Edge Device Multi-unicasting for Video StreamingTal Lavian Ph.D.
Multicast data stream from a server to multiple clients at the application level.
Overlay network structure must be constructed at the application layer to connect participating end systems
Mechanisms for adapting the overlay structure are necessary to provide and maintain adequate level of QoS of the application
Yoid – generic structure for overaly networks for content distribution
Overcast – single-source multicast
End System Multicast – small-scale multicast for teleconference
ALMI – an ALM infrastructure for multi-sender multicast that scales to a large number of groups with small number of members
Edge devices form overlay structure
Edge devices can replicate and multi-unicast to multiple clients
Overcome bottleneck problem over access link
Edge Device Multi-unicasting for Video StreamingTal Lavian Ph.D.
Multicast data stream from a server to multiple clients at the application level.
Overlay network structure must be constructed at the application layer to connect participating end systems
Mechanisms for adapting the overlay structure are necessary to provide and maintain adequate level of QoS of the application
Yoid – generic structure for overaly networks for content distribution
Overcast – single-source multicast
End System Multicast – small-scale multicast for teleconference
ALMI – an ALM infrastructure for multi-sender multicast that scales to a large number of groups with small number of members
Edge devices form overlay structure
Edge devices can replicate and multi-unicast to multiple clients
Overcome bottleneck problem over access link
This presentation is great introduction to the dynamic host configuraton protocol "DHCP".
It also provides more protocol based details together with the comparison to BOOTP protocol.
Implementation of multicast communication in internet
Individual hosts are configured as members of different multicast groups
One particular user may a member of many multicast groups
For a one multicast can be few members/nodes
IP Multicast group is identified by Class D address (224.0.0.0 – 239.255.255.255)
Every IP datagram send to a multicast group is transferred to all members of group
This presentation is great introduction to the dynamic host configuraton protocol "DHCP".
It also provides more protocol based details together with the comparison to BOOTP protocol.
Implementation of multicast communication in internet
Individual hosts are configured as members of different multicast groups
One particular user may a member of many multicast groups
For a one multicast can be few members/nodes
IP Multicast group is identified by Class D address (224.0.0.0 – 239.255.255.255)
Every IP datagram send to a multicast group is transferred to all members of group
Lecture 6 The Communication System Finalterm Slides
Chap 15 multicasting
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Objectives
Upon completion you will be able to:
• Differentiate between a unicast, multicast, and broadcast message
• Know the many applications of multicasting
• Understand multicast link state routing and MOSPF
• Understand multicast link state routing and DVMRP
• Understand the Core-Based Tree Protocol
• Understand the Protocol Independent Multicast Protocols
• Understand the MBONE concept
TCP/IP Protocol Suite 1
2. 15.1 UNICAST, MULTICAST,
AND BROADCAST
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TCP/IP Protocol Suite 2
8. NNoottee::
Emulation of multicasting through
multiple unicasting is not efficient and
may create long delays, particularly
with a large group.
TCP/IP Protocol Suite 8
10. 15.3 MULTICAST ROUTING
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TCP/IP Protocol Suite 10
11. NNoottee::
In unicast routing, each router in the
domain has a table that defines a
shortest path tree to possible
destinations.
TCP/IP Protocol Suite 11
17. NNoottee::
In the group-shared tree approach,
only the core router, which has a
shortest path tree for each group, is
involved in multicasting.
TCP/IP Protocol Suite 17
27. NNoottee::
RPB creates a shortest path broadcast
tree from the source to each destination.
It guarantees that each destination
receives one and only one
copy of the packet.
TCP/IP Protocol Suite 27
29. NNoottee::
RPM adds pruning and grafting to
RPB to create a multicast shortest path
tree that supports dynamic
membership changes.
TCP/IP Protocol Suite 29
30. 15.6 CBT
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TCP/IP Protocol Suite 30
32. Figure 15.13 Sending a multicast packet to the rendezvous router
TCP/IP Protocol Suite 32
33. NNoottee::
In CBT, the source sends the multicast
packet (encapsulated in a unicast packet)
to the core router.
The core router decapsulates the packet
and forwards it to all interested
interfaces.
TCP/IP Protocol Suite 33
35. NNoottee::
PIM-DM is used in a dense multicast
environment, such as a LAN.
TCP/IP Protocol Suite 35
36. NNoottee::
PIM-DM uses RPF and
pruning/grafting strategies to handle
multicasting.
However, it is independent from the
underlying unicast protocol.
TCP/IP Protocol Suite 36
37. NNoottee::
PIM-SM is used in a sparse multicast
environment such as a WAN.
TCP/IP Protocol Suite 37
38. NNoottee::
PIM-SM is similar to CBT but uses a
simpler procedure.
TCP/IP Protocol Suite 38
39. 15.8 MBONE
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TCP/IP Protocol Suite 39
