comparison of or and mdr overhead and delivery ratios
DESCRIPTION
Comparison of OR and MDR Overhead and Delivery Ratios. Stan Ratliff Cisco Systems. Description of Flooding Algorithms. Overlapping Relays (OR) Described in draft-chandra-ospf-manet-ext-03 Based on Multipoint Relay (MPR) flooding algorithm in OLSR MANET Designated Router (MDR) - PowerPoint PPT PresentationTRANSCRIPT
Comparison of OR and MDR Overhead and Delivery
Ratios
Stan Ratliff
Cisco Systems
Description of Flooding Algorithms
• Overlapping Relays (OR)– Described in draft-chandra-ospf-manet-ext-03– Based on Multipoint Relay (MPR) flooding
algorithm in OLSR
• MANET Designated Router (MDR)– Described in
draft-ogier-manet-ospf-extension-05
Changes to OR algorithm
• Added functionality described in draft-roy-ospf-smart-peering-00
• If new neighbor already in SPT, mark neighbor as FULL with respect to link advertisement.
• Defer DB synchronization until necessary.
Changes to Smart Peering
• Added functionality to smart peering– Missed deadline for posting new draft for this
IETF; posting to come.
• Additions are referred to as Unsynchronized Adjacencies
Unsynchronized Adjacencies• After new neighbor found in SPT and DB
sync deferred,
• Link to new neighbor marked as Unsynchronized (New ‘U’ Bit) in LSA
• A “special” SPT is created, ignoring links with U-bit set.
• This new SPT is consulted to determine whether DB synchronization is required, and is updated for all link state changes.
Other Changes from DT deliverable
• Velocity was increased to 16 meters/sec.
• Pause Time was decreased to 1.
• ACK Cache timeout was increased from dead interval (6 sec) to 100 seconds
• Multiple simulations were run, varying radio range from 100 meters to 200 meters in 20 meter increments.
20 Node OSPF Overhead
0
10
20
30
40
50
60
70
80
100 120 140 160 180 200
Radio Range in Meters
KB
PS OR+Smart Peering
MDR Bi-Connected
20 Node Delivery Ratio
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
100 120 140 160 180 200
Radio Range in Meters
Del
iver
y R
atio
OR+Smart Peering
MDR Bi-Connected
30 Node OSPF Overhead
0
50
100
150
200
250
100 120 140 160 180 200
Radio Range in Meters
KB
PS OR+Smart Peering
MDR Bi-Connected
30 Node Delivery Ratio
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
100 120 140 160 180 200
Radio Range in Meters
Del
iver
y R
atio
OR+Smart Peering
MDR Bi-Connected
40 Node OSPF Overhead
0
50
100
150
200
250
300
350
400
450
100 120 140 160 180 200
Radio Range in Meters
KB
PS OR+Smart Peering
MDR Bi-Connected
40 Node Delivery Ratio
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
100 120 140 160 180 200
Radio Range in Meters
Del
iver
y R
atio
OR+Smart Peering
MDR Bi-Connected
50 Node OSPF Overhead
0
100
200
300
400
500
600
700
800
100 120 140 160 180 200
Radio Range in Meters
KP
BS OR+Smart Peering
MDR Bi-Connected
50 Node Delivery Ratio
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
100 120 140 160 180 200
Radio Range in Meters
Del
iver
y R
atio
OR+Smart Peering
MDR Bi-Connected
Conclusions• The performance of OR has been enhanced with
use of Unsynchronized Adjacencies.– Overhead compared to Bi-Connected MDR is
consistently lower.
• The higher-mobility characteristics tested are based on input provided by our customers.
• The Design Team should open the results and solicit input from the community in the interest of obtaining data on real-life deployment scenarios to base its final recommendation on.