Is Your School Ready for An Access Grant? Tommy Whitten & Nathan Curry Madison County Schools Is Your School Ready for An ACCESS Grant? Presented By Tommy

Is Your School Ready for An Access Grant?Tommy Whitten & Nathan Curry

Madison County Schools

Is Your School Ready for An ACCESS Grant?

Presented By

Tommy Whitten, Technology CoordinatorNathan Curry, Network Specialist

With some information lifted from the Alabama Supercomputer Authority’s presentation to the ACCESS Task Force, July 23, 2007

Alabama Educational Technology AssociationFall Symposium 2007

Orange Beach, Alabama



• Video Conferencing Components– H.323 Video– Quality of Service (QoS)– Managed Switch– Firewall– Multipoint Control Unit (MCU)– Network Address Translation (NAT)– Main Distribution Frame (MDF)– Intermediate Distribution Frame (IDF)– Video CODEC



• What is H.323?

– Packet Based Multimedia Communications Systems (IP)

ITU (International Telecommunications Union) standard for videoconferencing over local area networks and packet-switched networks generally. It is based on a recognized real-time standard and is commonly used with video over the Internet to ensure that users can communicate with each other, as long as they are using videoconferencing software which complies with the standard.

The Tandberg and Polycom systems used with ACCESS comply with the H.323 standard for videoconferencing.



• H.323– Uses existing state network infrastructure– Does not require a separate network– Less expensive, more efficient– Network infrastructure is E-rate eligible– Ease of interconnectivity provides growth options– Requires QoS-enabled network for guaranteed

quality



• What is H.320?

– Multimedia over ISDN based networks (IP)– Older standard still used in some VTC solutions– Link used in ISDN are dedicated to VTC. If VTC is not being used, the

bandwidth is not used for other services (i.e.. Internet access)– Since link is dedicated, no need for Quality of Service (QoS)

*All ACCESS labs will be using H.323 standard, but other systems outside of the ACCESS cloud could still use ISDN. Bridging will be necessary when connecting to a system using the H.320 standard.



• What is Quality of Service? (QoS)

– QoS involves prioritization of network traffic on local and across wide area networks. The goal of QoS is to provide guarantees on the ability of a network to deliver predictable results for specific purposes, such as videoconferencing or VOIP. • Bandwidth-how many bits per second are sustained end to

end for each connection• Priority-how many packets will arrive within time specified• Latency-the delay that media packets encounter end to end



• Quality of Service (QoS)– Is enabled using DSCP tagging and CBWFG on routers

and Layer3 switches• Differentiated Services Code Point (DSCP)• Class-Based Weighted Fair Queuing (CBWFG)

– Traffic is classified and tagged at routers based on source/destination IP address

– QoS must be enabled for IVC throughout your school network and the Supercomputer Network.



• The network (inside the school)– Managed Switch

• Capable of individual port configuration• Speed selectable 10/100/1000/Auto*• Duplex selectable Full/Half/Auto*• SNMP capable for monitoring• Supports Telnet, SSH• Vendors include HP, Cisco, 3Com, etc.

• *Always hard code speed and duplex on ports used for VTC• Newer VTC units can be hard coded to 100Mbps full duplex on the

VTC and switch that directly connects to the VTC. If this switch is located in an IDF, then the uplink for the IDF to the MDF should be 100Mbps or higher (hard coded).



• The Network– Firewalls (and NAT)• H.323 uses multiple tcp connections and udp ports

simultaneously for Video Conferencing• The H.323 standard assigns ports dynamically from

1024 to 65535• During call setup, the IP address of the calling party is

sent to the called party in the data field of the IP packet (so NAT cannot translate it)• All firewalls do not support H.323 (e.g. Lightspeed)• Problems may arise when CODEC software is upgraded.



• Multipoint Control Unit (Video Bridge)– Provides a method of connecting 3 or more sites into one

video conference– Allows merging of multiple network types (e.g. – IP and

ISDN)– Maintains a centralized, web-based point of maintenance

for a running video conference– Uses H.231 and H.243 standards

– Video units purchased for ACCESS must be able to connect to at least 3 other sites without requiring the bridge. However, the bridge can connect larger numbers of sites and can also, by acting as a middle-man, combine IP and ISDN calls into one conference (important for virtual field trips).





• The Classroom – Power*

• For IVC cameras/codecs• Monitors• Projectors• Interactive Whiteboards (?)• Document Cameras• VCR/DVD Players• Wireless Access Point• Tablet PC cart (recharging station)

* Power strips/uninterruptible power supplies (UPS) can be used in the VTC lab for conditioned power and to reduce the number of physical outlets needed.



• The Classroom (cont.)

-Network Connections• For Codecs• Printers• Wireless Access Point • Any additional devices that will not use the access

point to connect to the network– Phone/Fax Line• For faxing documents• For troubleshooting help




– Miscellaneous• Tables and chairs

– Keep within the field of view for the cameras – Field of view is 60-70 degrees for Standard Angle lens

(default)– Field of view 80 degrees for Wide Angle Lens– Field of view 90 degrees for HD Lens (Super Wide Angle)

• Projector Mounts– Don’t forget cabling and power in drop ceiling. – Consider the placement of the whiteboard




– Miscellaneous• Sound

– Air conditioning– Busy hallways– Stay away from Ag shops, band/choral rooms, etc.

• Lighting– Room should be well lit– Florescent lighting recommended – Indirect up lighting can diffuse hard direct light and give the

room a more natural look and feel in the VTC session




– Miscellaneous• Wall Colors

– Stay neutral– Gray, Mauve, or Light Blue recommended. – If room is not neutral and needs to be painted, flat satin or

eggshell recommended – Polycom recommends the color “November Skies”

(Benjamin Moore color code # 2128-50)



• IVC Equipment Settings– Hard code speed and duplex settings to match the

settings on the managed switch– Turn OFF encryption– In most situations, turn NAT off on the CODEC

settings. The settings on the CODEC must be compatible with the settings on the Firewall (or NAT device)



• The Intermediate Distribution Frame (IDF)

– Connected to classroom via CAT5/5e/6 cable

– IVC traffic run through a Managed Switch at 10/100Mbps. Duplex setting on port used for IVC must match setting on CODEC

– Recommended – QoS configured on switch ports used for IVC



• The Main Distribution Frame (MDF)

– IDF/MDF backbone cable (Fiber, CAT5/5e/6), 100Mbps, 1Gbps

– MDF Managed Switch, 10/100Mbps. Speed and Duplex settings must match those of IDF.

– Recommended – QoS configured on uplink ports used for IVC



• School Router– QoS capable

• 10 Mbps Fiber connects School Router to District Router

• District Router– QoS capable

• Firewall– People managing the firewall must be in communication with the network

administrator and the CODEC installers.

• Supercomputer Router – QoS capable• 10 Mbps Fiber connects Router to Supercomputer



• What you get from the Alabama Supercomputer?– 10MB fiber connection from your school to the Alabama

Supercomputer Network– AREN is designed to support video through Quality of

Service guarantees.– If both ends of the call are within AREN, ASA can prioritize

the call, resulting in good transmission quality.– Video bridging



• The End

Documents

Is Your School Ready for An Access Grant? Tommy Whitten & Nathan Curry Madison County Schools Is Your School Ready for An ACCESS Grant? Presented By Tommy