1. Resource Negotiation, Pricing and QoS
for Adaptive Multimedia Applications
Xin Wang
With Henning Schulzrinne
Internet Real -Time Laboratory
Columbia University

2. bandwidth, loss, delay, jitter, availability, price
Today’s IP Networks
Service Level Agreements (SLA) are negotiated based on Application Specific Needs
bandwidth, loss, delay, jitter, availability, price
Application SLA
ISP Networks &
Applications
IP Network
Service
User
Large number of new applications are appearing in the Internet. This includes the real-time audio, video, and mission-critical financial data. This provides ISP more business opportunity, and also challenge.
The value-added services normally require certain service expectations.
Since different applications have different requirements in bandwidth and quality, network resource provision is challenging.
SCOPE
Growth of new IP services and applications with different bandwidth and quality of service requirements
Presents opportunities and challenges for service providers
5/28/2019

3. The needs of Next Generation Service Providers
Revenue from the traditional connectivity services (raw bandwidth) is declining
Increase revenue by offering innovative IP services:
Deliever high-margin, differentiated services
VoIP, VPN, Applications Hosting etc
Gain competitive advantage by deploying new services more quickly, placing a premium on time to market and time to scale
Reduce cost and operation complexity
Evolve from static network management to dynamic service provisioning
Reduce costs by automating network and service management
Service provider needs to provide different premium services, without big cost. The network management and resource provisioning should be automatic and fast.
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4. Internet Structure End User LAN POP NAP Backbone Provider
Regional Provider
Private Network
Backbone
Provider
NAP
LAN
End User
Backbone Provider
POP
Private Peering
Before deciding on the services for the internet, let’s
look at the current Internet situation.
Network is generally divided into different management domains, with direct peering or connect through Network Access Point (NAP).
The Network Access Point (NAP) allows Internet Service Providers (ISPs) to interconnect and exchange information among themselves. The exchanging of Internet traffic is generally referred to as "peering".
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5. NORDUnet Traffic Analysis
Before further describes the service policy, we show some traffic statistics of NORDUnet
NORDUnet interconnects the Nordic national networks for research and education and connects these networks to the rest of the world. The current physical connections are shown on the connectivity map.
NORDUnet provides its services by a combination of leased lines and Internet services provided by other international operators.
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6. NORDUnet Traffic Analysis
Results:
All access links (interconnect ISP’s or connect private networks to ISP’s), including trans-Atlantic links, can get congested.
Average utilization is low: 20-30%
Peak utilization can be high: up to 100%
Congestion Ratio (peak/average): as high as 5.
Peak duration can be very long:
Chicago NAP congested once in 8/00, lasted 7 hours.
TeleGlobe links congested every workday in 8/00 and 9/00
Reasons: Frequent re-configuration and upgrading;Load balancing to protect own users.
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7. Solution - Over-provisioning?
Add enough bandwidth for all applications in access network / backbone
Will over-provisioning be sufficient to avoid congestion?
How much bandwidth is enough to meet diverse user requirements?
No intrinsic upper limit on bandwidth use
How much does it cost to add capacity?
Demand:
Availability of more bandwidth will create its own demand through increasing utilization of bandwidth intensive applications” .real-time audio//video, 3D imaging, virtual reality, etc.
Supply:
Cost of transportation using fiber optics is declining drastically.
However, network management cost: switches and routers, state of the art POP, data centers, etc, will cost money.
QoS: Protect the valuable applications through QoS. But will QoS add big complexity? Providing different servers needs different pricing, otherwise, everyone will ask the best service and end up not services.
Applications do not have the motivation to adapt.
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8. Bandwidth Pricing
Reality: leased bandwidth price has not been dropping consistently and dramatically.
Facts:
300 mile T1 price (rent):
1987: $10,000/month
1992: $4,000/month
1998: $6,000/month (thanks to high Internet demand)
100-mile cabling cost in 1998: $65,000
Links connecting ISP’s are very expensive
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9. Bandwidth Pricing (cont.)
Facts:
International Frame Relay with 256-kbps: thousands dollars a month.
Transit DS-3 link: $50,000/month between carriers.
Transit OC-3 link: $150,000/month between carriers.
Chicago NAP:
$3,900/month/DS-3,
$4,700/month/OC-3.
T megabits per second (24 DS0 lines)
T megabits per second (28 T1s)
OC megabits per second (100 T1s)
OC megabits per second (4 OC3s)
OC gigabits per seconds (4 OC12s)
OC gigabits per second (4 OC48s)
The price for a Chicago NAP connection is distance sensitive and based on the location where the ISP's network meets Ameritech's. ATM pricing also varies with contract length with price deductions for longer term contracts. NAP connection prices start at $3,900 per
month for a DS3 and $4,700 per month for an OC3. Duration of 12, 36 or 60 month terms are available.
Bandwidth may be cheap, but not free
Higher-speed connection -- higher recurring monthly costs.
Option - manage the existing bandwidth better, with a service model which uses bandwidth efficiently.
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10. Solution - Other Service Models
Quality of Service (QoS)
Condition the network to provide predictability to an application even during high user demand
Provide multiple levels of QoS to meet diverse user requirements
How efficient a QoS mechanism manages the bandwidth? How much a user needs to pay for QoS?
Application adaptation
Source rate adaptation based on network conditions can avoid congestion and lead to efficient bandwidth utilization
Why would an application adapt?
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11. A more Efficient Service Model
Dynamic resource negotiation
Network commits resources for short intervals - better response to changes in network conditions and user demand
Usage-,QoS-,demand-sensitive pricing
Allow network to price services based on resources consumed, and allocate resources based on user willingness-to-pay
Give user incentive to select appropriate service based on requirements, adapt demand during network resource scarce in response to price increase
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12. What We Add to Enable This Model?
A dynamic resource negotiation protocol: RNAP
An abstract Resource Negotiation And Pricing protocol
Enables user and network (or two network domains) to dynamically negotiate multiple services with different QoS characteristics
Enables network to formulate and communicate prices and charges
Lightweight and flexible: embedded in other protocols, e.g., RSVP, or implemented independently
Ensures service predictability:commit service and price for an interval
Supports multi-party negotiation: senders, receivers, or both
Reliable and scalable
A demand-sensitive pricing model
Enables differential charging for supporting multiple levels of services; services priced to reflect the cost and long-term user demand
Allows for congestion pricing to motivate user adaptation
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13. What we add... (cont’d)
Demonstrate a complete resource negotiation framework (RNAP, pricing model, user adaptation) on test-bed network
Simulations show significant advantages relative to static resource allocation and fixed pricing:
Much lower service blocking rate under resource contention
Service assurances under large or bursty offered loads, without high provision complexity, or over-provision cost
Higher perceived user benefit and higher network revenue
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