1. Data Centers and IP PBXs LAN Structures Private Clouds IP PBX Architecture IP PBX Hosting

2. Local Area Networks (LANs) at Enterprises Characteristics – Ownership – Limited geography – High speeds – Shared devices Ethernet & TCP/IP

3. Facts about LANs Local in nature LAN mostly covers a small area Router ensures you reach outside network LAN interconnects computers LANs can be 100 MB or higher Economical way to share printers LANs can be wireless LAN uses file server for network operating system LANs have switches to connect devices together LANs segments can be connected by fiber optic cabling Can access LANs with a password Wi-Fi routers support multiple protocols LAN switches reduce cost of cabling devices together If main file server gets corrupted all LAN devices can be infected LANs enable students to share applications LANs can connect to alarm systems LANs use Ethernet protocols Wi-Fi eliminates cost of wiring to devices

4. LAN architecture Architecture: how devices fit together in a network.

5. Data Centers Purpose of a data center Environmental considerations Cooling Heating Flooding Secure access Space issues Not too large – space costs $ Not too Small– need to grow

6. Private Clouds Created within organizations Emulate cloud providers’ data center structures – Centralized applications – Standardized applications – Self service Take steps to achieve greater efficiencies If at provider; dedicate server to single customer; costly

7. Automatic Failover (backup) to a Remote Site Using Replication Software in Virtualized servers Physical host servers Ethernet LAN *Storage area network Ethernet LAN Redundant Switches Servers at headquarters with replication software and virtual machines Headquarters siteRemote, backup site Physical host server with virtual machines SAN* **Wide Area Network Switch WAN**

8. Virtual LANs virtual local area networks (VLANs) –“Tagged” as a separate LAN in software –Packets in VLANs prioritized for better voice quality and multi-media services –Only certain packets reach them –Shielded from some viruses

9. Wide area network Centralized voice mail/unified communications server Voice over IP system in box Layer 2 switch Communications server Headquarters Remote office Gateway Router PSTN: Public switched Telephone network A VoIP Telephone System VoIP Architecture

10. What do you know about IP PBXs Changes can be made in software much easier than traditional TDM systems Phone calls transmitted over the internal IP network Media gateway has digital signal processor to compress voice Can connect to PSTN (traditional networks) and Internet (IP) networks Have built in applications like voice mail Can transfer voice/video over network Can contain unified communications email box w/voice mail messages; one software application also video Can integrate w/some mobile phones Can easily add more phones/auto attendants/applications Because it’s digital/ can store more data/ recorded calls Easier to manage

11. Steps in VoIP PBX Selection How do you determine the organizations’ needs? – Size of org. in number of people – Number of sites; – Requirements for conference calls – may need more phone lines – Employee functions – does each staff need a phone? – Look at employee usage – phone bill $s; # of calls – Call center needs? – customer support – Budget; security needs – infrastructure – Growth? Financial officer, CEO What are the 5 most important criteria for system selection? – Cost, User friendliness; reliability, security; size & energy needs What questions will you ask vendors in order to evaluate them? – What is the difference with competitors; references; service; do they offer more equipment; maintenance? Specifications of what’s included in contract & maintenance contract; what’s included; # of phones, capacity without a processor; cost?; redundancy? Global reach?

12. The Rationale for IP PBXs VoIP advantages –Open standards Applications for call centers, voice mail etc. Telephone compatibilities –Voice and data on interoffice trunks –Centralized Administration –Centralized Unified Communications

13. Hosted IP Telephone Systems - Rationale Rationale –Lack of in-house expertise –Uncertain growth –Dispersed sites Media server, gateway and software at provider Web interface for customer programming Provider with VoIP hardware & software Private or Public Internet VoIP Links

14. Should our Organization Use a Hosted IP PBX? Absolutely We don’t want to do maintenance Just one Ethernet network We have a positive vision of technology Easier for vendor not us to update Save $ on staff Upgrades by host More skills at host For small companies, hosted IP has more services Save on energy Not stuck with capital for expensive equipment – more flexible Never! Like current system, More $ monthly Others will look down on company image poor Security worries Want to control system Tech. too new If telephone line is cut no service Not supported in enough countries Our intellectual property not secure over Internet What happens if host goes out of business?

15. Summary LAN architecture – Backbone Private clouds Structure of VoIP telephone systems Hosted IP telephone systems VLANs (virtual local area networks) & Storage Area Networks