data centers and ip pbxs lan structures private clouds ip pbx architecture ip pbx hosting
TRANSCRIPT
Data Centers and IP PBXs
LAN StructuresPrivate Clouds
IP PBX ArchitectureIP PBX Hosting
Local Area Networks(LANs) at
Enterprises• Characteristics
– Ownership– Limited geography– High speeds– Shared devices
• Ethernet & TCP/IP
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
LAN architecture
Architecture: how devices fit together in a network.
Data Centers
Purpose of a data centerEnvironmental considerations
Cooling HeatingFloodingSecure access
Space issuesNot too large – space costs $Not too Small– need to grow
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
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 site Remote, backup site
Physical host server withvirtual machines
SAN*
SAN*
**Wide Area Network
Switch
WAN**
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
Wide area network
Centralized voice mail/unified communications server
Voice over IP system in box
Layer 2 switchCommunications server
Headquarters
Remote office
Gateway
Router
Router
PSTN: Public switchedTelephone network
A VoIP Telephone System VoIP Architecture
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
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?
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
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 PublicInternet
VoIP Links
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?
Summary
• LAN architecture– Backbone
• Private clouds• Structure of VoIP telephone systems• Hosted IP telephone systems• VLANs (virtual local area networks) & Storage
Area Networks