BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
On the Optimal Configuration of Metro Ethernet for Triple Play
András Kern, Tibor Cinkler, István Moldován
2nd EuroNGI Conference on Next Generation Internet Design and Engineering, Valencia, SPAIN 2
BME - TMIT BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
Triple-Play in Metro Ethernet Network
Data
TV + Set Top Box Home Gateway
Video
Head End
VoD
VoIP
GW
Access Node
Switch
Switch
Switch
SwitchEdge node
Edge node
Service Providers’ NetworksMetropolitan NetworkLocal Access / First mileCustomers’ Home Net.
» Three different services on a single infrastructure» High Speed Internet (HSI)» Voice over IP (VoIP)» Video service (IPTV, iVoD)
2nd EuroNGI Conference on Next Generation Internet Design and Engineering, Valencia, SPAIN 3
BME - TMIT BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
» Ethernet is the most dominating LAN technology» Cheap equipment + high speed (up to 10 Gbps)
Ethernet in Metro Networks
Switch Edge nodeAccess Multiplexer Switch SwitchSwitch
Metro Core
RS CS TR RD TD CDTALK / DATA
TALK
CableModem1 2 3
4 5 6
7 8 9
* 8 #
Metro Access
First MileHome Network CoreMetro Network
» Introduce Ethernet into the Metro network (Metro Ethernet Forum): » consistent network platform
» Ethernet should be Carrier Grade:» Traffic and User separationTraffic and User separation ~ Virtual LANs» QoSQoS ~ 8 traffic classes » ReliabilityReliability ~ Rapid Spanning Tree Protocol» ScalabilityScalability ~ MAC-in-MAC and Q-in-Q» Operation, Administration ManagementOperation, Administration Management
2nd EuroNGI Conference on Next Generation Internet Design and Engineering, Valencia, SPAIN 4
BME - TMIT BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
Routing in Ethernet: Spanning Trees Protocols (STP)
» MORE VLAN based spanning trees» Multiple spanning tree
instances» Each tree runs a separate
Rapid STP instance» 1 VLAN 1 tree
Bridge D
Bridge A
Bridge B
Bridge
Bridge
Bridge
Bridge
Bridge
Bridge C
Root II.Root I.
» By default tree spanning is “Topology-Driven”:» Port costs based on topology and link capacities
» Costs can be set manually (to obtain desired trees)
» Spanning Trees form loop-free logical topologies » Their shape influenced by Port Costs» Provide restoration
2nd EuroNGI Conference on Next Generation Internet Design and Engineering, Valencia, SPAIN 5
BME - TMIT BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
Resource Management Architecture
» TE-pipe» Runs between access and
edge nodes» pre-provisioned resources» Per Service
» AN & EN» Enforcing traffic via
» Policing » Shaping
» Network Management Entity» Manages the resources» Performs CAC based on
service datas and QoS.» Configures network elements
(e.g., SNMP)
Switch
Switch
SwitchModem
Modem
Switch
Switch
Switch
Network Management Entity
Computer
Telephone
TV and Set Top Box
Access Node
Access Node
TE pipe
Edge node
Edge node
2nd EuroNGI Conference on Next Generation Internet Design and Engineering, Valencia, SPAIN 6
BME - TMIT BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
QoS Model
» Priority based scheduling:» Lower priority traffic is not served until there is higher priority traffic
in the queue.
» To ensure low delay for each QoS class:amount of higher priority traffic should be limited for each link
» Static global limits are defined for each class
» The method of how to determine these limits is out of scope.
Class ID Provided service
BW ratio
1 VoIP 0.1
2 IPTV 0.2
3 - -
4 HSI remaining
2nd EuroNGI Conference on Next Generation Internet Design and Engineering, Valencia, SPAIN 7
BME - TMIT BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
IPTV: Multicast in Metro Ethernet
» Efficient distribution of Video needs multicast
» Dynamic Multicast» Ethernet switches “snoops” IGMP messages» Decides on which ports sends the packet out.
» Manual Filtering» VLAN are for restricting Broadcast Domains» Shaping the VLAN to Multicast-trees
» Assumed method» Forming P2MP Pipes ~ VLANs» Carrying more MC tree» IGMP snooping can be also used
2nd EuroNGI Conference on Next Generation Internet Design and Engineering, Valencia, SPAIN 8
BME - TMIT BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
HSI: Statistical Multiplexing
» Traffic of individual users highly varies» Considering it at PIPE dimensioning
» Aggregation of these flows still fluctuates
» Guèrin's model assumed» Variances of Flows have
to be estimated» Flows ~ Independents & Normal Distribution
» TE pipes are described: (Mean Rate; Peak Rate)
n
i
n
iiiaggr mBW
1 1
2
BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
On the Optimal Configuration of Metro Ethernet for Triple Play
Proposed Method and Simulation Results
2nd EuroNGI Conference on Next Generation Internet Design and Engineering, Valencia, SPAIN 10
BME - TMIT BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
Problem Formulation
» Input parameters:» Topology » QoS model» Static Traffic Matrices for each service» Tree Instances
» The proposed method» Defines uni/multicast pipes for demands,» Spans the tree instances and» Assign the pipes for the tree instances
» Integer Linear Model was presented for the basic problem, but it does not deals with» statistical multiplexing» multicasting
2nd EuroNGI Conference on Next Generation Internet Design and Engineering, Valencia, SPAIN 11
BME - TMIT BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
Proposed Heuristic Method
» Decomposes the problem to
» Sequential allocation of pipes AND appending them to a tree instances.
» Demand ordering problem
» In each iteration random selection between:» Allocation of NEW pipe» Remove an existing tree
2nd EuroNGI Conference on Next Generation Internet Design and Engineering, Valencia, SPAIN 12
BME - TMIT BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
Case Study» Assumed dual homing based topology
» Services» VoIP
» Unicast + symmetric PIPEs» No statistical mux assumed.» 10% of total traffic
» Video» Multicast + asymmetric PIPEs» Medium traffic variance (PMR ~1.2)» 30% of total traffic
» HSI» Unicast + asymmetric PIPEs» Large traffic variance (PMR ~ 2.0)» 60% of total traffic
2nd EuroNGI Conference on Next Generation Internet Design and Engineering, Valencia, SPAIN 13
BME - TMIT BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
Traffic Model
» Demand sizes based on Gaussian distribution» PEAK rate: Total traffic level x Service Ratio » MEAN rate: PEAK rate / PMR
» VoIP and HSI : separate PIPEs for each AN—EN pair
» IPTV: 1 multicast PIPE for each EN.
» Performance descriptor: ACHIEVABLE THROUGHPUT» Determined via binary search of Total traffic level
2nd EuroNGI Conference on Next Generation Internet Design and Engineering, Valencia, SPAIN 14
BME - TMIT BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
The effects of Statistic Multiplexing
Same throughput –
less resources
20% more throughput achieved
2nd EuroNGI Conference on Next Generation Internet Design and Engineering, Valencia, SPAIN 15
BME - TMIT BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
Notes on scalability
» „OFF-LINE” configuration method» No strict time constraints
» Scalability still important» On larger networks » Perform Dynamic TE
» The proposed method iterative + polynomial steps» Finds solutions within a minutewithin a minute in the Test Case» Needs 100 rounds to find the solutions
» For 1000 and 10000 rounds only a slight increase of performance…
» Recent simulation on larger networks also show its scalability
2nd EuroNGI Conference on Next Generation Internet Design and Engineering, Valencia, SPAIN 16
BME - TMIT BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICSDEPARTMENT OF TELECOMMUNICATIONS AND MEDIA INFORMATICS
Conclusion
» To provide Triple-Play QoS aware architecture is needed
» To decrease costs Ethernet is a good choice
» We propose» An efficient algorithm for off-line configuration» Deals with priority based QoS» Multicast» Exploit the effects of Statistical Multiplexing
» Its performance is presented on a test case