Transcript Session Title - Blackboard Inc.

Basics of Communications
Presented By Patrick Bolwahnn
April 14, 2005
Today…
• Session Objectives
– Learning and Understanding the Basics of Reader
Communication
• Innovation
– Terminology
– Infrastructure Considerations
– Equipment and Devices
• Results
– The ability to understand and deploy a well
designed reader network.
WT Background:
•
•
•
•
Installed January 1998
Wired February 1998
Recarded Fall of 1998
Services Offered
– Copy, Laundry, Vending, Bookstore
– Point of Sale, Activity Validation
– 120 Locations
WT Background:
• FY 2003-2004
– 9000 Active Cardholders
– $1.5 Million in Deposits
• Meal Plans – 300k
• Book Loans – 350k
• Flexible Spending – 850K
– 220 On-Campus Locations and 35 OffCampus Locations
– Door Access
Terminology:
• Network Processor - Transaction Approval
• Application Processor - Long Term Storage, DB
• Reader Networks – Communications Devices,
Wiring and Readers
• Locations - Location Number a Reader is Assigned
• Loop - Physical Wire
• Addresses - numbers 0-15 assigned to reader
Terminology:
• Modems – communication device (RS232)
• Converters – Converts from one protocol to another.
• IP Communications – Communicating over a Data
Network
• RS232
• RS485
Terminology
:
• Do you have to be a wiring
expert?
•No
Just need to know enough to make good decisions
Installation Considerations:
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•
•
AP/NP Location
Number & Size of Buildings
Number Readers in each building
Cable topology – fiber, copper
Network Strategy and Support
– Data Network
– Separate Reader Network / VLAN
• Power connections
• Shelf/rack space
WTAMU Communications:
• Remote Line Driver loops
• IPC loops
– 1 IPC Loops
• 25 Active Loops
– 24 Remotes Loop
– 2 RF Loops
• 265 Locations
Reader Networks:
• Consists of
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–
–
–
Network Processor
Communications Devices
Cabling
Readers
• Cabling and Communication Devices make
up the three basic reader loops
– Local
– Remote
– IP Network
Network Processor:
• Network Processors communicates with each
reader on the
network and processes
their transactions.
• NP’s Communication
is handled through
– CP16 Panels
– Mux Panel
– LAN Cards
Local Loops:
• Local loops are generally within the same
building as the NP. Local loops can be
accomplished two ways.
– Use CP8 boards which have some RS-485
converters built in.
– CP16 boards do not have converters
– NP cable to RS 485 converter
Reader
NP
485
Reader
Remote loops:
• A Remote Loop is any loop that services a
remote building(s) or remote campuses. This
can be accomplished through many
combinations of devices.
– Devices Types
•
•
•
•
•
Terminal Servers(TS) via a Data Network or Internet
Line Drivers
RS 485 converters.
IP Converters
IP Readers
Communications Protocols:
• Protocols are like different languages. Some
protocols the BTSUE system uses to
communicate are:
– RS 485
• Allows multiple units to communicate over the same wire. ( 5
pin)
– RS 232
• Basic data communication used in PC and device
communication, 1 – 1 ( 3 pin)
– TCP/IP
•
Standard Networking protocol which Terminal servers, IP
Converters, & IP readers utilize on a data network.
Standard Communications:
• Line Drivers
– Short haul modems = less than 2 miles
– Long distance modems = more than 2 miles
– Types of medium
• Fiber
• Copper
– Uses Standard RS 232
protocol (3 pin)
Standard Communications:
• Special devices
– Multiplexer
– Loop Splitters
Standard Communications:
• RS 485 Converters
– Design to convert RS 232 to 485 protocol
– Has 1x10 jack to
connect local reader
cable network
Standard Communications:
Building A
Computer Center
NP
Loop
Spliter
Line Driver
Line Driver
485 Reader
Line Driver
Building B
Line Driver
Line Driver
Building C
Line Driver
IP Communications:
• Terminal Servers
– Designed to Convert RS232 to TCP/IP and
back again.
• IP Converters
– Design to convert TCP/IP to RS 485
protocol
• IP enabled Readers VR/MDB2
IP Communications:
First IP Communications devices were terminal servers
NP
Terminal
Server
Data Network
Terminal
Server
RS 485
Reader
IP Communications:
• IP Converters
– Design to convert TCP/IP to RS 485
protocol
IP Communications:
NP
Data Network
IP Converter
IP
Reader
RS 485
Reader
Other Communication Methods:
• Radio Frequency
– Blackbox RF-115 modem
– 900 Mhz RS232 protocol
– Range up to 20 miles
with repeaters
Wiring:
• Supported wiring
– Belden 8723
• 2 pair with shield
• Use T568b wall plate with screw lugs
or DB 15
– Cat 5 10base-T (most common installation)
• Twisted Pair Network Cabling
• Use T568b RJ45 standard network jack
Pros for communication types:
Local Loops
Lower cost – no
LD or TS.
-Fast response
times.
-Independent
wiring – not
attached to net.
Line Driver
-Fast Response times.
-Independent wiring - not
attached to data network.
-Slightly Cheaper than TS.
-Supported by Blackboard
-Simple - No Configuration
needed
Always up!
-Works with Copper and
Fiber lines
-Easy to troubleshoot
IP
- easiest/quickest to
install, or move
-Easy to diagnose
communication
problems???
-Comes back on-line
fairly quickly, when the
network is out
-Could be used over the
Internet to connect
remote campuses
Cons for communication types:
Local Loops
-Difficult to move
server.
Line Driver
-Difficult to move
server.
IP
-Network Outage
-Denial of Service
-Copper needs optical
isolation
- Cost of running
wiring if not available
-Firewall and VLAN’s can
block communication if not
configured right.
-Depends highly on relationship with IT
Security Issues with IPC:
• IPC’s Communicate with the NP with
128bit Blowfish encryption.
• No problems so far with denial of
service attacks.
• Downstream communication between
IPC and Reader is still vulnerable.
• Having the IPC on a VLAN and behind
a firewall greatly increases security.
Recap:
• Installation Considerations
–
–
–
–
–
AP/NP Location
Number & Size of Buildings
Number Readers in each building
Cable topology – fiber, copper
Network Strategy and Support
• Data Network
• Separate Reader Network / VLAN
– Power connections
– Shelf/rack space
• Links
– Behind the Blackboard
• System Implementation Guide
http://www.blackboard.com/docs//h931431.pdf
• Follow up Contact Information
[email protected]
• If you remember one thing…
There are many options for deploying
your reader network