtual Private Network [VPN] Required)

20. Phone Call – with Gateway

21. Active Directory StandardEdition Simple Deployment, External Access, and Voice(Single Voice Location) Medium business OR Enterprise - small/initial/regional deployment Functionality IM/presence and conferencing External/federation/PIC/anonymous Voice call control and voicemail – single location No high availability A External/ Federated/ Anonymous Users IP-PSTN Gateway Perimeter Network Prereqs Active Directory® directory service, HTTP Reverse Proxy (e.g. ISA) "Plan A" IP-PSTN GW (e.g. Dialogic) Microsoft® Exchange Server 2007 mail environment PSTN Exchange UMServer Scale Edge Server 3 Servers (3 Roles) Few thousand users (goal) Notes Voice location: unique inbound PSTN termination point (e.g. one per area code) Exchange 2007 UM SP1 Beta can not be co-located with Exchange 2007 mailbox Mailboxes may need to scale out independently HTTP Reverse Proxy

22. Active Directory StandardEdition Simple Deployment, External Access, and Voice(Regional Voice Locations with Plan B GWs) Deployment Scenario Medium business OR Enterprise - small/initial/regional deployment External/ Federated/ Anonymous Users Functionality IM/presence and conferencing External/federation/PIC/anonymous Voice call control and voicemail – single location No high availability Perimeter Network Prereqs Active Directory® directory service, HTTP Reverse Proxy (e.g. ISA) "Plan A" IP-PSTN GW (e.g. Dialogic) “Plan B” IP-PSTN GW (e.g. Quintum) Exchange Server 2007 mail environment PSTN Loc 1 Exchange UMServer A B B Edge Server IP-PSTN GW IP-PSTN GW IP-PSTN GW Loc 2 Scale 3 servers plus one Mediation server per Plan B IP-PSTN GW (4 roles) Few thousand users (goal) HTTP Reverse Proxy Loc 3 Notes Mediation server must be located near IP-PSTN GW Mediation Server Mediation Server

23. A IP-PSTN GW 區域性, 多重地點佈署範例 B IP-PSTN GW Mediation Server All other LCS & Ex infrastructure (incl. Perimeter Network) ChicagoHQ B IP-PSTN GW Mediation Server Minneapolis Voice Location 1 (Area Code 612) Cincinnati Voice Location 2 (Area Code 513) Boston Voice Location 3 (Area Code 617) Maps courtesy of www.theodora.com/maps, used with permission.

24. 全球語音部署 Active Directory Primary Perimeter Network Deployment Scenario A/V Conferencing Servers Web Conferencing Servers Global mission-critical enterprise deployment IIS Servers Functionality Geographic deployment Voice call control and voicemail – multiple locations High availability Enterprise Pool: Expanded Prereqs Enterprise Edition Front-End Servers: Expanded Exchange UM Servers Active Directory, HTTP Reverse Proxy (e.g. ISA) "Plan A" IP-PSTN GW (e.g. Dialogic) “Plan B” IP-PSTN GW (e.g. Quintum) Exchange Server 2007 mail environment Active Passive PSTN Region I B B B B A A Loc 1 Enterprise Pool: Consolidated Directors IP-PSTN GW IP-PSTN GW IP-PSTN GW IP-PSTN GW IP-PSTN GW IP-PSTN GW Enterprise Edition Front-End Servers: Consolidated Secondary Perimeter Network Loc 2 Scale PSTN Region II Loc 1 Global Loc 3 Notes Loc 2 Exchange UM scale depends on mailbox locations Loc 3 Mediation Server Mediation Server Mediation Server

25. 全球語音部署 B IP-PSTN GW Mediation Server Oslo Toronto London Paris (EMEA Datacenter) Secondary Perimeter Network Pool #2 Chicago (Global HQ) Primary Perimeter Network Directors Pool #1 Lisbon SFO Tokyo Delhi LAX B B B IP-PSTN GW IP-PSTN GW IP-PSTN GW Mediation Server Mediation Server Mediation Server A A A A A Singapore (APAC Datacenter) Secondary Perimeter Network Pool #3 IP-PSTN GW IP-PSTN GW IP-PSTN GW IP-PSTN GW IP-PSTN GW Sydney

26. Communications Server 2007 Standalone – 往內撥打 • Call routed from PSTN hits Media GW • Media GW converts to SIP call • Communications Server 2007 locates the UC user • Office Communicator rings

27. Communications Server 2007 Standalone – 往外撥打 • Call made from Office Communicator • Possibly to another UC user • Communications Server 2007 routes call to Mediation Server • Mediation Server passes call to Media GW • Media GW places PSTN call

28. Communications Server 2007 Standalone – Call Forward • Call routed from PSTN hits Media GW • Media GW converts to SIP call • Communications Server 2007 forwards call to different UC user • Based on original called-party’s preference • Office Communicator “rings”

29. Communications Server 2007 Standalone – Call Transfer • Office Communicator “rings” – Callee “picks up” • Called party decides to transfer to another UC user • Blind or attended transfer • Caller speaks to new called party

30. Communications Server 2007 Standalone – Conference • UC user decides to escalate two-party call to ad-hoc conference call • Picks conference participants from contact list, based on presence • Conference Server calls out to new participants • Some via PSTN • Original call is transferred to the Conference Server

31. Communications Server 2007 Coexistence Scenario – 往內撥打 • Same as “Standalone” call flow, except: • Call hits PBX, not Media GW • Call is forked by PBX to UC • User decides to pick call up on either UC or phone

32. Communications Server 2007 Coexistence Scenario – 往外撥打 • Same as “Standalone” call flow, except: • Call hits PBX, not Media GW • Call is forked by Communications Server 2007 to PBX • User decides to pick call up on either UC or phone

33. Communications Server 2007 Coexistence Scenario – Call Forward • Same as “Standalone” call flow, except: • Call hits PBX, not Media GW • Call is forked to UC – Communications Server 2007 forwards call • Based on user profile • Deflected user decides to pick call up on either UC or phone

34. Communications Server 2007 Coexistence Scenario – Call Transfer • Same as “Standalone” call flow, except: • Call transfer to second UC user invokes dual fork call to PBX extension • Second UC user picks up on either Office Communicator or phone

35. Communications Server 2007 Coexistence Scenario – Conference • Same as “Standalone” call flow, except: • All UC users have option of taking call on Office Communicator or the phone

36. Communications Server 2007 Coexistence Scenario – 勿打擾 • Call to UC user on DND results in call rejection • Call also rejected on PBX • Caller routed to PBX voice mail

37. UC PBX 合作廠商 • Nortel • Cisco • Avaya • Siemens • Alcatel-Lucent • Ericsson • Mitel • NEC • Nortel is currently testing interoperability • The remainder of these partners are currently working on the interoperability requirements and will be under test before the UC launch • More partners will be announced in due course